The document provides an overview of algae, defining them as aquatic, eukaryotic, photosynthetic organisms that can be unicellular or multicellular, lacking true roots, stems, or leaves. It discusses their ecological importance, reproductive methods, diverse types, and their role in the food chain, contributing significantly to oxygen production and environmental health. Additionally, advances in technology have enabled the production of algal biofuels, offering a sustainable alternative to traditional fossil fuels.

1. Algae
The term "algae" refers to a class of mostly watery, photosynthetic, and nucleus-
bearing organisms that lack the real roots, stalks, and leaves of plants as well as their
specialized multicellular reproductive systems.
What are Algae?
In addition to ponds, brackish waterways, and even snow, seaweed may be found in rivers,
lakes, seas, and ponds. seaweed are often green, although they can also be found in other
hues. For instance, the carotenoid pigments and chlorophyll present in the seaweed that
live in snow give the surrounding snow its unique red color.
Continue reading to learn more about the many kinds and traits of algal cells from the
notes provided below.

2. Seaweed Definition
"The name "alga" refers to a huge and extraordinarily diversified class of eukaryotic,
photosynthetic lifeforms. These species are not linked to one another (polyphyletic) since
they do not have a common ancestor.
Giant kelp and brown algae are two examples of multicellular algae. Examples of
unicellular organisms include dinoflagellates, euglenophytes, and diatoms.
Since most algae need a moist or wet environment to thrive, they can be found
everywhere near or inside water bodies. They have anatomical similarities with the
land plants, a significant group of photosynthetic creatures. The distinctions stop there
since seaweed lack many of the structural elements that are generally seen in plants,
such as real stems, shoots, and leaves. Additionally, they lack the vascular tissues
needed to transport vital nutrients and water throughout their bodies.

3. Characteristics of Seaweed
Plants and animals share specific general properties of seaweed.
Eukaryotic cells make up seaweed. Algae, for example, may photosynthesize like
plants and have specialized cell organelles like centrioles and flagella that are
exclusively found in animals. Manna's, cellulose, and Galatians make up the algal cell
walls. Some of the general characteristics of algae are listed below.
 Seaweed are photosynthetic organisms
 Seaweed can be either unicellular or multicellular organisms
 Seaweed lack a well-defined body, so, structures like roots, stems or leaves
are absent
 seaweed are found where there is adequate moisture.
 Reproduction in algae occurs in both asexual and sexual forms. Asexual
reproduction occurs by spore formation.
 Seaweed are free-living, although some can form a symbiotic relationship with
other organisms.
Types of Saweed
Algae come in a variety of varieties. But these are a few of the more well-known
kinds:
Red Scum
It is a peculiar species that is also known as Rhodophyta, and it may be found in both
freshwater and marine settings. The distinctive red hue of the algae is caused by the
pigments phycocyanin and phycoerythrin. There are other pigments that give things
their green hue, such chlorophyll a. But neither beta-carotene nor chlorophyll B are
present.

4. Green Algae
It is a large, loosely organized collection of scum that include the essential pigments
for photosynthetic activity, chlorophylls A and B, as well as auxiliary pigments like
xanthophyll's and beta carotene.
Green scum carry out photosynthesis for higher creatures. Symbiotic relationships
exist between different types of green algae and other living things.
Members include flagellates, colonies, flagella, and unicellular organisms. Spirogyra,
Ulothrix, Volvox, and other well-known species of green algae are examples.
Reading Further: Chloroplasts
Not an Algae: Blue-Green Algae

5. One of the most well-known forms of SC cumin the past was blue-green scum.
However, because all square categorized as eukaryotic organisms, blue-green algae
are not currently included under the category of algae because they are prokaryotes.
These creatures, often known as cyanobacteria, thrive in damp or watery conditions
exactly like other algae. Dams, rivers, reservoirs, streams, lakes, and seas are some of
them. This group of bacteria uses photosynthesis to produce energy. Some types of
blue-green algae are important to the environment ecologically because they fix
nitrogen in the soil. They are also known as nitrogen-fixing bacteria because of this.
Anabaena, Nostos, etc.
Read more about Rhizobium, the bacteria that fixes nitrogen.
Other varieties of blue-green algae, however, can be poisonous to people. They may
either be neurotoxic (have negative
Examples of Algae
 Prominent examples of algae include:
 Ulothrix
 Focus
 Porphyria
 Spirogyra
Algal Biofuel
Algal fuel can now be produced because to recent advances in science and
technology. The employment of environmentally acceptable alternatives like algae
biofuel has been encouraged by worsening environmental health and a global need for
petroleum-based products. As a result, algal fuel is becoming a more and more
feasible substitute for conventional fossil fuels. Everything from "green" jet fuel to
"green" diesel is produced using it. It is comparable to other corn- and sugarcane-
based biofuels.
Explore BYJU'S Biology to learn more about algae, its varieties and properties, or any
other biological ideas.
Further Reading:
 Lichens
 Thallophyte
 Difference Between Algae And Fungi
 Vaucheria: Classification, structure and Life cycle

6.  Chlamydomonas: Classification, Structure and Life Cycle
Frequently Asked Questions
1. What are Scum?
A sizable and varied class of eukaryotic, photosynthetic organisms that are not
necessarily linked to one another is known as scum.
2. How are algae different from traditional plants?
Algae are not genuine plants since they lack actual roots, stalks, and leaves. As a
result, they require proximity to a wet or watery environment to thrive. In other
words, they lack the vascular tissue required for the transport of minerals and water.
3. Briefly outline the types of algae.
 square primarily classified into the following types:
 Blue-green scum
 Red scum
 Green scum
4. State the general characteristics of algae.
 scumare either unicellular or multicellular in nature
 Found in moist places
 Mode of reproduction can be sexual as well as asexual
 Asexual reproduction occurs by spore formation
 Sexual reproduction occurs by the physical contact of haploid gametes
 Lacks a well-defined body
 They are photosynthetic in nature
 Are mostly free-living
5. State 4 examples of algae.
 Volvox
 Spirogyra
 Ulothrix
 Focus
6. Are scum bacteria or a plant?

7. Neither bacteria nor plants are scum. A broad category of photosynthetic, eukaryotic
creatures is referred to as scum.
7. Are scum toxic to humans?
square often safe for people to consume. However, some types of scum can produce
algal blooms, which can be harmful to both the environment and human health.
8. How are algae useful?
A known 50% carbon dioxide fixation rate for algae. They raise the oxygen level in
their environment because they are photosynthetic. They are the main producers, and
other creatures depend on them for sustenance. Algae are used to make a variety of
commercial goods, including align, etc.
9. Why are algae important?
For many creatures in the food chain, algae serve as their principal food supply. Algae
grow quite quickly, which makes them highly helpful economically for producing
biomass or fertilizers.
Algae
Members of the kingdom Protista's group of mostly watery photosynthetic creatures
are known as scum, or alga. scum come in a wide variety of sizes and life cycles, from
tiny Micro monas species to enormous kelps that may grow to a length of 60 meters
(200 feet). Their cells have characteristics not found in either plants or animals, and
their photosynthetic pigments are more varied than those of plants. In addition to their
ecological functions as oxygen providers and the primary source of nutrition for
practically all aquatic life, algae play a significant economic role as a source of crude
oil, food, and a variety of medical and industrial goods for humans. Algal taxonomy is
contested and vulnerable to quick change when fresh molecular data is found.
Scum were first divided into broad groupings according to color starting in the 1830s,
such as red, brown, and green. Different chloroplast pigments, including chlorophylls,
carotenoids, and phycobiliproteins, are reflected in the colors. There are a lot more
than just three classes of pigments recognized, and each class of algae has its own
distinctive collection of pigment types.

8. The phylogeny of the group has not yet been determined, and the algae are not closely
linked to one another in terms of evolution. Without the existence of chloroplasts and
photosynthesis as distinguishing characteristics, several kinds of algae are difficult to
identify from protozoa and fungus. In fact, compared to other algae, certain algae
seem to share a closer evolutionary link with protozoa or fungus.
Physical and ecological features of algae
Size range and diversity of structure
There are seven orders of magnitude between the sizes of the algae. While the largest
algae have millions of cells, many algae only have one cell. Groups of cells in big,
macroscopic algae are specialized for certain tasks including anchoring, transport,
photosynthesis, and reproduction; this specialization denotes a certain level of
complexity and evolutionary progress.

9. Based on the morphology of their vegetative, or growing, condition, the algae may be
classified into a number of categories. Cells in filamentous forms are organized in
chains that resemble strings of pearls. While some filaments, like Spirogyra, are
unbranched, others, like Stigeoclonium, are branched and bushy in appearance.
Numerous adjacent filaments joined laterally give rise to the gross morphological
form of many red algae (such as Palmaris). Parenchymatous (tissue like) formations
can reach lengths of many meters, like the enormous kelp (Microcystic). Algae that
are coenocytic reach quite great sizes without producing discrete cells, as the green
seaweed Corium. In essence, coenocytic algae are multinucleated, unicellular algae
without cell walls dividing the protoplasm (the cytoplasm and nuclear components of
a cell). Some algae swim and have flagella.

10. Ecological and commercial importance
Using sunlight to generate energy, algae use the process of photosynthesis to create
organic food molecules from carbon dioxide and water. Algae, like land plants, are at
the bottom of the food chain, and since there aren't many plants in the ocean, algae are
ultimately responsible for the survival of almost all marine species, including whales,
seals, fish, turtles, shrimp, lobsters, clams, octopuses, sea stars, and worms. Algal
photosynthesis results in the production of oxygen in addition to organic compounds.
An estimated 30 to 50 percent of the net global oxygen required for human respiration
and that of other terrestrial animals is produced by algae.
Using sunlight to generate energy, algae use the process of photosynthesis to create
organic food molecules from carbon dioxide and water. Algae, like land plants, are at
the bottom of the food chain, and since there aren't many plants in the ocean, algae are
ultimately responsible for the survival of almost all marine species, including whales,
seals, fish, turtles, shrimp, lobsters, clams, octopuses, sea stars, and worms. Algal
photosynthesis results in the production of oxygen in addition to organic compounds.
An estimated 30 to 50 percent of the net global oxygen required for human respiration
and that of other terrestrial animals is produced by algae.
Using sunlight to generate energy, algae use the process of photosynthesis to create
organic food molecules from carbon dioxide and water. Algae, like land plants, are at
the bottom of the food chain, and since there aren't many plants in the ocean, algae are
ultimately responsible for the survival of almost all marine species, including whales,
seals, fish, turtles, shrimp, lobsters, clams, octopuses, sea stars, and worms. Algal
photosynthesis results in the production of oxygen in addition to organic compounds.
An estimated 30 to 50 percent of the net global oxygen required for human respiration
and that of other terrestrial animals is produced by algae.

11. During the 20th century, the diatoms (class Bacillariophyceae) were crucial to the
growth of industry. Diatom frustules, or cell walls, are composed of opaline silica and
have many small holes. Some sediments from lakes and oceans contain significant
amounts of frustules, and the fossilised byproduct of this deposition is known as
diatomite. About 3,000 diatom frustules per cubic millimetre (50 million frustules per
cubic inch) can be found in diatomite. Diatomite is easily mined when tectonic rising
raises diatomite deposits above sea level. For instance, a deposit in Lompoc,
California, U.S., is 13 square kilometres (5 square miles) in size and may reach a
depth of 425 metres (1,400 feet).
Diatomite has a high absorptive capacity, a sizable surface area, and a low bulk
density. It is also comparatively inert.
What are 4 benefits of algae?
During the 20th century, the diatoms (class Bacillariophyceae) were crucial to the
growth of industry. Diatom frustules, or cell walls, are composed of opaline silica and
have many small holes. Some sediments from lakes and oceans contain significant
amounts of frustules, and the fossilized byproduct of this deposition is known as
diatomite. About 3,000 diatom frustules per cubic millimeter (50 million frustules per
cubic inch) can be found in diatomite. Diatomite is easily mined when tectonic rising
raises diatomite deposits above sea level. For instance, a deposit in Lompoc,
California, U.S., is 13 square kilometer's (5 square miles) in size and may reach a
depth of 425 meters (1,400 feet).
Diatomite has a high absorptive capacity, a sizable surface area, and a low bulk
density. It is also comparatively inert.

12. What are 5 facts about algae?
 Algae is a one-celled plant that can grow in your pool if conditions are
favorable.
 There are over 400,000 known varieties of algae.
 Algae are mainly found in marine or freshwater environments.
 Algae produce oxygen which other aquatic life uses.
What are the 7 major types of algae?
 Euglenophyte (Eugenides)
 Cryophyte (Golden-brown algae and Diatoms)
 Pyrophyte (Fire algae)

13.  Chlorophyta (Green algae)
 Rhodophyta (Red algae)
 Paleophyte (Brown algae)
 Xanthophyte (Yellow-green algae
Terrestrial algae, snow algae, seaweeds, phytoplankton, and "pond scums" (which are
made up of stringy masses of cyanobacteria as well as genuine algae like Spirogyra)
are all included in the incredibly diverse group of creatures we refer to as "algae".
Algae are morphologically straightforward, chlorophyll-containing animals that may
be quite big and multicellular all the way up to tiny and unicellular (single-celled).
There are no true roots or leaves and the algal body is relatively unevolved. Algae are
generally autotrophic, meaning they obtain their energy (or "food") from their
environment, primarily from sunlight. They are crucial for sustaining the planet's
oxygen supply and food chains.
Algae are sometimes categorized as "plants" and other times as "protists" (a broad
classification of mostly unrelated creatures that are arranged according to
Some types of algae that may interest you
The immensely varied collection of organisms we refer to as "algae" includes
terrestrial algae, snow algae, seaweeds, phytoplankton, and "pond scums" (which are
made up of stringy masses of cyanobacteria as well as true algae like Spirogyra).
Chlorophyll-containing, morphologically simple, and ranging in size from fairly large
and multicellular to very small and unicellular (single-celled), are algae. The algal

14. body is quite primitive and lacks genuine roots or leaves. Algae are typically
autotrophic, which means they get their energy (or "food"), mostly from sunlight,
from their surroundings. They are essential for maintaining the planet's food chains
and oxygen supplies.
Algae are occasionally classified as "plants" and other times as "protists," a broad
category of largely unrelated animals that include
Phytoplankton: In freshwater and marine habitats, phytoplankton—drifting,
photosynthetic, primarily microscopic algae and cyanobacteria—form the base of
food webs by absorbing solar energy.
Blue-Green Algae: The creatures that are occasionally referred to as "blue-green
algae" are really a kind of bacteria currently referred to as cyanobacteria. They can,
however, superficially resemble real green algae since many of them are aquatic and
photosynthetic, occasionally forming noticeable colonies on the surface of stagnant
waters. In truth, there is a significant evolutionary link: the chloroplasts in the cells of
contemporary green plants (including green algae) were first discovered as
cyanobacteria living within other species, according to the now widely recognised
endosymbiotic explanation of organelle origins.
Where Scum Live Where can you find algae? Almost everywhere on Earth,
including corals, certain protozoans, and Cnidaria, as well as in the sea (down to 250
m in some locations), rivers, lakes, and ponds, on trees, soils, and walls, and as
symbiotic partners with fungus (as lichens). Almost anywhere there is light for
photosynthesis and where there is water for reproduction, there are algae. Scum , or
so-called extremophiles, are significant colonisers in hot springs and lava flows and
frequently thrive at extremely high temperatures. Algae-like organisms are among the
most likely to be discovered if life is present somewhere else in our solar system.

15. Reproduction in Scum

16. The majority of algae produce some type of spore, a reproductive cell that is
frequently motile (capable of movement) in algae. Scum frequently reproduce
asexually in a variety of ways, but they may also reproduce sexually through meiosis,
which produces genetically varied gametes that are subsequently fused together to
form new individuals. Some types of algae have very basic forms of sex in which the
Scum serve as the gametes, but many other types of algae have sperm- and egg-like
cells as well as pheromones that attract sex. It is believed that an alga was the first
creature to evolve sexual reproduction, which we now observe in plants and animals,
some 1.5 billion years ago.
General Characteristics of Algae
The most common unicellular algae are found in water, particularly in plankton. The
population of unicellular algae-dominated free-floating microorganisms is known as
phytoplankton. Additionally, moist soil, moist rocks, and moist wood can all support
the growth of algae. Lichens include both fungal and Scum .
The Whittaker method divides scum into seven divisions, five of which are thought to
belong to the Protista kingdom and two to the Plantae kingdom. Scum have eukaryotic
cells, and certain species have microtubule flagella with the "9 plus 2" pattern. In
mitosis, a nucleus is seen, and several chromosomes are seen. Chloroplasts, which
have membranes called thylakoids, are where the chlorophyll and other coolers are
found in living things.
The majority of scum do photosynthesis and are photoautotrophic.
Reference
 cience/algae#:~:text=What%20are%20algae%3F,multicellular%20reproductive%20structures%2
0of%20plants.

17.  https://microbiologysociety.org/why-microbiology-matters/what-is-microbiology/algae.html