Transcript Animals - Mt. SAC

Evolution of the Tetrapods
Evolution of the Tetrapods
The Origin of Tetrapods
• The first vertebrates on land were
amphibians in the _________(400 mya)
• Arose from the rhipidistian (a family of
lobed finned fish) (based on morhpology)
or a lungfish (DNA)
Origin of
Tetrapods
Classification
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Phylum: Chordata
Subphylum: Vertebrata
Superclass: Gnathostomata
Class: Amphibia
– Order: Urodela (Salamanders)
– Order: Anurans (Frogs and Toads)
– Order: Apodans (Caecilians)
Class: Amphibia
• Two lives
– refers to metamorphosis of many frogs
• Skin smooth and moist (cutaneous
respiration)
• _____ chambered heart with a double
circulation system
Order: Urodela
• 400 species
• Salamanders
• Retain their tail as
adults
• Limbs are at right
angles to the body
• Carnivorous
• Most have internal
fertilization using a
_____________
• Axolotl paedomorphosis
Order: Anurans
• 3500 species
• Frogs and Toads
• Lose their tail as
adults
• Hind limbs are
adapted for jumping
• Tongue connected to
front of mouth
• Secrete mucus
• __________
Fertilization
Order: Apodans
150 species
Caecilians
Legless and blind
Mostly Tropical
__________
Fertilization
• Usually give birth
to live young.
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Gas
Exchange
Conditions for Respiratory Surfaces
• Large surface area
• Thin
• Moist
Aquatic vs. Terrestrial
• Less than ____%
oxygen
• Oxygen amounts
decrease as the
temperature
increases
• Aquatic animals
use large amounts
of energy to obtain
oxygen (____%)
• About _____%
oxygen
• Developed
invaginations to
increase surface
area and decrease
evaporation
• Terrestrial animals
may use only 1% 2% of its energy to
obtain oxygen
Gills
• Found in echinoderms, mollusks,
annelids,
arthropods, some
vertebrates
• Countercurrent
Gas Exchange
Countercurrent Gas Exchange
• Maintains gradient over the whole length of
the capillaries
• Extracts ____% of the oxygen from the
water
Tracheal Systems
Diffusion Lungs
• Found in invertebrates
• Gas moved primarily by diffusion
– may be increased by body movement
• Modifications
– snails - cavity with gill modified into
lung
– scorpions and spiders - invaginations of
the abdomen
Ventilation
Lungs
• Found in
amphibians,
reptiles,
mammals and
birds
• Pharynx
• Larynx
• Trachea
• Bronchi
• Bronchioles
• Alveoli
Alveoli
Ventilating The Lungs
• _______ Pressure
Breathing
– pushes air down
trachea
– seen in frogs and
other
amphibians
• ________ Pressure
Breathing
– suction created
by diaphragm
– seen in
mammals
Negative Pressure Breathing
Evolution of the _________ Egg
• Allows animals to complete their
entire life cycle on land
• Has shell that retains water (or is
lost when kept inside mammals)
• Specialized extraembryonic
membranes (not part of the animal)
The Amniotic Egg
Evolution of the Amniotic Egg
• Amnion - Protects from dehydration
and mechanical shock
• Yolk Sac - Nutrient storage
• Albumin (egg white) - Nutrient
storage
• Allantois - stores waste, gas
exchange
• Chorion - gas exchange
• *** Good Essay….
Amniotes
How Reptiles differ from
Amphibians
• Tough, dry skin
• Amniotic egg
• Crushing or
gripping jaws
• Copulatory organs
• More efficient
circulatory system
with a higher blood
pressure
• More developed
lungs (thoracic
breathing)
• Better water
conservation
• Better body
support and limbs
• Better nervous
system
Classification
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Phylum: Chordata
Subphylum: Vertebrata
Superclass: Gnathostomata
Class: Reptilia (not real)
– Class: Testudines (Turtles and
Tortoises)
– Class: Spenodontia (Tuataras)
– Class: Squamata (Lizards and Snakes)
– Class: Crocodilia (Crocodiles and
Alligators)
Reptile Radiation
• Synapsids
(therapsids) led to
mammals
• Sauropsids
– _________
(turtles)
– _________
(all others)
Class: Testudines (Chelonia)
• Protective Shell
– Carapace (top)
– Plastron (bottom)
• Land and Sea Evolved on land
and returned to
water (lay eggs
on land)
Largest,
Leatherback
Sea Turtle
(2,000 lbs!)
Class: Testudines (Chelonia)
• No _____
• Most move legs
to breathe
• TDS (low:male
high:female)
Class: Sphenodontia
• ___________
– Two living species
(New Zealand)
– Not a True Lizard
(no external ears,
different teeth)
– Very Primitive
(similar to
mesozoic reptiles
– Well developed
eye below skin?
Class: Squamata
• Lizards
– geckos, iguanas,
skinks, chameleons
• terrestrial, burrowing,
aquatic, arboreal
• moveable eyelids (in
most)
• Paired copulatory
organs
Class: Squamata
• Tongue usually not
bifurcated
• Lower jaw loosely
connected to skull
• TSD (female to male)
• ______________
Class: Squamata
Class: Squamata
Class: Squamata
Gila Monster –
• One of three
poisonous lizards
• Protein in saliva
studied to treat
diabetes.
Class: Squamata
• Snakes
• Lack limbs
• Lack moveable
eyelids
Class: Squamata
• Bifurcated tongue
• _________ organ
• Pit Vipers (Loreal
Pits)
Class: Squamata
• Venom
– Viperidae (Folding
Fangs)
• Rattlesnakes
– Elapidae (Fixed
Front Fangs)
• Cobras, Sea Snakes,
Coral Snakes
– neurotoxic
– hemotoxic
Class: Squamata
Feeding
Adaptations
• Teeth curved and pointed inward
• Hinged __________ bone
• Bones of jaw are attached by
muscles and ligaments
• Moveable palate
• Elastic skin
• No sternum
• Largest living
reptiles
• Most closely
related to
dinosaurs
• Complete
secondary
________
• Four chambered
heart (?)
• Nest temperature
(female/male)
Class: Crocodilia
Dinosaurs and Pterosaurs
• Dinosaurs
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Ornithischian
Saurischian
Pterosaurs
flying reptiles
Animal Structure
and Function
(4th exam)
Animal Nutrition
Nutritional
Requirements
• Undernourished
– not enough
calories
• Overnourished
– too many calories
• ____________
– missing one or
more essential
nutrients
Essential Nutrients
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Essential
Essential
Essential
Essential
Amino Acids
Fatty Acids
Vitamins
Minerals
Essential Amino Acids
• Found in proteins
– 20 different types
• 8 essential in adult
humans (9 infants)
• all in animal proteins
• vegetarians need to
eat grains and beans
Histidine
__________ – Essential in infants
Essential Fatty Acids
• Unsaturated fatty acids
– used to make phospholipids for
membranes
Essential Vitamins
• Fat Soluble
– stored in fat
– ___________
• Water Soluble
– excreted in urine
– B complex and C
Essential Minerals
• Inorganic nutrients
– Calcium & Phosphorous
• bones
– Iron
• anemia
– Iodine
• thyroid hormones
– Sodium, Chlorine, & Potassium
• nerve function, water regulation
Food Types
• Heterotrophic
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Herbivores
Carnivores
Omnivores
Insectivores
Feeding Adaptations
• Suspension
Feeders
Feeding Adaptations
• Substrate Feeders
Feeding Adaptations
• Fluid Feeders
Feeding Adaptations
• Bulk Feeders
Intracellular Digestion
• Inside cells
• All animals
• Exclusive in:
– Protista
– Porifera
Extracellular Digestion
• Outside cells
• All animals above the sponges
• Two Types
– _________________
– _________________
Gastrovascular
Cavity
• One opening
• Found in
Cnidaria and
Platyhelminthes
Alimentary Canal
• Two openings
• Allows for
specialization
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Mouth
Pharynx
Esophagus
Crop
Gizzard
Stomach
Intestine
Anus
Mammalian Digestion
• Accessory Glands
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salivary glands
pancreas
liver (emulsification)
gallbladder
• Peristalsis
• Sphincters
• “Food”
– bolus
– acid chyme
– feces
Macromolecule Digestion
Mouth
Carbo Protein Nucleic Fat
Acids
Initial
Stomach
Initial
Intestine Main
Main
Initial
Main
Initial
Main
Dentition and Diet
• Nonmammal
vertebrates
• Carnivores
– canines
(grasping/puncturing)
– incisors (tearing)
– molars and premolars
• (crushing and grinding)
• Herbivores
• Omnivores
Digestive Tracts
• Carnivores
– ________
digestive
system
– small
cecum
• Herbivores
– ________
digestive
system
– large cecum