Brown algae obtain their brown color from the pigments fucoxanthin and chlorophyll a and c. Brown pigments absorb blue-green light, allowing brown algae to photosynthesize at depth where green light has been filtered out. Red algae contain additional red and blue pigments called phycocyanin and phycoerythrin which also help them absorb blue-green light for photosynthesis at depth. Kelps are an example of a large, complex brown alga that can reach 12 meters in length and form underwater forests. Red algae examples include the flat, sheet-like Porphyra laver and the slippery Aeodes orbits.
The document provides information about plants from the Devonian period. It discusses early vascular plants like Rhynia, Cooksonia, and Aglaophyton that were found in the Rhynie Chert fossil site in Scotland. These included the earliest known plants with specialized tissues for transport of water and nutrients. The document also describes the diversification of early plant groups like the Zosterophylls and Trimerophytes that occurred during the Devonian period and were ancestral to modern plant divisions.
1. The document discusses the evolution and classification of early vascular land plants, known from fossil evidence. It describes important plant groups from the Ordovician to Devonian periods, including Cooksonia, Rhynia, Aglaophyton, Zosterophyllum, trimerophytes, lycophytes, equisetales, and progymnosperms.
2. Many of these early plants were found preserved as fossils in sites like Rhynie, Scotland, which provide important insights into the origin and diversification of vascular plants.
3. By the late Devonian and Carboniferous periods, lycophytes had diversified and some groups included large trees, while ferns and hor
Rhyniophyta were early vascular plants that lived during the Devonian period. They lacked leaves, seeds, and flowers, instead having simple shoots that branched from a creeping axis and sometimes ended in spore capsules. Rhynia was a single-species genus from this group that had a creeping stem and upright aerial shoots bearing oval sporangia. Cooksonia was an early genus from the Rhyniophyta discovered in Wales, dating back to around 400 million years ago in the late Silurian period.
This document summarizes information about the early vascular plants Rhynia and Asteroxylon. It describes the classification of Rhynia in the division Pteridophyta, order Psilophytales, family Rhyniaceae, and genus Rhynia. Details are provided on the two Rhynia species, their morphology, growth habit, and sporangia. The classification and features of Asteroxylon are also outlined, noting it had branching stems up to 12 mm in diameter that arose from leafless rhizomes. References used in the document are listed at the end.
Bryophyte are intermediate between thallophyta and pteridophyta. They are known as plant amphibians and include mosses, liverworts, and hornworts. Bryophytes reproduce via spores and have a life cycle with both a gametophyte and sporophyte phase in alternation of generations. They can be found growing in a wide range of habitats.
This document discusses the classification and economic importance of bryophytes. It classifies bryophytes into three classes: Hepaticopsida (liverworts), Anthocerotopsida (hornworts), and Bryopsida (mosses). It describes key characteristics of each class. Bryophytes have economic importance as they help prevent soil erosion, aid in soil formation, can retain large amounts of water, and peat made from sphagnum is used as fuel and manure. Bryophytes also serve as a food source for animals in some areas and some species have medicinal uses or are used as indicator plants.
This document summarizes the characteristics of Protolepidodendron, a group of small herbaceous plants from the Devonian and Mississippian periods that were related to later giant lycophytes. Some key features included their forked leaves, which distinguished them from other lycophytes. Specimens grew up to half a meter tall. They had aerial and underground stems covered in small bifurcated leaves. The stems contained a triangular protostele, and some leaves bore sporangia. Protolepidodendron represents the earliest lycophytes to have ligules. They were widespread before going extinct in the mid-Carboniferous period.
The document provides information about plants from the Devonian period. It discusses early vascular plants like Rhynia, Cooksonia, and Aglaophyton that were found in the Rhynie Chert fossil site in Scotland. These included the earliest known plants with specialized tissues for transport of water and nutrients. The document also describes the diversification of early plant groups like the Zosterophylls and Trimerophytes that occurred during the Devonian period and were ancestral to modern plant divisions.
1. The document discusses the evolution and classification of early vascular land plants, known from fossil evidence. It describes important plant groups from the Ordovician to Devonian periods, including Cooksonia, Rhynia, Aglaophyton, Zosterophyllum, trimerophytes, lycophytes, equisetales, and progymnosperms.
2. Many of these early plants were found preserved as fossils in sites like Rhynie, Scotland, which provide important insights into the origin and diversification of vascular plants.
3. By the late Devonian and Carboniferous periods, lycophytes had diversified and some groups included large trees, while ferns and hor
Rhyniophyta were early vascular plants that lived during the Devonian period. They lacked leaves, seeds, and flowers, instead having simple shoots that branched from a creeping axis and sometimes ended in spore capsules. Rhynia was a single-species genus from this group that had a creeping stem and upright aerial shoots bearing oval sporangia. Cooksonia was an early genus from the Rhyniophyta discovered in Wales, dating back to around 400 million years ago in the late Silurian period.
This document summarizes information about the early vascular plants Rhynia and Asteroxylon. It describes the classification of Rhynia in the division Pteridophyta, order Psilophytales, family Rhyniaceae, and genus Rhynia. Details are provided on the two Rhynia species, their morphology, growth habit, and sporangia. The classification and features of Asteroxylon are also outlined, noting it had branching stems up to 12 mm in diameter that arose from leafless rhizomes. References used in the document are listed at the end.
Bryophyte are intermediate between thallophyta and pteridophyta. They are known as plant amphibians and include mosses, liverworts, and hornworts. Bryophytes reproduce via spores and have a life cycle with both a gametophyte and sporophyte phase in alternation of generations. They can be found growing in a wide range of habitats.
This document discusses the classification and economic importance of bryophytes. It classifies bryophytes into three classes: Hepaticopsida (liverworts), Anthocerotopsida (hornworts), and Bryopsida (mosses). It describes key characteristics of each class. Bryophytes have economic importance as they help prevent soil erosion, aid in soil formation, can retain large amounts of water, and peat made from sphagnum is used as fuel and manure. Bryophytes also serve as a food source for animals in some areas and some species have medicinal uses or are used as indicator plants.
This document summarizes the characteristics of Protolepidodendron, a group of small herbaceous plants from the Devonian and Mississippian periods that were related to later giant lycophytes. Some key features included their forked leaves, which distinguished them from other lycophytes. Specimens grew up to half a meter tall. They had aerial and underground stems covered in small bifurcated leaves. The stems contained a triangular protostele, and some leaves bore sporangia. Protolepidodendron represents the earliest lycophytes to have ligules. They were widespread before going extinct in the mid-Carboniferous period.
Lichens are a symbiotic organism consisting of algae or cyanobacteria in association with fungi. They can grow in extreme environments where the individual partners could not survive alone. There are over 15,000 known lichen species worldwide. Lichens are classified based on the type of fungi present and can take crustose, foliose, fruticose, or squamulose forms. They reproduce asexually via spores or sexually through fusion of algal and fungal cells. Lichens play an important ecological role in building soil and are a food source for animals, with some species also having commercial uses.
D I V E R S I T Y I N L I V I N G O R G A N I S M S ( I I T E R M )Nandeesh Laxetty
The document provides an overview of the classification of living organisms, including plants and animals. It discusses the main kingdoms of plants (Thallophyta, Bryophyta, Pteridophyta, etc.) and their characteristics. It also outlines the animal kingdom from simplest to most complex, discussing key phyla such as Porifera, Coelenterata, Platyhelminthes, etc. It concludes with describing the characteristics of main classes of vertebrates like Reptilia, Aves, Mammalia.
This document provides an overview of the course "Phycology" which is the study of algae. It discusses key topics that will be covered in the course including:
- Definitions of important terms like phycology, algae, and their characteristics.
- The different types of algal ecology such as planktonic, benthic, thermal, soil, symbiotic, etc. algae and examples of each.
- The various algal thallus organizations including unicellular, colonial, filamentous, and parenchymatous forms.
- Methods of algal reproduction including vegetative reproduction through fragmentation or budding, and sexual and asexual reproduction involving spores or game
This document provides an introduction and overview of marine plankton diatoms found along the west coast of North America. It begins with a general discussion that describes the key characteristics and structure of diatoms, including their cell walls known as frustules which consist of overlapping valves and connecting bands. The document then discusses diatom biology, physiology, importance as a food source, and methods for collecting and examining them under microscopes. It aims to provide identification of common species found in plankton samples from the region.
This was my powerpoint presentation when asked to present the habitat and occurrence of algae. I put pictures of the different algae per habitat including the species and genus,
This document discusses botanical nomenclature and the rules for naming plants. It begins by explaining that botanical nomenclature is the process of naming plants according to international rules proposed by botanists. It then discusses the history of plant naming including the development of the binomial system by Linnaeus and establishment of Latin as the language for plant names. The document concludes by outlining some of the key principles and rules of the International Code of Botanical Nomenclature including requirements for valid publication of new plant names.
Towards a Natural Classification of Diatoms (Bacillariophyceae)EukRef
This document discusses efforts to develop a natural classification system for diatoms that is supported by DNA evidence and reflects their evolutionary relationships. It provides background on diatoms, including their diversity and unique silica cell structure. Previous classification systems grouped diatoms into non-evolutionary relationships, but new analyses using DNA data aim to establish monophyletic groups that accurately capture diatom phylogeny. The document proposes a new higher-level classification of diatoms into consistently resolved, DNA-supported clades.
This document provides information about diatoms and dinoflagellates. It discusses their cell structure, reproduction, motility, and other key characteristics. The main points are:
- Diatoms and dinoflagellates are unicellular algae found in aquatic habitats. Diatoms have a silica cell wall called a frustule, while dinoflagellates have a complex cell covering called an amphiesma.
- Both reproduce through vegetative reproduction or sexual reproduction involving gametes. Some forms can also produce resting cells or spores.
- Motility in diatoms is through gliding, while dinoflagellates move using two flagella.
- Their chloroplast
1. Diatoms are single-celled algae with cell walls made of silica. They come in many shapes and sizes and are found in both freshwater and marine environments.
2. Their cell walls are made of two parts called theca that fit together like a box and lid. Locomotion is achieved through the secretion of mucus from structures called raphe.
3. Diatoms are classified based on their cell symmetry and wall ornamentation. They are divided into two main orders - centric diatoms which are radially symmetrical and pennate diatoms which are bilaterally symmetrical.
The document provides an overview of plant evolution and diversity. It begins with the earliest aquatic algae and charophytes, transitions to the first land plants like Cooksonia, and traces the major lineages including bryophytes, lycophytes, ferns, gymnosperms like cycads and conifers, and finally flowering plants. Key adaptations that facilitated the colonization of land are discussed. Various terms related to plant reproduction and life cycles are also defined.
Bryophytes likely represent three separate evolutionary lineages known as mosses, liverworts, and hornworts. Each moss sporophyte consists of a foot, stalk, and capsule that extends from the gametophyte plant and is somewhat parasitic, though able to produce some of its own food. Mosses are estimated to include between 10,000 to 15,000 species classified into four major groups: Sphagnopsida, Andreaeopsida, Polytrichopsida, and Bryopsida. Higher-level moss classification remains unresolved.
This document provides an overview of binomial nomenclature, which is the system used to universally name plant species. It discusses how binomial nomenclature was introduced by Linnaeus in 1751 to address issues with common names varying between locations and sometimes referring to different species. The document then explains how binomial nomenclature works, using two names (genus and species epithet), and the advantages it provides. It also outlines the International Code of Nomenclature which standardizes botanical naming, and how this code has evolved over time through different botanical congresses to establish standardized rules.
The document discusses the evolution of plants from non-vascular to vascular forms, and their eventual colonization of land. It focuses on the division of vascular plants into seedless and seeded forms. Seed plants like gymnosperms and angiosperms were able to spread widely on land due to the adaptation of pollen, which allowed for fertilization without needing water. Gymnosperms are divided into four groups including conifers, and have male and female cones that produce gametophytes involved in wind pollination.
- Lycophytes were some of the earliest land plants and include club mosses, spike mosses, and quillworts. They produce spores through sporophylls, which are modified leaves containing sporangia. Most lycophytes are homosporous, producing one type of spore.
- Seedless vascular plants evolved to have two types of vascular tissue - xylem and phloem. Xylem transports water and minerals through dead tracheid cells, while phloem transports sugars and other organic compounds through living cells. Roots evolved from subterranean stems to anchor plants and absorb water and nutrients from the soil. Leaves evolved from stem outgrowths to increase
Lichen is a symbiotic organism consisting of a fungus and an alga or cyanobacteria. The document defines lichen and describes its history, structure, forms, reproduction, habitat, economic importance. Lichens can be crustose, foliose, or fruticose depending on their thallus structure. They reproduce sexually through structures like apothecia and asexually through fragmentation or spores. Lichens grow in various habitats and have importance as food, medicine, dyes, and for their role in nitrogen fixation.
This document provides an overview of the classification of gymnosperms by different researchers over time. It discusses the key characteristics of modern gymnosperms and describes the four orders that living gymnosperms are commonly grouped into: Cycadales, Ginkgoales, Coniferales, and Gnetales. For each order, it highlights some representative genera and provides details on morphological features. The classification schemes of various scientists who studied gymnosperms, such as Bentham and Hooker, Engler, Coulter and Chamberlain, are summarized. Diagrams of their classification systems are also included.
Pteridophytes were the first vascular plants to evolve, originating around 400 million years ago. They are characterized by having well-developed vascular tissue for transporting water and nutrients. Pteridophytes reproduce via spores and have alternation of generations, with both gametophyte and sporophyte generations. They differ from other plants in being non-flowering and non-seed producing. Common examples include ferns, clubmosses, and horsetails. Pteridophytes first dominated terrestrial ecosystems but now many species thrive in moist, shaded environments.
This document provides an overview of taxonomy and biological classification. It discusses how Carolus Linnaeus established the scientific system of naming and ranking organisms in hierarchical groups. The key levels are domain, kingdom, phylum, class, order, family, genus and species. It then describes the major taxonomic groups across the three domains of life - Archaea, Bacteria and Eukarya. Within each kingdom, it outlines the characteristic phyla, classes, orders and other subgroups. The document concludes with a brief discussion of proposed alternatives to Linnaeus' classification system, such as the PhyloCode.
The document discusses several types of gymnosperms from the fossil record, including Lyginopteris, Williamsonia, Glossopteris, and Pentoxylon. It provides details on their morphological features, reproductive structures, and fossil evidence. Key points include:
- Lyginopteris was a vine-like plant with large fronds that reproduced via Crossotheca male structures and ovules covered by cupules.
- Williamsonia was a tall, palm-like plant that bore spirally arranged ovules on a conical receptacle for female reproduction and bifid microsporophylls bearing synangia for male reproduction.
- Glossopteris had simple, reticulate-veined leaves and reproduced
Presentation about the red algae .
Includes the introduction and some brief knowledge about some red algae like thalus
Reproduction and its importance.
This document discusses seaweeds and plants found in marine environments. It describes seaweeds as multicellular algae that come in three main types - green, brown, and red. The document outlines the key characteristics of seaweeds like their thallus structure and lack of true roots, stems, and leaves. It also discusses economic uses of seaweeds and their role as primary producers. Finally, it briefly introduces flowering seagrasses, salt-marsh plants, and mangroves as examples of marine-adapted angiosperms.
Lichens are a symbiotic organism consisting of algae or cyanobacteria in association with fungi. They can grow in extreme environments where the individual partners could not survive alone. There are over 15,000 known lichen species worldwide. Lichens are classified based on the type of fungi present and can take crustose, foliose, fruticose, or squamulose forms. They reproduce asexually via spores or sexually through fusion of algal and fungal cells. Lichens play an important ecological role in building soil and are a food source for animals, with some species also having commercial uses.
D I V E R S I T Y I N L I V I N G O R G A N I S M S ( I I T E R M )Nandeesh Laxetty
The document provides an overview of the classification of living organisms, including plants and animals. It discusses the main kingdoms of plants (Thallophyta, Bryophyta, Pteridophyta, etc.) and their characteristics. It also outlines the animal kingdom from simplest to most complex, discussing key phyla such as Porifera, Coelenterata, Platyhelminthes, etc. It concludes with describing the characteristics of main classes of vertebrates like Reptilia, Aves, Mammalia.
This document provides an overview of the course "Phycology" which is the study of algae. It discusses key topics that will be covered in the course including:
- Definitions of important terms like phycology, algae, and their characteristics.
- The different types of algal ecology such as planktonic, benthic, thermal, soil, symbiotic, etc. algae and examples of each.
- The various algal thallus organizations including unicellular, colonial, filamentous, and parenchymatous forms.
- Methods of algal reproduction including vegetative reproduction through fragmentation or budding, and sexual and asexual reproduction involving spores or game
This document provides an introduction and overview of marine plankton diatoms found along the west coast of North America. It begins with a general discussion that describes the key characteristics and structure of diatoms, including their cell walls known as frustules which consist of overlapping valves and connecting bands. The document then discusses diatom biology, physiology, importance as a food source, and methods for collecting and examining them under microscopes. It aims to provide identification of common species found in plankton samples from the region.
This was my powerpoint presentation when asked to present the habitat and occurrence of algae. I put pictures of the different algae per habitat including the species and genus,
This document discusses botanical nomenclature and the rules for naming plants. It begins by explaining that botanical nomenclature is the process of naming plants according to international rules proposed by botanists. It then discusses the history of plant naming including the development of the binomial system by Linnaeus and establishment of Latin as the language for plant names. The document concludes by outlining some of the key principles and rules of the International Code of Botanical Nomenclature including requirements for valid publication of new plant names.
Towards a Natural Classification of Diatoms (Bacillariophyceae)EukRef
This document discusses efforts to develop a natural classification system for diatoms that is supported by DNA evidence and reflects their evolutionary relationships. It provides background on diatoms, including their diversity and unique silica cell structure. Previous classification systems grouped diatoms into non-evolutionary relationships, but new analyses using DNA data aim to establish monophyletic groups that accurately capture diatom phylogeny. The document proposes a new higher-level classification of diatoms into consistently resolved, DNA-supported clades.
This document provides information about diatoms and dinoflagellates. It discusses their cell structure, reproduction, motility, and other key characteristics. The main points are:
- Diatoms and dinoflagellates are unicellular algae found in aquatic habitats. Diatoms have a silica cell wall called a frustule, while dinoflagellates have a complex cell covering called an amphiesma.
- Both reproduce through vegetative reproduction or sexual reproduction involving gametes. Some forms can also produce resting cells or spores.
- Motility in diatoms is through gliding, while dinoflagellates move using two flagella.
- Their chloroplast
1. Diatoms are single-celled algae with cell walls made of silica. They come in many shapes and sizes and are found in both freshwater and marine environments.
2. Their cell walls are made of two parts called theca that fit together like a box and lid. Locomotion is achieved through the secretion of mucus from structures called raphe.
3. Diatoms are classified based on their cell symmetry and wall ornamentation. They are divided into two main orders - centric diatoms which are radially symmetrical and pennate diatoms which are bilaterally symmetrical.
The document provides an overview of plant evolution and diversity. It begins with the earliest aquatic algae and charophytes, transitions to the first land plants like Cooksonia, and traces the major lineages including bryophytes, lycophytes, ferns, gymnosperms like cycads and conifers, and finally flowering plants. Key adaptations that facilitated the colonization of land are discussed. Various terms related to plant reproduction and life cycles are also defined.
Bryophytes likely represent three separate evolutionary lineages known as mosses, liverworts, and hornworts. Each moss sporophyte consists of a foot, stalk, and capsule that extends from the gametophyte plant and is somewhat parasitic, though able to produce some of its own food. Mosses are estimated to include between 10,000 to 15,000 species classified into four major groups: Sphagnopsida, Andreaeopsida, Polytrichopsida, and Bryopsida. Higher-level moss classification remains unresolved.
This document provides an overview of binomial nomenclature, which is the system used to universally name plant species. It discusses how binomial nomenclature was introduced by Linnaeus in 1751 to address issues with common names varying between locations and sometimes referring to different species. The document then explains how binomial nomenclature works, using two names (genus and species epithet), and the advantages it provides. It also outlines the International Code of Nomenclature which standardizes botanical naming, and how this code has evolved over time through different botanical congresses to establish standardized rules.
The document discusses the evolution of plants from non-vascular to vascular forms, and their eventual colonization of land. It focuses on the division of vascular plants into seedless and seeded forms. Seed plants like gymnosperms and angiosperms were able to spread widely on land due to the adaptation of pollen, which allowed for fertilization without needing water. Gymnosperms are divided into four groups including conifers, and have male and female cones that produce gametophytes involved in wind pollination.
- Lycophytes were some of the earliest land plants and include club mosses, spike mosses, and quillworts. They produce spores through sporophylls, which are modified leaves containing sporangia. Most lycophytes are homosporous, producing one type of spore.
- Seedless vascular plants evolved to have two types of vascular tissue - xylem and phloem. Xylem transports water and minerals through dead tracheid cells, while phloem transports sugars and other organic compounds through living cells. Roots evolved from subterranean stems to anchor plants and absorb water and nutrients from the soil. Leaves evolved from stem outgrowths to increase
Lichen is a symbiotic organism consisting of a fungus and an alga or cyanobacteria. The document defines lichen and describes its history, structure, forms, reproduction, habitat, economic importance. Lichens can be crustose, foliose, or fruticose depending on their thallus structure. They reproduce sexually through structures like apothecia and asexually through fragmentation or spores. Lichens grow in various habitats and have importance as food, medicine, dyes, and for their role in nitrogen fixation.
This document provides an overview of the classification of gymnosperms by different researchers over time. It discusses the key characteristics of modern gymnosperms and describes the four orders that living gymnosperms are commonly grouped into: Cycadales, Ginkgoales, Coniferales, and Gnetales. For each order, it highlights some representative genera and provides details on morphological features. The classification schemes of various scientists who studied gymnosperms, such as Bentham and Hooker, Engler, Coulter and Chamberlain, are summarized. Diagrams of their classification systems are also included.
Pteridophytes were the first vascular plants to evolve, originating around 400 million years ago. They are characterized by having well-developed vascular tissue for transporting water and nutrients. Pteridophytes reproduce via spores and have alternation of generations, with both gametophyte and sporophyte generations. They differ from other plants in being non-flowering and non-seed producing. Common examples include ferns, clubmosses, and horsetails. Pteridophytes first dominated terrestrial ecosystems but now many species thrive in moist, shaded environments.
This document provides an overview of taxonomy and biological classification. It discusses how Carolus Linnaeus established the scientific system of naming and ranking organisms in hierarchical groups. The key levels are domain, kingdom, phylum, class, order, family, genus and species. It then describes the major taxonomic groups across the three domains of life - Archaea, Bacteria and Eukarya. Within each kingdom, it outlines the characteristic phyla, classes, orders and other subgroups. The document concludes with a brief discussion of proposed alternatives to Linnaeus' classification system, such as the PhyloCode.
The document discusses several types of gymnosperms from the fossil record, including Lyginopteris, Williamsonia, Glossopteris, and Pentoxylon. It provides details on their morphological features, reproductive structures, and fossil evidence. Key points include:
- Lyginopteris was a vine-like plant with large fronds that reproduced via Crossotheca male structures and ovules covered by cupules.
- Williamsonia was a tall, palm-like plant that bore spirally arranged ovules on a conical receptacle for female reproduction and bifid microsporophylls bearing synangia for male reproduction.
- Glossopteris had simple, reticulate-veined leaves and reproduced
Presentation about the red algae .
Includes the introduction and some brief knowledge about some red algae like thalus
Reproduction and its importance.
This document discusses seaweeds and plants found in marine environments. It describes seaweeds as multicellular algae that come in three main types - green, brown, and red. The document outlines the key characteristics of seaweeds like their thallus structure and lack of true roots, stems, and leaves. It also discusses economic uses of seaweeds and their role as primary producers. Finally, it briefly introduces flowering seagrasses, salt-marsh plants, and mangroves as examples of marine-adapted angiosperms.
This document discusses seaweeds and plants found in marine environments. It describes seaweeds as multicellular algae that come in three main types - green, brown, and red. The document outlines the key characteristics of seaweeds like their thallus structure and lack of true roots, stems, and leaves. It also discusses economic uses of seaweeds and their role as primary producers. Finally, it briefly introduces flowering seagrasses, salt-marsh plants, and mangroves as examples of marine-adapted angiosperms.
Mangroves are trees and shrubs that grow in coastal saline habitats in the tropics and subtropics. They produce leaf litter that decomposes into detritus, providing a food source for marine life. Mangroves have adaptations like pneumatophores and salt glands that allow them to survive in salty, low-oxygen soil. Their seeds and propagules can disperse long distances in water. Mangrove ecosystems support a diverse array of wildlife like birds, snakes, turtles and more.
This document provides an introduction to algae, including their definition, characteristics, structure, classification, and examples of different types. Algae are a diverse group of photosynthetic organisms that can range in size from microscopic to large seaweeds. They are classified into multiple kingdoms, with most falling under Protista or Monera. Major divisions of algae include green algae, red algae, brown algae, diatoms, and cyanobacteria. The document concludes by listing examples of algae commonly observed under the microscope.
This document provides information on various classification systems used in taxonomy and discusses different divisions of algae. It begins by explaining phylogenetic, numerical, cytotaxonomy, and chemotaxonomy classification systems. It then describes key characteristics of different algal divisions - Chlorophyceae, Phaeophyceae, and Rhodophyceae. The document also summarizes reproduction in algae and provides examples of economically important algae.
Algae as primary producers, economic imp, toxic blooms.pdfSamuelJohn684299
Algae play important roles in several industries and aspects of human life. They are used as fertilizers in agriculture due to their ability to fix nitrogen in soil. Some algae like Spirogyra and Oedogonium are used as human food. Algae also serve as food sources for fish, making them important for aquaculture. Several algal products like agar, carrageenan, and algin are used in food, pharmaceutical, and other industries. Algae indicators can identify industrial waste pollutants. However, some algae are toxic or cause harmful algal blooms that pollute water sources.
Harmful algal blooms (HABs) are overgrowths of algae that can produce toxins or otherwise be harmful to people, animals, and ecosystems. They occur in freshwater, brackish, and marine environments. Factors that contribute to HABs include increased salinity, carbon dioxide, nutrients from eutrophication, temperature, and coastal upwelling. Blooms are caused by various algal species and can have red, green, or brown discoloration. Toxins produced can harm humans and wildlife. Mitigation methods include physical removal, chemicals, and biological controls but each has limitations for large-scale application.
Algae are a diverse group of photosynthetic organisms that can exist as single-celled or multicellular forms. They are found in a variety of habitats from oceans to freshwater and even snow. Algae play important roles in ecosystems and have many uses including producing oxygen, forming the base of the aquatic food chain, and providing products for food, medicine, and biofuels.
This document discusses the biology of algae. It defines algae as a diverse group of photosynthetic, eukaryotic organisms that exist in various aquatic and damp environments. Algae range from unicellular to multicellular forms and can be found in many colors, including red, green, and blue, depending on their pigments. While similar to plants in that they conduct photosynthesis, algae lack true roots, stems, leaves and vascular tissues. They reproduce both sexually and asexually and play an important role in food chains and carbon dioxide fixation. The document also provides examples of different algae types and their various economic uses.
Plant Biodiversity classifications life cycles.pptxSehrishSarfraz2
The document discusses plant biodiversity and classification. It covers several kingdoms of plants including algae, bryophyta, pteridophyta, and gymnosperms. For each kingdom, it describes key characteristics such as plant structure, life cycles, and examples of types of plants. It also discusses economic importance for some kingdoms.
Intro to algae aaabbbcccdddjwnjdjdjjdjhhhHajiAdeel1
This document provides an introduction to algae, including their definition, characteristics, structure, where they live, classification, and examples of different types. Algae are a diverse group of photosynthetic organisms that can be unicellular or multicellular. They are classified into divisions based on their pigments, storage products, cell wall composition, and genetic differences. Major divisions of algae include cyanobacteria, euglenophyta, chlorophyta, chrysophyta, bacillariophyta, phaeophyta, and rhodophyta. Examples are provided for different algal types such as Chlamydomonas for chlorophyta and Fucus for phaeophyta.
This document provides information on various types of aquatic and marine plants. It begins by discussing the importance of water on Earth and the role of algae in producing oxygen and sequestering carbon. It then describes the divisions of algae and provides examples of species from each division. The document outlines the life cycles and reproductive strategies of different types of algae. It also discusses seaweeds, their uses, and the author's research on seaweeds. Finally, it briefly covers other aquatic plants like seagrasses, mangroves, freshwater algae, lichens, bryophytes, ferns, and invasive species.
Seagrasses thrive in shallow, saline, and brackish waters worldwide, from tropical zones to the Arctic Circle. Resembling grass but botanically related to terrestrial flowering plants, seagrasses have roots, stems, leaves, and the ability to produce flowers and seeds, with an evolutionary history dating back around 100 million years. Despite their unassuming appearance, seagrasses play a crucial role as one of the planet's most productive ecosystems.
Seaweed cultivation of sargassum is introduced. Seaweed are marine algae that live in marine or brackish water and contain photosynthetic pigments to produce food through photosynthesis using sunlight and nutrients. Sargassum is a genus of brown algae in the order Fucales that is commonly found in coastal waters. It has a thallus body with structures like a lamina, stipe, and holdfast and provides food and shelter for other organisms.
The document discusses the marine ecosystem and its various components. It describes the pelagic and benthic divisions of the marine environment. The pelagic division includes the neritic and oceanic zones, while the benthic division encompasses the littoral and deep-sea systems. It also discusses the five major kingdoms found in the ocean - Monera, Protista, Fungi, Metaphyta and Metazoa. Additionally, it examines the key components of the marine ecosystem including plankton organisms, zooplankton, nekton community, benthos organisms, coral reefs and mangrove swamps. Finally, it outlines some problems facing marine ecosystems such as natural and
The document provides information on seaweeds or macroalgae. It discusses their taxonomy, structure, ecology, common genera and uses. Seaweeds are a source of food, hydrocolloids like agar and carrageenan used in food production, and have applications in medicine, fertilizer, and other industrial uses. The Philippines cultivates various seaweed species like Eucheuma and Kappaphycus which are sources of carrageenan, an emulsifier used in food and other industries. Seaweed farming involves selecting a suitable pollution-free site and using culture methods like stakes, suspended ropes, or raft and spider web systems to grow the seaweeds.
Transgenic animals are created using two main methods: DNA microinjection and manipulating embryonic stem cells. Examples of transgenic animals include GH-mice with increased growth, marathon mice with enhanced endurance, and goats producing the human blood clotting protein Antithrombin in their milk. Transgenic fish like GloFish have been genetically engineered to fluoresce for environmental monitoring. Mammalian cloning is done through nuclear transfer as demonstrated by Dolly the sheep. Transgenic technologies allow for applications like disease modeling and industrial production of human therapeutic proteins from the milk of livestock.
Brown algae obtain their brown color from the pigments fucoxanthin and chlorophyll a and c. Brown pigments absorb blue-green light, allowing brown algae to photosynthesize at depth where green light has been filtered out. Red algae contain red and blue pigments in addition to chlorophyll a, allowing them to also photosynthesize in deep water. Common South African brown algae include kelps, wracks, sargassums, and dictyotas. Red algae are more diverse and include large flat sheets, delicate branches, and succulent forms. Both brown and red algae play important ecological roles and have various commercial uses.
Prokaryotic and eukaryotic cells differ in their processes of transcription. Prokaryotes lack a nucleus and nucleolus, and their DNA is located in the cytoplasm. Transcription and translation occur simultaneously in prokaryotes. Eukaryotic cells have membrane-bound nuclei containing DNA, and transcription occurs separately from translation within the nucleus.
1. Vaucheria is a yellow-green, filamentous, aquatic or terrestrial alga that grows in dense tufts.
2. It reproduces asexually through the production of multiflagellate zoospores inside club-shaped sporangia or non-motile aplanospores.
3. Under unfavorable conditions, it produces thick-walled akinetes or hypnospores that can directly form new plants when conditions improve.
This document discusses the classification system of flowering plants developed by George Bentham and Joseph Dalton Hooker in the 19th century. It was one of the first comprehensive natural systems, grouping 202 orders (now families) of angiosperms based on their morphological and reproductive characteristics. Some of the major divisions in their system included monocotyledons, dicotyledons divided into polypetalae and gamopetalae based on their floral parts. Within polypetalae and gamopetalae were further subgroups like thalami florae, disci florae and calyci florae. The system had advantages of being natural and easy to follow but also drawbacks like placement of gymnosperms and neglect
Diiagnosiis of UTI Quiick Refference Guiide ffor Priimary CareDr. Aurora Bakaj
This document provides guidance on diagnosing and managing urinary tract infections (UTIs). It recommends not routinely culturing urine or treating asymptomatic bacteriuria in elderly patients or patients with catheters. For adult women under 65 with urinary symptoms but no vaginal issues, empirical antibiotic treatment can be given without culturing urine. Culturing is recommended for pregnant women, suspected pyelonephritis, failed antibiotic treatment, or recurrent UTIs. Escherichia coli with extended-spectrum beta-lactamases are increasing, and are usually sensitive to nitrofurantoin or fosfomycin.
CNIO Frontiers Meeting New Trends in Anticancer Drug Development March 22‐25,...Dr. Aurora Bakaj
This document provides an agenda for the CNIO Frontiers Meeting on New Trends in Anticancer Drug Development taking place from March 22-25, 2015 at the Spanish National Cancer Research Centre in Madrid. Over the three day program, there will be keynote lectures and talks on new targets and pathways in clinical development for cancer treatment, innovative drug development approaches including clinical trial design and biomarkers, immunotherapy, and personalized cancer medicine. Speakers will discuss topics such as androgen receptor blockade, PI3K/mTOR inhibitors, DNA damage repair pathways, antibody-drug conjugates, targeting the epigenome, cancer metabolism, applications of cancer genomics, and integrating patient-derived tumor xenograft models.
This study examined the incidence of asymptomatic bacteriuria and pyuria in 86 pregnant women and 56 non-pregnant women in Iran. Bacteriological and microscopic urine analysis found that 29.1% of pregnant women had asymptomatic bacteriuria compared to 5.4% of non-pregnant women, and 20.9% of pregnant women had pyuria compared to 5.4% of non-pregnant women. The most common bacteria found in pregnant women was Staphylococcus epidermidis (36%). The study concludes that the incidence of asymptomatic bacteriuria is significantly higher in pregnant women, especially in the first trimester, compared to non-pregnant women. Urine culture is necessary for screening
This document defines and describes the five main groups of vertebrate animals: mammals, birds, reptiles, fish, and amphibians. It provides details about the key characteristics of each group, such as mammals having hair and giving live birth, birds having feathers and laying eggs, reptiles having scales and laying eggs, fish living in water and breathing through gills, and amphibians being able to live on land and in water. The document aims to teach students about the different types of vertebrate animals and their defining biological traits.
Occult blood, urobilinogen, WBC-esterase, and nitrite are substances that may be present in urine and can indicate infections if found. Normal urine is a shade of yellow and clear, while abnormal appearances like cloudy, milky, red, or orange urine may suggest issues like infections or other medical conditions. Understanding urinalysis results involves considering factors like a person's physical characteristics, medical history, medications, and lifestyle habits.
Microbial characterisation and identification, and potability of River Kuywa ...Open Access Research Paper
Water contamination is one of the major causes of water borne diseases worldwide. In Kenya, approximately 43% of people lack access to potable water due to human contamination. River Kuywa water is currently experiencing contamination due to human activities. Its water is widely used for domestic, agricultural, industrial and recreational purposes. This study aimed at characterizing bacteria and fungi in river Kuywa water. Water samples were randomly collected from four sites of the river: site A (Matisi), site B (Ngwelo), site C (Nzoia water pump) and site D (Chalicha), during the dry season (January-March 2018) and wet season (April-July 2018) and were transported to Maseno University Microbiology and plant pathology laboratory for analysis. The characterization and identification of bacteria and fungi were carried out using standard microbiological techniques. Nine bacterial genera and three fungi were identified from Kuywa river water. Clostridium spp., Staphylococcus spp., Enterobacter spp., Streptococcus spp., E. coli, Klebsiella spp., Shigella spp., Proteus spp. and Salmonella spp. Fungi were Fusarium oxysporum, Aspergillus flavus complex and Penicillium species. Wet season recorded highest bacterial and fungal counts (6.61-7.66 and 3.83-6.75cfu/ml) respectively. The results indicated that the river Kuywa water is polluted and therefore unsafe for human consumption before treatment. It is therefore recommended that the communities to ensure that they boil water especially for drinking.
Improving the viability of probiotics by encapsulation methods for developmen...Open Access Research Paper
The popularity of functional foods among scientists and common people has been increasing day by day. Awareness and modernization make the consumer think better regarding food and nutrition. Now a day’s individual knows very well about the relation between food consumption and disease prevalence. Humans have a diversity of microbes in the gut that together form the gut microflora. Probiotics are the health-promoting live microbial cells improve host health through gut and brain connection and fighting against harmful bacteria. Bifidobacterium and Lactobacillus are the two bacterial genera which are considered to be probiotic. These good bacteria are facing challenges of viability. There are so many factors such as sensitivity to heat, pH, acidity, osmotic effect, mechanical shear, chemical components, freezing and storage time as well which affects the viability of probiotics in the dairy food matrix as well as in the gut. Multiple efforts have been done in the past and ongoing in present for these beneficial microbial population stability until their destination in the gut. One of a useful technique known as microencapsulation makes the probiotic effective in the diversified conditions and maintain these microbe’s community to the optimum level for achieving targeted benefits. Dairy products are found to be an ideal vehicle for probiotic incorporation. It has been seen that the encapsulated microbial cells show higher viability than the free cells in different processing and storage conditions as well as against bile salts in the gut. They make the food functional when incorporated, without affecting the product sensory characteristics.
Evolving Lifecycles with High Resolution Site Characterization (HRSC) and 3-D...Joshua Orris
The incorporation of a 3DCSM and completion of HRSC provided a tool for enhanced, data-driven, decisions to support a change in remediation closure strategies. Currently, an approved pilot study has been obtained to shut-down the remediation systems (ISCO, P&T) and conduct a hydraulic study under non-pumping conditions. A separate micro-biological bench scale treatability study was competed that yielded positive results for an emerging innovative technology. As a result, a field pilot study has commenced with results expected in nine-twelve months. With the results of the hydraulic study, field pilot studies and an updated risk assessment leading site monitoring optimization cost lifecycle savings upwards of $15MM towards an alternatively evolved best available technology remediation closure strategy.
Presented by The Global Peatlands Assessment: Mapping, Policy, and Action at GLF Peatlands 2024 - The Global Peatlands Assessment: Mapping, Policy, and Action
Optimizing Post Remediation Groundwater Performance with Enhanced Microbiolog...Joshua Orris
Results of geophysics and pneumatic injection pilot tests during 2003 – 2007 yielded significant positive results for injection delivery design and contaminant mass treatment, resulting in permanent shut-down of an existing groundwater Pump & Treat system.
Accessible source areas were subsequently removed (2011) by soil excavation and treated with the placement of Emulsified Vegetable Oil EVO and zero-valent iron ZVI to accelerate treatment of impacted groundwater in overburden and weathered fractured bedrock. Post pilot test and post remediation groundwater monitoring has included analyses of CVOCs, organic fatty acids, dissolved gases and QuantArray® -Chlor to quantify key microorganisms (e.g., Dehalococcoides, Dehalobacter, etc.) and functional genes (e.g., vinyl chloride reductase, methane monooxygenase, etc.) to assess potential for reductive dechlorination and aerobic cometabolism of CVOCs.
In 2022, the first commercial application of MetaArray™ was performed at the site. MetaArray™ utilizes statistical analysis, such as principal component analysis and multivariate analysis to provide evidence that reductive dechlorination is active or even that it is slowing. This creates actionable data allowing users to save money by making important site management decisions earlier.
The results of the MetaArray™ analysis’ support vector machine (SVM) identified groundwater monitoring wells with a 80% confidence that were characterized as either Limited for Reductive Decholorination or had a High Reductive Reduction Dechlorination potential. The results of MetaArray™ will be used to further optimize the site’s post remediation monitoring program for monitored natural attenuation.
Climate Change All over the World .pptxsairaanwer024
Climate change refers to significant and lasting changes in the average weather patterns over periods ranging from decades to millions of years. It encompasses both global warming driven by human emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. While climate change is a natural phenomenon, human activities, particularly since the Industrial Revolution, have accelerated its pace and intensity
ENVIRONMENT~ Renewable Energy Sources and their future prospects.tiwarimanvi3129
This presentation is for us to know that how our Environment need Attention for protection of our natural resources which are depleted day by day that's why we need to take time and shift our attention to renewable energy sources instead of non-renewable sources which are better and Eco-friendly for our environment. these renewable energy sources are so helpful for our planet and for every living organism which depends on environment.
1. The importance of brown pigments
Brown algae are generally khaki-brown in colour, due to the
possession of green pigments (chlorophyll a and c) and the
brown fucoxanthin. The different pigments absorb different
coloured light and this is very important for seaweeds that live
in deeper water. Sunlight contains all the colours of the rainbow
mixed to form ‘white light’. Green objects reflect the green
light but absorb the other colours particularly violet and red.
As light passes through water it is filtered out so that it
becomes darker the deeper one goes. But red and violet light
disappear first and blue-green light penetrates furthest, giving
deep water its characteristic blue hue. Unfortunately this means
that green seaweeds with only green pigments are not able to
absorb this blue-green light at depths. Brown pigments can
absorb the blue-green light energy and pass it to the green
chlorophyll for photosynthesis (a process whereby algae
manufacture food from carbon dioxide and water using light
energy). A unique starch, laminarin is produced in brown algae.
EXAMPLES OF BROWN SEAWEEDS
Kelps Three common species of kelp occur on the west
coast, the sea bamboo, Ecklonia maxima, the split fan kelp,
Laminaria pallida, and the bladder kelp, Macrocystis angustifolia.
A smaller kelp, Ecklonia biruncinata, with spiny blades is found
on the south coast. Most of the kelps have growth points in
the middle of the plant, usually where the blades join the stipe.
This is an advantage because the blade can continue to grow
at its base while the tip is worn and grazed away. Kelps have
the most complex tissues of all algae, the stipes (stems) have
strengthening tissues and tubular cells to transport the food
through the plant. The blades are many cells thick with a
protective outer layer, pigmented photosynthetic cells and
storage tissues containing starch and tannin, to deter herbi-
vores. Spores are produced in specialised sporangia situated in
raised patches (sori) on the blades. During its life cycle the kelp
alternates between the huge spore producing plant (sporophyte)
and microscopic male and female plants (gametophytes) that
produce the gametes. The gametophytes contain half the
number of chromosomes (n) that the sporophytes have (2n).
he brown algae include some of the largest
and most complex seaweeds: the kelps, wracks
and sargassums. Brown algae belong to the Phylum
Phaeophyta and are particularly common in the
temperate zones of the world, although many species
of sargassum grow in warmer waters. One sargassum
forms enormous floating rafts in the doldrums near
the equator and has given its name to the Sargasso
Sea. Kelps can reach a length of 12 m and form
extensive forests along the west coast of South Africa,
creating a unique ecosystem where animals and
plants live and feed in the calm shelter of the kelp
‘trees’. On the subtropical east coast of South Africa
the brown seaweeds are generally small and some of
them are vivid yellow or blue in colour. Most brown
algae secrete chemicals that deter herbivores; these
may be tannins, lime or even sulphuric acid, found
in the acid weed, Desmarestia firma.
T
Brown Algae
C O A S TA L A N D M A R I N E L I F E : P R O T O C T I S T A : A L G A E
3G
Life-cycle of the Split fan kelp
zoospores (n)
zygote (n)
sperm
fertilization(2n)
sporophyte (2n)
(about 4 m)
spore-producing
sorus
female gametopnyte
(n) (about 1 mm)
male gametopnyte (n)
(about 1 mm)
egg
Dead man’s fingers Acid weed Turban weed
blade
growth point
stipe
holdfast
2. During fertilisation the male and female gametes fuse and
grow into a new large kelp sporophyte.
Sargassum and Turbinaria The sargassums are bushy
seaweeds with stems and leaf-like blades. Some of them
use bladders to hold them up to the light. Special repro-
ductive branches occur in the axils of the blades.
Several different species occur in South Africa, in deep
gullies and intertidal pools. In tropical areas the related
Turban weed, Turbinaria ornata, is found in which
compact bushes bear trumpet-shaped fertile branches.
Wracks Carpets of hanging wracks, Bifurcaria
brassicaeformis, clothe wave pounded rocks between
Saldanha Bay and Cape Agulhas. The tough
cylindrical axes hang from creeping holdfasts.
Spear-shaped reproductive blades bear
gametes in cavities along their margins.
The tiny eggs hang from the branches on
mucous threads so that they are not
washed out of the surf zone where they
live. The wracks are related to the common European
seaweed Fucus. Splachnidium rugosum, commonly
called deadman’s fingers occurs on rocky shores.
When underwater, the finger-like bladders of
mucous are swollen but as the tide drops, they
lose water from the bladders and become
wrinkled and withered, although their living
skin is not damaged.
Dictyota group (Flat forking branches) There are
many thin, flat brown seaweeds, Dictyota species,
that grow from an apical cell that divides, forming
regular forked (dichotomous) branching.
Dictyopteris species are similar but the blades
have a central midrib.
Zonaria group (Fan-shaped) Fan-shaped brown
seaweeds grow from a meristem along the rim of the fan.
They are especially common on the east coast, where
delicate light brown Turkeytails, Padina boryana, cluster in
shallow mid-tide pools, and the large, more flexible Zonaria
and Stypopodium species occur low on the shore.
Cushion-shaped Colpomenia sinuosa usually grows
epiphytically on other algae. Its yellowish, hollow balls often
fill with oxygen and float and can become a nuisance in
oyster farms because they lift the
oysters and float them away – hence
their name ‘oyster thief’.
Uses
Brown seaweeds have been used over the centuries
as fertilizers. Apart from their nutrient value they are
natural fungicides and retain water, forming an
excellent mulch. Brown seaweeds are rich in
iodine and at one time were burnt to
extract potash. This activity had disas-
trous results in Ireland, as the seaweeds were no
longer used to mulch the potato crops and a
devastating potato blight destroyed the harvest
and led to famine. Kelp tablets are used to treat goitre
and skin complaints. In South Africa kelps are com-
mercially important. They are harvested fresh and
liquidised under pressure to be used as a growth
stimulant to dramatically increase the yield of crops
such as wheat and tomatoes. Washed-up kelps are
collected and dried for the extraction of alginic acid,
a gel widely used as stabilisers and emulsifiers in
ice-cream, toothpaste, cosmetics and thousands
of other products. Alginic acid fixes radioactive
strontium allowing it to be removed from the body.
Insoluble alginate salts are used to waterproof tiles
and seal fine paper. A sludge of kelp, containing
seeds can be sprayed on soil embankments
to prevent erosion. Dried kelp is exported and
not processed in South Africa.
Author: Margo Branch September 2000
FURTHER INFORMATION: • Botany Department, University of the Western Cape, Cape Town. Tel. (021) 959 3201.
• Branch, G. M. & Branch M. L. 1981. The Living Shores of Southern Africa. Struik, Cape Town.
• Branch, G. M., Griffiths, C. L., Branch M. L & Beckley, L. E. 1994. Two Oceans: A guide to the marine life of southern Africa, David Philip, Claremont, Cape Town.
• Stegenga, H., Bolton, J. & Anderson, R. 1994. Seaweeds of the South African West Coast. Contrib. Bolus Herbarium.
• Seaweed Research Unit, University of Cape Town, Rondebosch, Cape. Tel.(021) 650 3717.
RELATED FACTSHEETS: • Kelp Forests • Seaweeds and their Uses • Plankton • Green Algae • Red Algae • Classification of Marine Species
For more information, please contact: The Coastal Management Office, Marine and Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2,
Roggebaai 8012, Cape Town, South Africa. Tel: +27 (0)21 402-3208 Fax: +27 (0)21 418-2582 e-mail: czm@mcm.wcape.gov.za Website: http://sacoast.wcape.gov.za
Classification:
KINGDOM: Protoctista
PHYLUM: Phaeophyta: Brown Algae
Turkeytail
Oyster
thief
Hanging
wrack
Dictyota
3. The red algae are seaweeds belonging to the Phylum
Rhodophyta that are distinguished from other seaweeds by
the presence of unique red and blue pigments, phycocyanin
and phycoerythrin, in addition to green chlorophyll a. The red
and blue pigments are a great advantage to these sea-
weeds as they can absorb blue-green light in deep water,
passing the energy to chlorophyll for food production
by photosynthesis. Red algae can live both high
on the shore and at great depths. Deep-
water plants have more red pigments,
while those in the intertidal may be red-
dish brown, yellowish or almost black. As
a result many red algae are confused with
brown algae (Phylum Phaeophyta) that are yel-
low-brown in colour. One species of intertidal red
alga, Hypnea spicifera, is often taken to be a green
alga as it appears bright green and only the
lower parts of the plant are pink. It has potential
commercial importance for the extraction of carrageenan.
Generally, the red algae are very palatable and provide the
staple diet for many of the marine herbivores, such as
molluscs, crustaceans and fish. The food reserve is floridean
starch, which is different from the starch stored in higher
plants and other seaweeds. Red algae are also a source
of agar, a gelling substance, of economic importance in
confectionery and as a growth medium for bacteriological
studies. A few such as the pink coralline algae are impregnated
with lime and deter herbivores.
There are many different species of red algae with a diverse
range of plant forms and a variety of complex life cycles.
They are more common on the west and south coasts as
they thrive in the rich waters where upwelling brings nutrients
to the surface to be mixed by the turbulent water.
here are hundreds of species of red algae
along the coast of South Africa. Some are
large flat, blood-red sheets, others are delicately
branched, but the majority are succulent, red-
brown plants that populate the fringe of the ocean.
T
Red Algae
C O A S TA L A N D M A R I N E L I F E : P R O T O C T I S T A : A L G A E
3G
Hypnea
spicifera
Hedgehog weedSlippery orbitsPurple laver
4. Adapted to the conditions
The seaweeds are adapted to cope with the physical stresses
they encounter where they live. Those living high on the shore
are able to withstand severe desicca-
tion during low tide and are often large
and flat to be able to absorb the maxi-
mum nutrients and sunlight for photo-
synthesis during the short period that
they are submerged. Mid- and low-
shore species have to contend with
wave action as well as desiccation.
Many of them are branched or covered
with papillae to increase their surface
area without providing too much resist-
ance to the waves. The agar in their
bodies, enables them to retain water
and reduce drying out. In deep water where there is a short-
age of light and reduced wave action, the sea-
weeds tend to be large, flat and red.
Many red seaweeds grow epiphyti-
cally on other algae especially kelps
and, like the ferns and creepers in a
forest, are held up to the sunlight.
They are delicately branched so they
flow with the water as the kelps sway in
the waves.
EXAMPLES OF COMMON RED
SEAWEEDS
High shore, intertidal, flat
red seaweeds
on the west coast
Purple laver, Porphyra capensis, is a
fast-growing, membranous seaweed that
looks like crumpled black plastic when dried.
As the tide rises the fronds expand and soft-
en as they absorb water into the mucilagi-
nous layer between the cells. The female
plants have pink edges and the males yellow
edges, from which the gametes are released.
Porphyra is confined to the very high shore because
grazers eliminate it lower on the shore. Porphyra
species are eaten by humans in the Far East
and made into laver bread with oatmeal in
Wales. They are tasty when added to soups, stews
or savory biscuits.
Slippery orbits, Aeodes orbitosa, forms
extremely slippery, yellowish-brown, tough sheets, attached
to mid-shore rocks by a thickened disc. It is seldom eaten
by grazers.
Spotted iridea, Iridea capensis, forms brown
strap-shaped blades with dark spots when fertile. Unlike
Aeodes it has a rough texture and is not slippery.
Hedgehog seaweed, Notogenia stiriata, is very dark black-
ish-brown and occurs on sheltered rocks. It is papery when dry
and the two phases of the life cycle differ. The gametophyte
phase is covered with small, branched outgrowths while the
tetrasporophyte is usually fairly smooth with a few papil-
lae along the margin. If held to the light the
dark spots can be seen indicating the
pockets of four spores (tetraspores).
FURTHER INFORMATION: • Botany Department, University of the Western Cape, Cape Town. Tel. (021) 959 3201.
• Branch, G. M. & Branch M. L. 1981. The Living Shores of Southern Africa . Struik, Cape Town.
• Branch, G. M., Griffiths, C. L., Branch M. L & Beckley, L. E. 1994. Two Oceans: A guide to the marine life of southern Africa, David Philip, Claremont, Cape Town.
• Stegenga, H., Bolton, J. & Anderson, R. 1994. Seaweeds of the South African West Coast. Contrib. Bolus Herbarium.
• Seaweed Research Unit, University of Cape Town, Rondebosch, Cape. Tel.(021) 650 3717
RELATED FACTSHEETS: • Kelp Forests • Seaweeds and their Uses • Plankton • Green Algae • Brown Algae
For more information, please contact: The Coastal Management Office, Marine and Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2,
Roggebaai 8012, Cape Town, South Africa. Tel: +27 (0)21 402-3208 Fax: +27 (0)21 418-2582 e-mail: czm@mcm.wcape.gov.za Website: http://sacoast.wcape.gov.za
Classification:
KINGDOM: Protoctista
PHYLUM: Rhodophyta: Red Algae
Twisted
gigartina
Plocamium
Jointed coralline
Broad
wine-weed
Red
ribbons
5. Seaweeds have a simple structure
The seaweeds are simpler than land plants. Being emersed in
water, they can simply absorb nutrients, water, dissolved
gasses and sunlight through the entire surface of the plant.
They have no need for roots, leaves and a complex network
to transport food and water around the plant, as land plants
do. Some seaweeds such as the caulerpas have root-like
holdfasts, but these serve only to anchor the seaweeds on
the rocks or in the sand. The green seaweeds are particularly
simple in structure and have three basic body plans. Some
like the sea lettuce form thin sheets only one or two cells
thick. In others such as the hairweeds the cells are placed
end to end in a single row. A third group (the Siphonales)
which includes the caulerpas and the codiums are made up
of a network of fine tubes.
Life cycles of green algae
Most seaweeds have at least two different generations that
alternate during the life cycle. An asexual spore-producing
generation (the sporophyte) produces many spores, which
settle and grow into male and female gametophytes. The
gametophytes produce gametes. During fertilization the male
and female gametes fuse and the resulting zygote develops
into a new sporophyte generation. The gametophyte genera-
tions have half the number of chromosomes (genetic material)
found in the sporophyte generation. The gametophyte is said
to be haploid (n) while the sporophyte is termed diploid (2n).
During the cell division leading to the production of spores
(meiosis) these paired chromosomes are parted with half
going to one spore and the other half to another. In the sea
lettuce, Ulva, the sporophytes and the gametophytes look
alike but in many seaweeds the two generations are different.
EXAMPLES OF GREEN SEAWEEDS
A) Flat sheets one or two cells thick (Order Ulotricales)
Sea lettuces (Ulva and Monostroma species) and Intestine
weeds (Enteromorpha species) are common in intertidal pools
and estuaries. They are quick to colonise any bare areas on
he green algae are common inhabitants of
both salt and fresh water. Green algae belong
to the Phylum Chlorophyta and are thought to be
the ancestors of land plants. Like land plants they
are green in colour due to the presence of the pig -
ments chlorophyll a and b. Both algae and land
plants can manufacture their own food by a process
called photosynthesis. This involves using the
chlorophyll to absorb the light energy from the sun
and converting carbon dioxide and water into simple
sugars and oxygen. By this process the light energy
is converted to chemical energy and stored as
calories in food. The sugars can be combined with
nitrogen and other mineral salts to make proteins
and other organic compounds. All animals are
either directly or indirectly dependent on algae and
plants for food and their energy for life. Seaweeds
are the algae found on the shallow fringes of the
ocean where the sunlight can penetrate.
T
Green Algae
C O A S TA L A N D M A R I N E L I F E : P R O T O C T I S T A : A L G A E
3G
Sea lettuce Hair weed Codium
6. rocks. They are able to tolerate a wide range salinities that
may be caused when rain or rivers dilute the sea or, alter-
nately, when heat causes evaporation and an increase in
salinity. The spores are formed along the edges of the fronds
and are released on the rising tide, when cool water enters
pools. The spores are dispersed by the waves to colonise
new areas. Sea lettuces are widely eaten in the Far East.
They are cultivated on rafts off the coast of East and West
Africa and are a potential future source of food and income
for South Africa.
B) Filaments of cells end to end (Order Cladophorales)
The simple unbranched hair weeds (Chaetomorpha species)
and the branched Cladophora species grow like tufts of grass
on the side of pools or attached to larger seaweeds. Like hair,
they flow with the movement of the waves and are not easily
broken. Their spores are released from the tips of the hairs.
C) Complex green seaweeds (Order Siphonales)
The more complex green seaweeds are made up of fine
branching tubes with numerous nuclei and few or no cross-
walls. The green chloroplasts move within these tubes to
make the most of light conditions. They may retreat from the
surface to avoid excess light or move to exposed tips when a
plant is smothered by sand. Many of them
contain chemicals that act as deterrents
to herbivores. There are more species
along the east coast than the west coast
of South Africa. The codiums are thick,
spongy dark-green seaweeds, some
of the species are upright and branching
while others form cushions of overlapping lobes
or balls. There are many different species of
Caulerpa, particularly in tropical and
subtropical waters, in which tan-
gled root-like rhizomes give
rise to upright blades. These
may
be strap-like, feathery or
covered with bunches of green
‘berries’. The strap
caulerpa forms dense stands in
sandy gullies where they can survive being partially smothered
by sand.
Three other easily identified, green seaweeds are found on
the east coast; the wedge weed, Halemeda cuneata, with its
series of flattened calcified green discs, green fans, Udotea
orientalis and the black-green bubbles of Valonia macrophysa.
There are many green algae living in rivers and fresh-water
ponds. Author: Margo Branch September 2000
FURTHER INFORMATION: • Botany Department, University of the Western Cape, Cape Town. Tel. (021) 959 3201.
• Branch, G. M. & Branch M. L. 1981. The Living Shores of Southern Africa. Struik, Cape Town.
• Branch, G. M., Griffiths, C. L., Branch M. L & Beckley, L. E. 1994. Two Oceans: A guide to the marine life of southern Africa, David Philip, Claremont, Cape Town.
• Stegenga, H., Bolton, J. & Anderson, R. 1994. Seaweeds of the South African West Coast. Contrib. Bolus Herbarium.
• Seaweed Research Unit, University of Cape Town, Rondebosch, Cape. Tel.(021) 650 3717.
RELATED FACTSHEETS: • Kelp Forests • Seaweeds and their Uses • Plankton • Brown Algae • Red Algae
For more information, please contact: The Coastal Management Office, Marine and Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2,
Roggebaai 8012, Cape Town, South Africa. Tel: +27 (0)21 402-3208 Fax: +27 (0)21 418-2582 e-mail: czm@mcm.wcape.gov.za Website: http://sacoast.wcape.gov.za
Green balloons Wedge weed Strap caulerpa
Classification:
KINGDOM: Protoctista
PHYLUM: Chlorophyta: Green Algae