Transcript File

Evolution Unit
Evidence for Evolution
Diversity of Life
AP Biology Review
Another Resource: Biology Web Page
http://faculty.clintoncc.suny.edu/facul
ty/michael.gregory/default.htm
• Evidence for evolution
What types of evidence support an
evolutionary view of life?
• Mechanisms of evolution
– What is the role of natural selection in the process
of evolution?
– How are heredity and natural selection involved in
the process of evolution?
– What mechanisms account for speciation and
macroevolution?
– What different patterns of evolution have been
identified and what mechanisms are responsible
for each of these patterns?
Darwin’s Theory of Natural Selection
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Organisms reproduce others of their kind
More offspring than can survive to reproduce
There are variations within populations
Some variations are favorable
Organisms with the favorable variation will
survive to reproduce
• Over time, favorable adaptations make up
most of the population
The Evolving Understanding of
Evolution: Finding Evidence
• This reading discusses the evidence
that scientists use to show organisms
have evolved over time.
• There are 5 pieces of evidence
showing organisms have evolved
Fossil Record
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•
•
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Shows a tremendous variety of organisms
Organisms come and go
Reconstruct changes of organisms
Infer behaviors (ex: sharp teeth = carnivore)
Morphology
• Similar types of body structures
• Homologous Structures
– Show common ancestry
– Example: teeth of a bear and teeth of a dog
– Example: arm of a human and flipper of a whale
• Analogous Structure
– Common function but not a common anscestor
– Example: wings of a bird and wings of butterfly
Biochemical and Molecular
• Exact same chemical makeup in biomolecules
– Carbohydrates (sugars) – C,H,O
– Proteins (amino acids) – C,H,O,N,S
– Lipids (fats/oils) – C,H,O
– Nucleic acids (DNA, RNA) – C,H,O,P
• Similar metabolic processes from humans to
bacteria (same chemical reactions)
• Process of: DNA
RNA
protein
is the same
Embryology
• Embryos of fish,
lizards, turtles,
chickens, pig,
mice and humans
are very similar.
• Embryonic
pattern of
development
seems to be
retained in many
organisms.
Biogeographical data
• Organisms unique to a certain location that has
been isolated for a long time.
– Example: Madagascar has a variety of unique
organisms (lemurs)
• Organisms with very similar body plans are
found in different areas around the world.
– Example: Flightless birds (kiwi, ostrich, rhea, emu,
cassowary)
III. Organisms and Populations
• The relationship of structure to function is a
theme that is common to all organisms; the
interactions of organisms with their
environment is the major theme in ecology.
Kingdom Classification
Biology 1-2
Monera
Examples:
(BACTERIA)
E. coli
Streptococcus
Staphylococcus
Protista
Euglena
Amoeba
Paramecium
Fungi
Examples:
Mushrooms
Yeast
Bread Molds
Plantae
Animalia
Essential Vocabulary
• Unicellular:
– Composed of one cell
• Multicellular:
– Composed of many cells
• Autotroph:
– Makes its own food via
photosynthesis
• Hetertroph:
– Cannot make its owns
food
• Motile:
– Free moving
• Sessile:
– Permanently attached
• Asexual:
– One parent contributes
genes to offspring
• Sexual:
– Two parents contribute
genes to offspring
Essential Vocabulary (cont)
• Prokaryote:
– No “true” nucleus
• Eukaryote:
– Has a nucleus
Uni or
Multi
Monera Protista Fungi
Plantae Animal
Uni
Multi
Multi
Multi
Hetero
Auto
Hetero
Sessile
Sessile
Mostly
Motile
Mostly
Sexual
Mostly
Sexual
Mostly
Sexual
Euk
Euk
Euk
Auto or Hetero
Hetero
Uni
Hetero
Auto
Motile Motile Motile
Sessile Sessile Sessile
Asex or Asexual Mostly
Sex
Sexual
Pro or Pro
Euk
Eukary
• Why classify things?
– Organization
– Communicate in a common language about
specific organisms
• Who 1st classified?
– Aristotle
• What were his 2 group? The rules for getting
into the groups are:
1) Plants – kind of stem
2) Animal – where they lived (air, water, land)
• Why did this classification change?
– Not sufficient … too many organisms!
• In the 1700’s, who organized life by structural
features?
– Carolus Linnaeus
Species
Genus
Family
Order
Class
Phylum
Kingdom
• Naming of organisms has which two name?
– Genus and Species (example: Homo sapiens)
Kingdom
Description
Monera
Bacteria
Protista
Unicellular (one cell)
Fungi
Obtain nutrients through
absorption
Plants
Autotrophs
(photosynthesize)
Heterotroph (consumers)
Animals
• What is the new type of taxonomy called?
– Molecular taxonomy; compares DNA, RNA, protein
Human Classification
Classifcation Level
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• species
Human
• Animal
• Chordata (backbone)
• Mammalia (produce milk)
• Primate (opposable thumb)
• Hominidae (human-like)
• Homo (man)
• Sapiens (wise)
Human = H. sapiens
Diversity of Organisms
• Evolutionary patterns
– What are the major body plans of plants and
animals?
• Survey of the diversity of life
– What are representative organisms from the
Monera, Fungi, and Protista?
• Phylogenetic classification
– What are the distinguishing characteristics of each
group (kingdoms and the major phyla and
divisions of animals and plants)?
Plant Evolution
All plants derived from green algae
Terrestrial Adaptations
• Apical meristems
– Localized regions of cell division at tips of roots and
shoots
• Light and CO2 from shoots
• water/, mineral nutrients from roots
• Mutlicellular, Dependent Embryos
– Parent plant provides nutrients
• Alternation of Generations
– Two multicellular body forms alternate
• Haploid (n) Gametophyte generation
• Diploid (2n) Sporophyte generation
Adaptations (cont.)
• Walled spores produced in sporangia
– Sporangium protect spores
– Sporopollenin (most durable organic material known)
make walls of spores tough and resistant
• Multcelluar gametangia
– Archegonia = Female (egg)
– Antheridia = Male (sperm)
• Water conservation
– Cuticle (waxy covering on leaves and microbe protection)
– Stomata (pores on underside of leaf for gas exchange)
• Water transport (vascular plants)
– Xylem
• Water conducting tissue with lignified cells
• roots to shoots
– Phloem
• Sugar transporting tissue
• shoots to roots
• Secondary Compounds
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–
–
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Metabolic pathways to produce lipids, carbs, etc.
For defense: bitter taste, strong odors, toxins
Absorb harmful UV radiation
Medicinal uses for humans (ex: quinine for malaria)
Chemical signals in symbiotic relationships
• Rhizobium
bacteria
receives
signal from
the root which
helps direct
production of
enzymes that
establish the
root nodule
system used
in nitrogen
fixation.
Evidence for phylogenetic connection
between land plants and green algae
• Homologous chloroplasts
– Chlorophyll b and beta-carotene as
accessory pigments
– Thylakoids stacked as grana
• Homologous cellulose walls
• Homologous peroxisomes
– Anti-photorespiration enzymes
• Homologous sperm
• Molecular systematics
– DNA, rRNA, cytoskeletal proteins
Bryophytes - Mosses
• Nonvascular
• Seedless
• Male and Female Gametophytes
– Antheridia produce sperm
– Archegonia produce eggs
• Sporangium produces enormous #
of spores
– Release of spores can be
regulated to take advantage of
period ic wind gusts that can
carry spores long distances
• Protonemata increase surface
area, enhancing water absorption
• Rhizoids serve to anchor the plant
to the ground
• Gametophyte is the prevalent
generation
Pteridophytes - Ferns
• Vascular, Seedless
• More complex sporophyte with multiple sporangia have better chance of surviving
and reproducing despite possible destruction by herbivores
• Sporophyte is homosporous but the gametophyte has both male/female sex organs
– Sex organs mature at different times, ensuring cross-fertilization
– Sperm are flagellated (require moist environment to travel)
Seed Plants
• Reproductive adaptations
– Continued Reductions of the the Gametophyte
• Gametophyte is sheltered from drought and UV rays
– Advent of the seed
• Multicellular
• Sporophyte embryo packaged with food supply and
protective coat
• Megasporangia – megaspores – female gametophyte
• Can be carried far away from parents
– Evolution of pollen
• Microsporangia – microspores – male gametophyte
• Tough sporopollenin coats
• Fertilization no longer needs liquid-water
Gymnosperms (Conifers)
• Vascular w/seeds
• “naked seed”
– Lack enclosed
chambers (ovary)
– Develops on
sporophylls (leaf)
• Pine tree is sporophyte
• Sporangia packaged in
cones
• Heterosporous
– Male/female
gametophytes from
different spores
Angiosperms (flowering plants)
• Vascular w/ seeds
• Xylem cells (tracheids)
–
–
–
–
Water transport
Mechanical support
Fiber cells (support)
Vessel elements
• Shorter/wider/end-to-end
• Flowers
• Fruits (ovaries)
• Stamen (Male parts)
– Anther
• Produce pollen
– Filament
• Hold up anther
• Carpel
– Female parts
– Stigma
• Sticky residue captures pollen
– Style
• Leads to ovary
– Ovary
• Holds the eggs
• Sepals (typically green)
– Protect the floral bud
• Petals (colorful)
– Advertise the flower to insect
pollinators
• The peas are the seeds
• The pea pod is the fruit (ovary)
Plant Reproduction in Angiosperms
Development of Angiosperm Gametophytes
• Pollen grain
– Generative cell
• Becomes 2 sperm
– Male gametophyte
• Becomes the
pollen tube
• Embryo sac
(in ovule):
– 1 egg
– 2 polar nuclei
Double Fertilization
• Pollination
– Brings the male and female
gametophytes together
– Leads to fertilization
• Step 1
– Pollen grain lands on
stigma
– Pollen tube begins to grow
– Generative cell divides by
mitosis to make 2 sperm
• Step 2
– Tip of pollen tube enters the ovary
– Two sperm discharged within the embryo sac
• Step 3
– One sperm fertilizes the egg to form the zygote
– The other sperm combines with the two polar
nuclei to form a triploid (3n)
– The triploid becomes the endosperm (food storing
tissue of the seed)
Purpose of Double Fertilzation
• Ensures the
endosperm will
only develop in
ovules where the
egg has been
fertilized, thereby
conserving
resources for when
they are needed
Animal Evolution
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•
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Porifera
Cnidaria
Platyhelminthes
Nematoda
Rotifera
Annelids
Mollusca
Arthropoda
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•
•
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•
•
Echinodermata
Agnatha
Chondricthyes
Oseichthyes
Amphibia
Reptilia
Aves
Mammals
Porifera (pore-bearer) … Sponge
• Reproductive
– Asexual (budding,
fragmentation, regeneration)
– Sexual (flows through water)
• Digestive
• Respiratory
• Circulatory
– Oxygen obtained via flowing water
– Food flows in via water
– Only two cells thick
– Flowing water has oxygen that is
diffused into the cells
Cnidaria … hydras, jellies, anemomes, coral
• Reproductive
– Asexual (budding)
– Sexual
• Zygote, blastula,
polyp, medusae, jelly
• Respiratory
– Diffusion
• Digestive
– Muscle-like
contractile cells
– Enzymes
– Waste leaves mouth
• Circulatory
– Diffusion
Platyhelminthes … flatworm
• Reproductive
– Asexual
– Sexual
• Respiratory
– Diffusion
– Very flat body helps
• Digestive
– Incomplete pharynx leads to
gastrovascular cavity
– Enzymes
– Waste leaves the mouth
• Circulatory
– Diffusion
– Very flat body helps
Nematoda … roundworm
• Reproductive
– Sexual
• Eggs fertilized in
female body
• Respiratory
– Diffusion
• Digestive
– Complete
• Mouth, intestine, anus
• Circulatory
– Diffusion
Rotifera … tapeworm
• Reproductive
– Parthenogenesis
• Females develop
from unfertilized eges
• Digestive
– Complete
• Mouth, intestine, anus
– Sexual
• Respiratory
– Diffusion
• Circulatory
– Diffusion
Annelids … earthworm, leeches
• Reproductive
– Sexual
• Hermaphroditic but
must have partner
• Respiratory
– Diffusion across skin
(oxygen is dissolved
in water)
• Digestive
– Complete
• Muscular pharynx to
draw in soil, crop,
gizzard, intestine,
anus
• Circulatory
– Closed system
• Tiny blood vessels
• Muscular pumps
(hearts)
Mollusca … snails, clams, squid
• Reproductive
– Sexual
• Internal (squid, snail)
• External (clams)
• Respiratory
– Mantle cavity
• Feathery gills (water)
• Lungs (terrestrial)
• Digestive
– Complete
• Straight or coiled
(digests more)
• Circulatory
– Open - Gastropods
• Snail, slug
– Closed - Cephalopods
• Squid, Octopus
Arthropoda … Insects
• Reproductive
– Sexual
• Respiratory
– Spiracles, tracheal
tube, gas exchange
• Digestive
– mouth, esophagus, crop
(moistens food), gizzard
(grind), midgut
(enzymes), hindgut, anus
– Malpighian tubules
return water to the body
• Circulutory (Open)
– Dorsal heart, arteries,
body cavity, tissues,
sinuses, heart
Arthropoda … Arachnids
• Reproductive
– Sexual
• Respiratory
– Book lungs
• Increased surface area
• Digestive
– Mouth, stomach,
digestive enzymes,
anus
• Circulutory (Open)
– Dorsal heart, arteries,
body cavity, tissues,
sinuses, heart
Arthropoda … Crustaceans
• Reproductive
– Sexual
• Respiratory
– Gills
• Digestive
– Mandibles, stomach,
chitonous teeth,
enzymes, intestines,
anus
• Circulutory (Open)
– Dorsal heart, arteries,
body cavity, tissues,
sinuses, heart
Echinodermata … starfish
• Reproductive
– Asexual
• Regeneration
– Sexual
• Respiratory
– Water vascular
system
• Digestive
– Lower stomach
pushed out, enzymes,
body cavity, coelum,
intestine, anus
• Circulatory
– Water vascular
system
Chordates ... 4 embryonic traits
Agnatha – “jawless” fish
• What makes it different?
– Skeleton made entirely of cartilage
– Can be in larval stage for years
– Produces a slime that can suffocate other fish
(defense mechanism)
Chondricthyes … cartilaginous (sharks, rays)
• Reproductive
– Sexual
• Internal
• Respiratory
– Enters mouth
– Out gills
– Must keep moving
• Digestive
– Stomach, intestine,
spiral valve (increase
surface area for better
digestion), anus
• Circulatory
– Gills
– Blood
– 2-chambered heart
– Single loop
Osteicthyes … bony fish
• Reproductive
– Sexual
• External
• Respiratory
– Enters mouth
– To gills
– Can pump without
moving (nice when
hiding)
• Digestive
– Stomach, intestine,
anus
• Circulatory
– Gills
– Blood
– 2-chambered
– Single loop
Amphibia … dual life
• Reproductive
– Sexual
• external
• Respiratory
– Lungs
– Gills (larval stage)
– Skin – diffusion
(must be moist)
• Digestive
– Mouth, esophagus, stomach,
small and large intestine, anus
– Liver (produce bile)
– Pancreas (release dig. enzymes)
• Circulatory
– Blood
– 3-chambered
– Double loop
Reptilia – snakes, alligators
• Reproductive
– Sexual
• internal
• Respiratory
– Lungs
• Large surface area
• Digestive
– Enzymes in stomach
– Slow process
• Circulatory
– Blood
– 3-chambered
– Ventricle almost
divided in 2
Aves … birds
• Reproductive
– Internal
– Incubation of egg
• Respiratory
– Lungs
– One-way flow
• Mouth, trachea,
posterior air sacs,
anterior air sacs,
mouth
• Digestive
– Saliva, esophagus, crop
(store/moisten), gizzard
(grind), instestines (villi
to increase surface area),
anus
• Circulatory
– Rapid heart beat,
high blood pressure
– 4-chambered
Mammalia … you and your dog
• Reproductive
– sexual
• Respiratory
– Lungs
• Digestive
– Complete
• Circulatory
– 4-chambered