Your SlideShare is downloading. ×
Unit 4 Notes
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Unit 4 Notes

972

Published on

Published in: Education
0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
972
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
0
Comments
0
Likes
1
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide
  • DiploidHaploidMeiosisZygoteEmbryoSpermGamete fusionGametophyte (n)n nnn SporesSpore mother cellSporangiaSporophyte (2n)2nSporeMitosisEgg2n2n
  • Transcript

    • 1. BIODIVERSITY
    • 2. Unit 4 – Organizing Biodiversity Unit 4 – Organizing Biodiversity Estimates of the number of species that inhabit our planet run as high as 10 million! That means 10 million different kinds of organisms. That number certainly suggests a lot of variety. That is what diversity means--variety. When we say "biodiversity," we refer to the variety of life.
    • 3. Biodiversity Previous Knowledge Assignment    
      • Make a list of as many different living organisms as you can think of.
      • After you have finished the list, cut out each name and place the organisms together into groups.
      • Give each group a name or brief title that says how they are alike.
      • Try to form additional groups so that you have groups within groups.
      • Again, name each group or provide a brief group heading that describes it.
      • On a fresh piece of paper redraw your classifications, using the group headings you have come up with.
      •  
      •  
      Unit 4 – Organizing Biodiversity
    • 4. Systematics  
      • Systematics is the branch of biology that deals with classifying living things, both current and prehistoric. There are two components:
      • Taxonomy & Classification – Taxonomy is the science of identifying and naming species and organizing them into a hierarchical systems of classification.
      • Phylogenetics – Determining the evolutionary history and relationships among the various forms of life through time. Relationships among organisms are expressed through diagrams known as cladograms.
      Unit 4 – Organizing Biodiversity
    • 5. Unit 4 – Organizing Biodiversity Taxonomic Hierarchy  
    • 6. Taxonomy  
      • Carolus Linnaeus (1707-1778) developed the hierarchical categorization system (kingdom, phylum, class, order, family, genus, species), and grouped organisms based on their resemblance to other life forms.
      Unit 4 – Organizing Biodiversity
    • 7. The Kingdoms Classification System
      • Below is a complete list of these categories:
      • Kingdom
      • Phylum
      • Class
      • Order
      • Family
      • Genus
      • Species
      Unit 4 – Organizing Biodiversity
    • 8. The Kingdoms Classification System
      • Each category has its own set of characteristics that organisms must have to fit into that group. If we compare organisms at the species level, they are all very much alike compared to each level moving up in the hierarchy.
      • At the kingdom level, there is great diversity but all members of a kingdom still share some similarities. As we move down the hierarchy, organisms share more and more common characteristics and show fewer differences.
      Unit 2 - Biodiversity
    • 9. The Kingdoms Classification System Unit 4 – Organizing Biodiversity
    • 10. Taxonomy  
      • Carolus Linnaeus also developed the binomial nomenclature system that is still in use today.
      • He assigned a two-word Latin name to each organism, with no two plant or animal species having the same name.
      • Today the genus and species levels of the classification system provide the specific name for each organism.
      • The genus and species designations are often referred to as the scientific names of organisms.
      Unit 4 – Organizing Biodiversity
    • 11. Taxonomy  
      • The genus name is always capitalized but the species name is not.
      • If typing, the genus and species name are always in italics.
      • If handwritten, the genus and species names are underlined.
      • When a number of species in the same genus are referenced, sometimes just the initial of the genus name is given with the species name.
      Unit 4 – Organizing Biodiversity
    • 12. Classification of Humans
      • Here is the complete classification of humans:
      • Kingdom - Animalia
      • Phylum - Chordata
      • Class - Mammalia
      • Order - Primates
      • Family - Hominidae
      • Genus - Homo
      • Species - Sapiens
      Unit 4 – Organizing Biodiversity
    • 13. Classification of Humans
      • Bionomial nomenclature is a system in which each species is assigned a two-word Latin name. Each species is distinguishable from each other. The first word designates the genus and the second word designates the species. Both words should be in italics.
      • Humans - Homo sapiens
      Unit 4 – Organizing Biodiversity
    • 14. Classification of Organisms
      • Your task is to provide complete classification for 2 different organisms.
      • You must write down the classification and include a picture of each.
      • Kingdom - __________
      • Phylum - __________
      • Class - __________
      • Order - __________
      • Family - __________
      • Genus - __________
      • Species - __________
      • Binomial nomenclature - _______ _______
      Unit 4 – Organizing Biodiversity
    • 15. Systematics  
      • Systematics is the branch of biology that deals with classifying living things, both current and prehistoric. There are two components:
      • Taxonomy & Classification – Taxonomy is the science of identifying and naming species and organizing them into a hierarchical systems of classification.
      • Phylogenetics – Determining the evolutionary history and relationships among the various forms of life through time. Relationships among organisms are expressed through diagrams known as cladograms.
      Unit 4 – Organizing Biodiversity
    • 16. Phylogenetic Trees  
      • A phylogenetic tree appears as a fan-like or tree-like diagram, with the base/trunk representing the origin of life and the blades/branches representing the various different groups of organisms. Ancestral species are located closest to the base/trunk, and present day species are located at the ends of the blades/branches.
      Unit 4 – Organizing Biodiversity
    • 17. Phylogenetic Trees   Unit 4 – Organizing Biodiversity
    • 18. Phylogenetic Trees   Unit 4 – Organizing Biodiversity
    • 19. Cladograms  
      • A cladogram is a visual reconstruction of the evolutionary history of a group of organisms. Cladograms appear as branching diagrams based on a sequenced pattern of ancestral (primitive) and derived (advanced) traits. Derived traits distinguish members of one evolutionary branch from another.
      Unit 4 – Organizing Biodiversity
    • 20. Cladograms   Unit 4 – Organizing Biodiversity
    • 21. Cladograms   Unit 4 – Organizing Biodiversity
    • 22. Cladograms   Unit 4 – Organizing Biodiversity
    • 23. Cladistics and Phylogeny
      • Cladistics
          • Clad-portion of a cladogram
            • Contains a common ancestor and all descendant species
            • All organisms in a clad exhibit the same characteristic
            • Arranged with the least amount of branching possible
      Unit 4 – Organizing Biodiversity
    • 24. Cladistics and Phylogeny
      • Traditionalists
        • Also consider descent from a common ancestor
          • But include consideration of amount of evolutionary change when grouping organisms
      Unit 4 – Organizing Biodiversity
    • 25. Evidence for the Classification of Organisms
      • Embryology
      • Morphology
      • Biochemistry
        • Protein Sequencing
      • DNA Analysis
        • DNA-DNA Hybridization
        • Comparing DNA Sequencing
      Unit 4 – Organizing Biodiversity
    • 26. Systematics  
      • The dynamic nature of classification is an excellent example of how the use of new and improved technologies led to changes in the entire system of classification.
        • Aristotle (384-322 BCE) created the first widely used classifications system by dividing all organisms into two groups; plants and animals.
        • Carolus Linnaeus (1707-1778) developed the hierarchical categorization system (kingdom, phylum, class, order, family, genus, species), and grouped organisms based on their resemblance to other life forms. The binomial nomenclature system developed by Linnaeus is still in use today.
      Unit 4 – Organizing Biodiversity
    • 27. Systematics  
        • Improvements in light microscopes led to the discovery of a great number of single-celled organisms. Ernst Haeckel suggested in 1866 that these organisms be placed in a separate kingdom called Protista.
        • The invention of the electron microscope and advances in biochemistry in the mid 1900’s led to the discovery of the two different types of cells; the prokaryotes (bacteria) and the eukaryotes (plants, animals, fungi, protists).
        • Robert Whittaker proposed the five kingdom system in 1959. Plants, animals, fungi, bacteria and protists were placed in separate kingdoms.
      Unit 4 – Organizing Biodiversity
    • 28. Systematics  
        • Analysis of the base sequence of ribosomal RNA in various bacteria by Carl Woese in the 1970’s led him to suggest that bacteria be subdivided two distinct groups, the eubacteria and archaebacteria.
        • Based on Woese’ s research, a six kingdom system was suggested. The plant, animal, fungi, and protist kingdoms remained, while the Kingdom Monera (bacteria) was separated into the Eubacteria and Archaebacteria kingdoms.
      Unit 4 – Organizing Biodiversity
    • 29. Systematics  
        • In 1990, Woese proposed the three domain scheme of classification consisting of Domain Eukaraya (all eukaryotes including animals, plants, fungi and protists), Domain Bacteria (“true” bacteria such as E. coli, Lactobacillus bulgaris, and Cyanobacteria ), and Domain Archaea (organisms that live in extreme environments such as high temperature or extreme salinity, or produce methane gas)
      Unit 4 – Organizing Biodiversity
    • 30. The Kingdoms Classification System Unit 4 – Organizing Biodiversity
    • 31. The Kingdoms Classification System
      • Below are the names of the five kingdoms
      • Kingdom Monera - bacteria and blue-green algae (prokaryotes)
      • Kingdom Protista - eukaryotic single-celled and multi-celled plant-like, animal-like, and fungal-like organisms
      • Kingdom Fungi - multicellular heterotrophic saprophytic organisms ( fungi)
      • Kingdom Plantae - multicellular photosynthetic organisms ( algae, mosses, ferns, and seed plants)
      • Kingdom Animalia - multicellular heterotrophic animals
      Unit 4 – Organizing Biodiversity
    • 32. Unit 4 – Organizing Biodiversity Domains  
    • 33. The 3 Domain System Unit 4 – Organizing Biodiversity
      • includes
      • Protists
      • Fungi
      • Plants
      • Animals
      http://student.ccbcmd.edu/courses/bio141/lecguide/unit1/3domain/3domain.html
    • 34. The 3 Domain System Unit 4 – Organizing Biodiversity http://student.ccbcmd.edu/courses/bio141/lecguide/unit1/3domain/3domain.html
    • 35. The 3 Domain System
      • Three-domain system
        • Based on rRNA
        • Domain Bacteria
          • “ normal” bacteria
        • Domain Archae
          • Archaebacteria that survive in very harsh environments
        • Domain Eukarya
          • Eukaryotic organisms
      Unit 4 – Organizing Biodiversity
    • 36. The 3 Domain System
      • Domain Bacteria (“true” bacteria such as E. coli, Lactobacillus bulgaris, and Cyanobacteria ). Members of this domain are composed of prokaryotic cells, but they are biochemically and genetically distinct from the Archaeans in that their cell walls contain the protein peptidoglycam.
      Unit 4 – Organizing Biodiversity
    • 37. The 3 Domain System
      • Domain Archaea (organisms that live in extreme environments such as Acidianus, Thermodiscus, and Methanobacteriales ). Members of this domain are composed of prokaryotic cells, but they are biochemically and genetically distinct from the Bacteria in that their RNA contains distinct sequences. In fact, Archaeans are probably more closely related to humans than they are to bacteria.
      Unit 4 – Organizing Biodiversity
    • 38. The 3 Domain System
      • Domain Eukaraya (all eukaryotes including animals, plants, fungi and protists). Members of this domain are composed of eukaryotic cells that contain nuclei and membrane-enclosed organelles such as mitochondria and chloroplasts.
      Unit 4 – Organizing Biodiversity
    • 39. Bacteria & Archaea Unit 4 – Organizing Biodiversity
    • 40. Domain Bacteria
      • Biology of bacteria
        • 3 basic shapes-cocci, bacilli, spirillum
          • Bacilli and cocci may be solitary or in clusters or chains
        • Bacterial structure
          • Plasma membrane
          • Many have a cell wall containing peptidoglycans (a particular protein)
      Unit 4 – Organizing Biodiversity
    • 41. Typical Bacterial Cell Unit 4 – Organizing Biodiversity
    • 42.
      • Bacterial reproduction
        • Binary fission
        • after a period of growth a bacterial cell can replicate its genome and divide in half asexually
      Domain Bacteria Unit 4 – Organizing Biodiversity
    • 43.
      • Bacterial reproduction
        • No sexual reproduction, but three mechanisms of genetic recombination
          • Conjugation -”male” cell passes DNA to “female” through a sex pillus
          • Transformation -bacterium takes up DNA from environment released by dead bacteria
          • Transduction -viruses carry bacterial DNA from cell to cell
      Domain Bacteria Unit 4 – Organizing Biodiversity
    • 44.
      • Bacterial metabolism
        • Most are heterotrophic
        • Some are photosynthetic
          • Cyanobacteria - have chlorophyll a and undergo photosynthesis
        • Some are chemosynthetic
      Domain Bacteria Unit 4 – Organizing Biodiversity
    • 45.
      • Biology of archae
        • Very different from the bacteria
        • Archaea are more closely related to Eukarya based on nucleic acid similarities
        • Inhabit extreme environments
          • Extreme thermophiles - live in extremely high temperatures
          • Extreme thermoacidophiles - line in habitats with high temperature and low pH
          • Halophiles - live in salty habitats
          • Methanogens - anaerobic environments
      Domain Archaea Unit 4 – Organizing Biodiversity
    • 46.
      • Archaeal Structure & Metabolism
      • Structure
          • DNA genome is a single, closed circular molecule
          • Chemical characteristics make them acid and heat tolerant
          • Reproduce asexually by binary fission
      • Metabolism
          • Some are heterotrophs, some are autotrophs
      Domain Archaea Unit 4 – Organizing Biodiversity
    • 47. Domain Eukaraya Unit 4 – Organizing Biodiversity
      • Protists
      • Fungi
      • Animals
      • Plants
    • 48. Protists
    • 49. Protists
      • Most are unicellular; microscopic
      • Protists have a nucleus with a membrane
        • Eukaryotic
      • The modern classification of protists includes three main groups:
        • plant-like protists--six major phyla
        • animal-like protists--four major phyla
        • Fungus-like protists--three major phyla
      • Autotrophic or heterotrophic
    • 50. Protists
      • Plant-like protists can photosynthesize because they have organelles with chlorophyll.
      • Animal-like protists are also known as protozoa. They are animal-like because they do not have cell walls and they are heterotrophic.
      • Fungus like protists (also called slime moulds) are similar to fungi in that they live in cool, shady, and moist environments. They obtain their food from dead and decaying plant material.
    • 51. Fungi
    • 52. Fungi
      • Plants and fungi are similar in that they are both eukaryotic and have cells with cell walls, and they are both stationary. There are differences between true plants and fungi, however, that place fungi in their own kingdom. Fungi
        • do not photosynthesize
        • do not have true root and systems
        • do not contain cellulose in their cell walls
        • cells are multinucleate
    • 53. Fungi
      • Some fungi are microscopic; others weigh several kilograms.
      • They obtain their food by absorbing nutrients from organic material.
      • They produce thread-like filaments called hyphae that extend out into the material to absorb food. As the hyphae grow, they form a mass called mycelium. Mycelium is often not visible because it is beneath the surface.
    • 54. Fungi
      • Most fungi do not have cell walls or only partial cell walls between "compartments;" therefore the cytoplasm is continuous and the cells have multiple nuclei.
      • The cell walls are composed of chitin, not cellulose.
      • Reproduction can be asexual or sexual by means of spores.
    • 55. Fungi
      • Fungi or their spores are almost everywhere.
      • 4 main phyla of fungi:
          • Mushrooms belong in the kingdom Fungi.
          • The sac fungi--yeasts, morels, and truffles.
          • The conjugation fungi, or moulds, are another major group.
          • The fourth group is called the imperfect fungi and includes all fungi that are not known to have a sexual reproductive phase.
    • 56. Kingdom Animalia
    • 57. Kingdom Animalia
    • 58. Evolutionary trends among animals
      • Overview
        • Heterotrophic, acquire food by ingestion
        • Locomotion by means of muscles
        • Multicellular, high degree of cell specialization
        • Adult is diploid
        • Reproduction usually sexual, with embryo undergoing developmental stages
      • Invertebrates- lack an endoskeleton of bone or cartilage
        • All but one animal phylum are invertebrates
      • Vertebrates- have an endoskeleton of bone or cartilage
    • 59. Animal Diversity
    • 60. Evolutionary trends among animals cont’d.
      • Level of organization
        • Cellular - no true tissues; sponges
        • Tissue -have ectoderm and endoderm; cnidarians like hydra
        • Organ -have ectoderm, endoderm, and mesoderm; majority of animals
      • Type of body plan
        • Sac-plan - incomplete digestive system; cnidarians
        • Tube-within-a-tube plan -inner tube is digestive system, outer tube is body wall; two openings
    • 61. Evolutionary trends among animals cont’d.
      • Type of symmetry
        • Asymmetrical -no particular symmetry
        • Radial symmetry -circular organization, can be bisected in any plane to produce mirror images
        • Bilateral symmetry -has definite right and left halves; only a cut down the midline will produce mirror images
      • Type of body cavity
        • Coelom -cavity that contains organs, and is lined with mesoderm
        • Acoelomate -lacks a body cavity
        • Pseudocoelomate -body cavity incompletely lined with mesoderm
    • 62. Evolutionary trends among animals cont’d.
      • Segmentation
        • Repetition of body parts
        • Molluscs and echinoderms are unsegmented coelomates
        • Annelids, arthropods, and chordates are segmented coelomates
        • Leads to cephalization and specialization of body parts
      • Jointed appendages
        • Specialized for locomotion
        • In arthropods, may be adapted as mouth parts
    • 63. Evolutionary tree
    • 64.  
    • 65.
      • Phylum Porifera (Sponges)
        • Multicellular; body a loose aggregate of cells
        • All aquatic, mostly marine
        • Body with pores, canals, and chambers for circulation of water
          • Epidermis of flat cells, some with contractile fibers
          • Middle layer is semi-fluid, with wandering amebocytes
          • Inner layer of choanocytes -flagellated to move water
        • Filter feeders- intracellular digestion
          • Cells get food from circulating water
        • Classified based on skeleton-composed of spicules
        • Reproduction-asexual by budding, sexual by fusion of gametes
    • 66. Sponge
    • 67.  
    • 68.
      • Phylum Cnidaria
        • Multicellular, tubular or bell-shaped animals-radial symmetry
        • All aquatic, mostly marine
        • 2 germ layers during development-tissue level
        • Nematocysts -stinging cells unique to cnidarians
        • 2 body types- polyps and medusae
          • Life cycle alternates between both forms in some; in others one form is reduced or absent
        • Gastrovascular cavity -sac-like body plan
        • Includes corals, jellyfish, and hydrozoans
          • Corals- polyps
          • Jellyfish-medusae
          • Hydrozoans-may have both forms
        • Can reproduce sexually and asexually (budding)
    • 69. Cnidarian Diversity
    • 70.  
    • 71.
      • Phylum Platyhelminthes (Flatworms)
        • Bilateral symmetry, three germ layers, acoelomate
        • Mesoderm gives greater complexity
          • Muscles, excretory, reproductive, and digestive systems in some
          • Respiration & circulation by diffusion
        • Planarians-free-living flatworms (Class Turbellaria)
          • Live in freshwater, feed on small living and dead organisms
          • Flame cells- excretion
          • Ladder-like nervous system- anterior ganglia and eyespots
            • Feed through muscular pharynx
            • Auricles-chemosensitive
          • 3 muscle layers- circular, longitudinal, and diagonal-more complex movements
          • Cephalization -has an anterior end and a posterior end
          • hermaphroditic
    • 72. Planarian Unit 2 - Biodiversityx
    • 73.
      • Flatworms cont’d.
        • Parasitic flatworms-two classes: tapeworms (Cestoda) and flukes (Trematoda)
          • Tapeworms-internal parasites as adults
          • Flukes-parasites of many species
    • 74.  
    • 75.
      • Phylum Nematoda (Roundworms-) Pseudocoelomates
        • Tube-within-a-tube body plan and a body cavity are first seen in this group
          • 2 openings, mouth and anus
          • Body cavity is a pseudocoel -filled with fluid, acts as hydrostatic skeleton
          • Many species; some are free-living in soil and water, others are parasitic
    • 76.
      • Parasitic roundworms
        • Ascaris
          • Move with whip-like motion
          • Intestinal parasites in many animal species
          • Females are much longer than males and highly prolific
          • Eggs enter host in uncooked vegetables, soil, or feces
            • Larvae burrow out of intestine and migrate to heart and lungs
            • Larvae are coughed up and swallowed
            • Mature to adults in intestines
    • 77.  
    • 78. Phylum Mollusca: Coelomates
      • Molluscs are a large and diverse group
        • Bilateral symmetry, three germ layers, organ level of organization, tube-within-a-tube body plan
        • 3 body parts
          • Visceral mass -includes most organs
          • Foot -muscular portion used for locomotion
          • Mantle -covering that envelopes visceral mass
            • Mantle cavity-space between the two folds of the mantle
            • Mantle may secrete a shell
        • Radula -rasping organ for feeding
    • 79. Diversity of Molluscs
    • 80.  
    • 81. Phylum Annelida: segmented worms
      • Annelids
        • Segmented worms
          • Tube-within-a-tube body plan-segmentation allows specialization of systems
            • Pharynx, esophagus, crop, gizzard, intestine, accessory glands
            • Longitudinal and circular muscles in each segment
            • Closed circulatory system with pumping hearts
            • Nervous system consists of brain, ventral nerve cord, and ganglia in each segment
            • Excretory system consists of nephridia in most segments
    • 82. Annelids: segmented worms cont’d .
      • Earthworms-Class Oligochaeta
        • Few setae per segment
        • No obvious head
        • Gas exchange across body wall
        • Feed on leaves and other organic matter
          • Food is drawn into mouth by muscular movements
          • Digestive tract has a large surface area
    • 83. Earthworm, Lumbricus
    • 84. Annelids: segmented worms cont’d.
      • Segmentation in earthworms
        • External segmentation evident by body rings
        • Internal segmentation by septa
        • Ventral nerve cord has ganglionic swellings in each segment
          • Lateral nerves extend from ganglions
        • Paired nephridia in each segment-2 openings
        • Blood moves anteriorly in dorsal vessel
          • Enters pumping vessels-”hearts”
          • Pump blood to ventral vessel-blood then moves posteriorly
          • Branches in each segment
    • 85. Annelids: segmented worms cont’d.
      • Reproduction in earthworms
        • Hermaphroditic
          • Male organs- testes, seminal vesicles, sperm ducts
          • Female organs-ovaries, oviducts, seminal receptacles
    • 86. Annelids: segmented worms cont’d.
      • Reproduction in earthworms
        • Hermaphroditic
          • Male organs- testes, seminal vesicles, sperm ducts
          • Female organs-ovaries, oviducts, seminal receptacles
    • 87. Annelids: segmented worms cont’d.
      • Reproduction in earthworms
        • Hermaphroditic
          • Male organs- testes, seminal vesicles, sperm ducts
          • Female organs-ovaries, oviducts, seminal receptacles
    • 88.  
    • 89. Phylum Arthropoda
      • Arthropods
        • Jointed appendages
          • Walking, swimming, reproduction, eating, sensory reception
        • Exoskeleton of chitin
          • Must undergo molting to allow growth
        • 3 body regions
          • Head, thorax, abdomen
        • Well-developed nervous system
          • Brain and ventral nerve cord
          • Sense organs-compound eyes, antennae
    • 90. Arthropod Diversity
    • 91. Arthropod Diversity cont’d.
      • Crustaceans- Subphylum Crustacea
        • Barnacles, shrimps, lobsters, crabs, crayfish, sowbug
        • Generalized structure-fused cephalothorax
          • Head has compound eyes and 5 pairs of apendages
            • First 2 pairs are antennae
            • Other 3 pair are mouth parts
          • Thorax has 5 pair of appendages-walking legs
            • 1 st walking leg has a pinching claw
            • Gills are situated above the walking legs
          • Abdomen
            • Last 2 segments have uropods and telson
    • 92. Arthropod Diversity cont’d.
      • Crayfish cont’d.
        • Internal organs
          • Digestive system-stomach (2 part), green glands (waste excretion)
          • Vascular system-heart pumps blood
          • Nervous system-brain and ventral nerve cord with segmental ganglia
          • Sexes separate
    • 93. Male crayfish, Cambarus
    • 94. Arthropod Diversity cont’d.
      • Insects
        • Largest and most diverse group
        • General structure
          • Head-a pair of compound eyes, several simple eyes, a pair of antennae, mouthparts adapted to specific way of life
          • Thorax- 3 pairs of legs and wings if present
          • Abdomen-contains internal organs
        • Grasshopper
          • 3 rd pair of legs is adapted for jumping
          • 2 pairs of wings
          • Tympanum on side of first segment of abdomen
          • Ovipositor of females- for digging a hole to lay eggs in
    • 95. Arthropod Diversity cont’d.
      • Grasshopper cont’d.
        • Internal organs
          • Digestive system-stomach, intestine, rectum, anus
          • Excretory system-Malpighian tubules
            • Uric acid-nitrogenous waste
          • Respiratory system-spiracles lead into trachae
            • Air pumped by contraction and relaxation of body wall
          • Circulatory system-heart pumps hemolymph into aorta, leads to a hemocoel
            • Hemolymph has no specialized pigment and is colorless
    • 96. Arthropod Diversity cont’d.
      • Grasshopper cont’d.
        • Reproduction-adapted to terrestrial life
          • Male has a penis which is inserted into female
          • Female has seminal receptacles which store sperm
          • Internal fertilization protects zygotes and gametes from drying
          • Female deposits fertilized eggs into ground
        • Metamorphosis -change in form and physiology that occurs as a larva becomes and adult
          • Immature grasshopper- nymph
    • 97. Female Grasshoppers
    • 98. Arthropod diversity cont’d.
      • Comparison of grasshopper and crayfish
        • Grasshopper adapted for terrestrial life, crayfish adapted for aquatic life
          • Crayfish have gills, grasshopper has spiracles and trachae
            • Crayfish require oxygen-carrying pigment to carry oxygen to cells
            • Oxygen diffuses directly through spiracles and trachae to reach cells so no pigment needed
          • Grasshopper has tympanum for reception of sound
            • Penis for passing sperm to female to prevent drying out
          • Crayfish utilize uropods when swimming, grasshopper has legs for hopping and wings for flying
    • 99.  
    • 100. Phylum Echinodermata
      • Characteristics
        • All saltwater aquatic organisms
        • Endoskeleton of spiny plates
          • Spines protrude through skin
        • Many have radial symmetry
          • Larval stage often bilaterally symmetrical
        • Very diverse group
          • Sea lilies- class Crinoidea
          • Sea cucumbers-class Holothuroidea
          • Brittle stars-class Ophithuroidea
          • Sea urchins and sand dollars- class Echinoidea
          • Sea stars- class Asteroidea
    • 101. Echinoderm Diversity
    • 102. Echinoderms cont’d.
      • Sea stars
        • Found along shorelines on rocky surfaces
        • 5-rayed body with mouth on underside and anus on upper side
          • On oral surface, each arm has an ambulacral groove surrounded by tube feet
          • Each arm has a coelomic cavity with digestive glands and gonads
        • Structures project through skin
          • Spines for protection
          • Pedicelleriae -around base of each spine, keep body surface free of debris
          • Skin gills -extensions of skin for gas exchange
    • 103. Echinoderms cont’d.
      • Sea stars cont’d
        • Feeding
          • Opens bivalve with its tube feed
          • Everts cardiac stomach through open shell and releases enzymes
          • Digested food taken in and digestion completed in pyloric stomach
          • Intestine is very short and terminates at anus on upper surface
        • Nervous system-no central brain
          • Central nerve ring gives off branches to each arm
          • Eyespot at tip of each arm
    • 104. Echinoderms cont’d.
      • Sea stars cont’d.
        • Water vascular system-locomotion by tube feet
          • Water enters through madreporite on aboral side
          • Madreporite leads into stone canals, and these lead into radial canals in each arm
          • Water is pumped into tube feet by the ampulla which lie along ambulacral groove on each arm
          • Suction is created by each small foot
        • Reproduction is both sexual and asexual
          • A body fragment, if large enough, can regenerate an entire animal
          • Gonads produce gametes,
            • Bilateral symmetry in larva
    • 105. Sea Star Anatomy
    • 106.  
    • 107.  
    • 108. Chordates
      • Evolutionary trends among Chordates
        • Invertebrate chordates- tunicates and lancelets
        • Vertebrate chordates- fishes, amphibians, reptiles, birds, mammals
          • Cartilaginous fish-first to develop jaws
          • Some early bony fish had lungs
          • Amphibians-first to have jointed appendages and invade land
          • Reptiles, birds, mammals- terrestrial adaptations for reproduction
            • Reptiles, birds- amniotic egg for development outside the body
            • Mammals- placenta and internal development
    • 109. Evolutionary Tree of Chordates
    • 110.  
    • 111. Chordates
      • Invertebrate chordates
        • Tunicates-the sea squirts
          • Subphylum Urochordata
            • Larva is bilaterally symmetrical and has 4 chordate characteristics
            • Adults are sessile, thick-walled, sac-like organisms
              • The only chordate characteristics in the adults are pharynx and gill slits
            • Have an outer tunic and 2 siphons which can squirt water
            • Live in ocean and are filter-feeders
            • Possibly a tunicate larva became sexually mature and gave rise to a fish-like vertebrate?
    • 112. Chordates
      • Invertebrate chordates cont’d.
        • Lancelets
          • Knife-shaped bodies a few centimeters long
          • Live in shallow coastal waters
          • Retain all 4 chordate characteristics as an adult
          • Segmentation is present
            • Muscles are segmentally arranged
            • Nerve cord has branches
    • 113.  
    • 114. The Chordates
    • 115. Vertebrates
      • Overview of the vertebrates
        • Have 4 chordate characteristics at some point in life
        • Distinguishing features
          • Living endoskeleton of cartilage or bone
          • Closed circulatory system with pumping heart
          • Paired appendages
          • Efficient respiration and excretion of wastes
          • High degree of cephalization with well-developed sense organs
    • 116.  
    • 117. Vertebrates
      • Fishes: first jaws and lungs
        • 3 groups of fishes: jawless, cartilaginous, bony
          • Cartilaginous and bony have true jaws with teeth
            • Evolved from first pair of gill arches
            • 2 nd pair of gill arches form support structures for jaws
            • Jaws allow predatory way of life
            • All fish are ectothermic - body temperature matches the environment
          • Adapted to life in water
            • Sperm and eggs released into water, fertilization external
            • Zygote develops into swimming larval form
              • Independent from adult for support
              • Develops into adult
    • 118. Vertebrates
      • Jawless fish
        • Superclass Agnatha- hagfish and lampreys
        • Cylindrical body shape with smooth, scaleless skin
        • No jaws, no paired fins
        • Hagfish-scavengers
        • Lampreys- parasitic
          • Mouth modified to form a sucker
          • Attach to other fish
          • Water moves in and out of gills directly and not through mouth as in other fish
    • 119. Vertebrates
      • Cartilaginous fish
        • Class Chondriicthyes- sharks, skates, rays
          • Endoskeleton of cartilage
          • Dermal placoid scales -gives body surface a “sandpaper-like” feel
          • Gills open, lack operculum (gill flap)
          • Efficient predators
            • Can sense electrical currents in water which indicate presence of prey
            • Lateral line system -sense pressure created by prey nearby
            • Well-developed sense of smell- sharks can detect 1 drop of blood in 25 gallons of water!
    • 120. Vertebrates
      • Bony fishes
        • Class Osteichthyes-most numerous and diverse of all vertebrates
          • Ray-finned fish-paired fins supported by bony rays; have jaws and skeletons of bone
            • Swim bladder- buoyancy organ
            • Streamlined body shape
            • Skin covered by bony epidermal scales
            • Water pumped across gills by an operculum
              • Enters through mouth, exits across gills
            • Blood pumped by heart with nondivided 2 chambered heart
          • Lobe-finned fish-fleshy appendages could be adapted for locomotion on land
            • Most had lungs
    • 121. Jawed fishes
    • 122.  
    • 123. Vertebrates cont’d.
      • Amphibians: jointed appendages
        • Class Amphibia- salamanders, frogs, toads, newts
          • Tetrapods, jointed appendages, ectothermic
          • Eyelids keep eyes moist, ears, larynx for vocalization
          • Larger brain than in fish
          • Small lungs present in adults; gas exchange also occurs across moist skin
          • 3-chambered heart-2 atria and a ventricle
            • Rt atrium receives deoxygenated blood from body
            • L atrium receives oxygenated blood from lungs
            • Blood mixes in ventricle
          • Metamorphic life cycle- larval stages in water, adults on land
            • Reproduction generally occurs in water
    • 124. Frog Metamorphosis
    • 125.  
    • 126. Vertebrates
      • Reptiles: amniote egg
        • Class Reptilia- turtles, tortoises, snakes, lizards
          • Extinct reptiles include mammal-like reptiles and dinosaurs
            • Evidence suggests birds are “feathered dinosaurs”
            • A common reptilian ancestor most likely gave rise to modern reptiles, birds, and mammals
          • Most are tetrapods; ectothermic but can regulate temperature through behavior (ex: basking)
          • Rib cage to protect organs and expands to inflate lungs
          • Dry skin covered with protective scales
          • Amniote egg covered with leathery shell
          • 3-chambered heart (division between ventricles incomplete) in most; true 4 chambered heart in some
          • Well-developed sense organs: snakes have tongue modified as sense organ
    • 127. The tongue as a sense organ
    • 128. The reptilian egg allows reproduction on land
    • 129.  
    • 130. Vertebrates
      • Birds: feathers
        • Feathers are modified scales; legs of birds have scales
        • Amniote egg with a hard shell
        • Adaptations for flight
          • 4-chambered heart - more efficient oxygen delivery
          • Endothermic -regulate body temperature above ambient
          • System of air sacs and one-way air flow through respiratory tract - increased efficiency of gas exchange
          • Forelimbs modified for flight -wings
          • Well-developed nervous system and sense organs
            • Navigational senses
          • Ritualized courtship , young require parental care
            • Cloaca- common urogenital opening
    • 131. Vertebrates
      • Birds, cont’d.
        • Classification
          • Based on beak and foot types
          • Also on habitat and behavior to a lesser degree
          • Birds of prey- long talons, notched beaks
          • Shorebirds- long, slender bills and long, stilt-like legs
          • Woodpeckers- sharp, chisel-like bills, grasping feet
          • Waterfowl-webbed toes and broad, scooping bills
          • Penguins- wings modified as paddles
          • Songbirds-perching feet
    • 132.  
    • 133.  
    • 134. Mammals
    • 135. Vertebrates
      • Mammals: hair and mammary glands
        • Endothermic, maintain relatively constant internal temperature
          • Hair provides insulation to preserve body heat
          • Efficient circulatory and respiratory systems to supply muscles that generate heat
            • 4-chambered heart
            • Circulatory system has 2 separate circuits for oxygenated and deoxygenated blood
          • Mammary glands allow care for young without having to leave them
          • Internal development in most with birth of live young
        • 3 groups- monotremes, marsupials, placentals based on how they reproduce
    • 136. Vertebrates
      • Monotremes
        • Have a cloaca like birds- common urogenital opening
        • Egg-laying mammals- lay a hard-shelled egg
        • Spiny anteater and duck-billed platypus
          • Both found in Australia
        • Both males and females have modified sweat glands and secrete milk onto body surface
          • Babies lick up the milk
    • 137. Vertebrates
      • Marsupials
        • Begin development within female’s body, born very immature and development is completed within a pouch
          • Attach to nipples of mammary glands within the pouch
        • Virginia opposum is the only marsupial species north of Mexico
        • Australian species- no competition from placentals
          • Adaptive radiation gave rise to many marsupial species
    • 138. Monotremes and Marsupials
    • 139. Vertebrates
      • Mammals cont’d.
        • Placental mammals
          • Extraembryonic membranes of reptilian egg are modified as placental membranes
          • Adapted for active life on land
            • Well-developed brain and sense organs
            • Limbs that allow rapid movement
            • Lungs expanded by rib cage and a diaphragm
            • 4-chambered heart
            • Internal body temperature is constant-allows optimum nerve and enzyme functions
            • Hair- insulates body
    • 140. Vertebrates
      • Placental mammals cont’d.
        • Differentiated teeth-incisors, canines, premolars, molars
          • Shape and size of teeth may determine type of food eaten
        • Classification of placental mammals is on methods of obtaining food and mode of locomotion; for example:
          • Order Chiroptera- bats; wings supported by digits for flight
          • Order Perissodactyla-horses; long, hoofed legs for speed
          • Order Cetacea-whales; paddle-like forelimbs
    • 141. Placental Mammals
    • 142. Evolutionary history of plants
      • Overview
        • Multicellular, photosynthetic eukaryotes
        • Believed to have evolved from a freshwater green alga
          • Plants and green algae contain chlorophyll a and b
          • Both store carbohydrates as starch
          • Both have cell walls of cellulose
        • 4 evolutionary events in evolution of plants
          • Development of embryo protection
          • Development of vascular tissue
          • Development of seeds
          • Development of flowers
    • 143.  
    • 144. Evolutionary history of plants cont’d.
      • Alternation of generations
        • Characteristic life cycle of plants
          • Two multicellular stages, each producing the other
            • One is haploid- gametophyte
            • The other is diploid- sporophyte
          • Sporophyte produces haploid spores by meiosis
            • Each spore develops into a gametophyte
          • Gametophyte produces gametes by mitosis
            • After fertilization, the embryo develops into a new sporophyte
          • In primitive plants the gametophyte is dominant, while in more advanced plants the sporophyte is dominant
            • Only the sporophyte develops vascular tissue
    • 145. Alternation of Generations
    • 146. Alternation of Generations
    • 147. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Gamete fusion 2 n Zygote 2 n Embryo Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 148. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n )
    • 149. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n )
    • 150. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia
    • 151. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia
    • 152. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia 2 n Spore mother cell
    • 153. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia 2 n Spore mother cell
    • 154. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia 2 n Spore mother cell Meiosis
    • 155. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia 2 n Spore mother cell n n n n Spores Meiosis
    • 156. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia 2 n Spore mother cell n n n n Spores Meiosis
    • 157. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 158. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 159. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Gametophyte ( n ) Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 160. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Gametophyte ( n ) Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 161. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Gametophyte ( n ) Egg Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 162. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Egg Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 163. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 164. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 165. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Gamete fusion Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 166. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Gamete fusion 2 n Zygote Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 167. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Gamete fusion 2 n Zygote Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 168. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Gamete fusion 2 n Zygote 2 n Embryo Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 169. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Haploid Diploid Mitosis Gametophyte ( n ) Sperm Egg Gamete fusion 2 n Zygote 2 n Embryo Sporophyte (2 n ) Sporangia Spore 2 n Spore mother cell n n n n Spores Meiosis
    • 170. Evolutionary history of plants cont’d.
      • Alternation of generations cont’d.
        • Physical appearance of generations differs greatly
          • Ferns- gametophyte is small, heart-shaped independent structure
            • Archegonia are the female structures of the gametophyte
            • Antheridia are the male structures-swimming sperm are produced
          • Flowering plants- the female gametophyte is the embryo sac retained inside the sporophyte body
            • Pollen grain is the male gametophyte
    • 171. Size of the gametophyte versus the sporophyte
    • 172.  
    • 173. Nonvascular Plants - Mosses
    • 174. Nonvascular Plants
      • Overview
        • Lack vascular tissue-limits size and habitat
        • Do not have true roots, stems, or leaves
        • Gametophyte is the dominant generation
        • Sperm must swim to egg for fertilization
        • Sporophyte is attached to the gametophyte and derives nourishment from it
        • 3 separate divisions on nonvascular plants
          • Mosses, liverworts, hornworts
    • 175. Nonvascular Plants
      • Mosses
        • Reproduce both sexually and asexually
          • Asexually by fragmentation
          • Sexually by production of gametes in archegonia and antheridia
        • Gametophyte has 2 stages
          • Protonema -branching filaments of cells
          • Develops leafy shoots at intervals along protonema
          • Rhizoids anchor moss to substrate
        • Dependent sporophyte
          • Consists of foot, stalk, and capsule or sporangium
            • Produces wind-borne spores
    • 176. Moss Life Cycle
    • 177. Moss Life Cycle
    • 178.  
    • 179. Vascular Plants - Ferns
    • 180.
      • Overview
        • Ferns and fern allies
        • Have vascular tissue- xylem and phloem
        • True roots, stems, and leaves in most
        • Sporophyte is the predominant life cycle stage
          • Stage with vascular tissue so can exploit more habitats
          • Advantage to being diploid- 2 copies of each allele
      Seedless Vascular Plants
    • 181.
      • Ferns and their allies
        • Produce wind-borne spores for dispersal
        • Spores germinate forming a small gametophyte that is independent from the sporophyte for its nutrition
        • Swimming sperm travel to archegonium to fertilize egg
      Seedless Vascular Plants
    • 182.
      • Ferns
          • Most abundant in warm, moist, tropical regions
          • Leaves are called fronds
            • Immature leaves are called fiddleheads
            • Grow from rhizome
          • Dominant sporophyte stage
            • Produces wind-blown spores
          • Spore germinates and forms small gametophyte
            • Independent from the sporophyte
            • Swimming sperm produced by antheridia
            • Fertilization occurs in archegonia
      Seedless Vascular Plants
    • 183. Seedless Vascular Plants
      • Ferns cont’d.
        • Adaptations
          • True roots, stems, leaves
          • Gametophyte lacks vascular tissue so is water dependent
            • Sperm also need water film to swim
          • Sporophytes can spread to drier areas by vegetative reproduction
            • Rhizomes
        • Uses of ferns
          • Floral decorations
          • Ornamental landscape plants
          • Some species used as food
    • 184. Fern Life Cycle
    • 185. Seed Plants – Gymnosperms & Angiosperms
    • 186. Seed Plants
      • Overview
        • Gymnosperms and angiosperms are seed plants
        • Seed contains a sporophyte embryo and stored food
          • Allows survival until conditions are favorable for germination
        • Gymnosperms-ovule not completely enclosed by diploid tissue
        • Angiosperms-ovule completely enclosed within diploid sporophyte tissue (ovary) which becomes a fruit
    • 187. Seed Plants
      • Gymnosperms- conifers, gnetophytes, gingkophytes, and cycads
        • We will use the conifers as our example
          • Pines, spruces, firs, cedars, hemlocks, redwoods, cypresses
          • Cone-bearers
        • Exhibit heterospory
          • Two types of spores- produce two types of gametophytes, male and female
          • Pollen grains - male gametophyte
          • Pollination -deposition of pollen on a female gametophyte
          • Pollen tube -sperm pass through pollen tube to reach ovule
            • No water required as it is in previous groups
          • Female gametophyte develops within ovule
    • 188. Pine Life Cycle
    • 189. Pine Life Cycle
    • 190. Seed Plants
      • Adaptations of conifers
        • Adapted to cold, dry weather
        • Pollen cones and seed cones are adaptations to land
        • Needle-shaped leaves have small surface area-decreases water loss
          • Also have a thick cuticle and recessed stomata
    • 191. Conifers
    • 192. Seed Plants – Angiosperms
    • 193. Seed Plants
      • Angiosperms-flowering plants
        • Wide range of habitats
        • Two classes
          • Monocotyledones - monocots
          • Eucotyledones -eudicots
        • Classes are distinguished by
          • Number of cotyledons
          • Number of flower parts
          • Pattern of leaf venation
          • Arrangement of vascular bundles
          • Type of root system
        • These characteristics are summarized on the following slide
    • 194. Monocots and Dicots ( eudicots )
    • 195. Seed Plants
      • Angiosperms cont’d.
        • The flower
          • Flower parts
            • Receptacle -tip of stalk that bears flowers
            • Sepals -modified leaves that protect bud
            • Petals -modified leaves, may be colorful, collectively called the corolla
            • Stamens -male reproductive structures
              • Anther -pollen production
              • Filament
            • Carpels -female reproductive structures
              • Stigma -for reception of pollen
              • Style
              • Ovary -ovule production
    • 196. Generalized Flower
    • 197. Seed Plants
      • Flowering plant life cycle
        • Illustrated on the following slide
        • Microsporogenesis produces microspores
          • Microsporocyte in anther undergoes meiosis- produces 4 haploid microspores-each becomes a pollen grain (male gametophyte)
            • Inside pollen grain are 2 cells-1 is a tube cell and the other is a sperm cell
        • Megasporogenesis produces megaspores
          • Megasporocyte divides by meiosis- produces 4 haploid megaspores-3 will disintegrate leaving 1 functional megaspore
            • Megaspore divides by mitosis 4 times but in the last division 1 cell doesn’t undergo cytokinesis
              • Produces an embryo sac (female gametophyte) with 6 haploid cells and 1 large central cell with 2 nuclei
    • 198. Flowering Plant Life Cycle
    • 199. Flowering Plant Life Cycle http://www.sumanasinc.com/webcontent/animations/content/angiosperm.html
    • 200. Seed Plants
      • Life cycle of flowering plants cont’d.
        • Pollination and double fertilization
          • Pollen is deposited by wind, insects, birds, etc. on stigma
          • Pollen grain opens and the tube cell digests a pollen tube down the style
          • Sperm cell divides once by mitosis to produce 2 sperm
          • Sperm travel down pollen tube to the embryo sac
          • 1 sperm fertilizes the ovule (1 of the 6 haploid cells in the embryo sac) and the other 5 break down
          • The other sperm fertilizes the central cell which becomes the triploid endosperm
            • Endosperm is food source within the seed
    • 201. Seed Plants
      • Adaptations of flowering plants
        • Flower structure, color, and scent co-evolves with pollinators
          • Insect, bird, and bat-pollinated plants have evolved showy flowers to attract pollinating species
            • Provides pollinator with nectar, fruit, etc.
              • Ex: hummingbirds are attracted to red, trumpet-shaped flowers
          • Wind-pollinated plants do not produce showy flowers
            • Generally have no petals or scent
            • Seeds are sent up on stalks into the path of the wind
        • Fruit-aids in seed dispersal
    • 202. Biological Keys
      • The identification of biological organisms can be greatly simplified using tools such as dichotomous keys .
      • Biologists use a dichotomous key to identify species that have already been discovered, described, classified, and named.
      • A dichotomous key is an organized set of couplets of mutually exclusive characteristics of biological organisms.
    • 203. Biological Keys
      • You simply compare the characteristics of an unknown organism against an appropriate dichotomous key.
      • These keys will begin with general characteristics and lead to couplets indicating progressively specific characteristics.
    • 204. Dichotomous Keys of Shoes
    • 205. Dichotomous Keys of Aliens
    • 206. Biological Keys
      • If the organism falls into one category, you go to the next indicated couplet. By following the key and making the correct choices, you should be able to identify your specimen to the indicated taxonomic level.
    • 207. Biological Keys
    • 208. Biological Keys
    • 209. Dichotomous Key Lab #32 Dichotomous Assignment
    • 210.  

    ×