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53 Cards in this Set

  • Front
  • Back

1. Egg shell

2. Albumen

3. Chorion

4. Allantois

5. Yolk

6. Yolk sac

7. Amnion

8. Amniotic cavity

9. Embryo

Benefits of placenta

Greater protection

Greater mobility

Favors evolution of few large offspring

How does the placenta form?

Forms from embryonic/maternal tissues

Who are the amniotes?



Temporal Feresteral

Openings in skull behind eyes

Diapsid vs. Syapsid vs. Anapsid

Diapsid: 2 openings in skull (most reptiles)

Synapsid: 1 opening in skull (humans)

Anapsid: 0 openings in skull (turtles)

Reptile Traits


Amniotic egg


3-4 chambered

Flight (in birds)

Benefit of scales (scutes)

Horny scales composed of keratin

Used for waterproofing

Traits of Lepidosaurs

Replaceable overlapping scales

Limbs are reduced/lost





Self amputation of limbs (tail in lepidosaurs)


Pair of retractable sex organs near tail


Female cloning of egg that can be fertilized by polar bodies

Testudinia Traits

0 temporal fenesterae

Presence of shell

Terrestrial (tortoises) and aquatic (turtles)

No placental care

Shell parts in Testudinia

Dorsal: Plastron (underside of shell)

Ventral: Carapace (hard upper shell)

Crocodilia traits

Thick, non-overlapping scales

Laterally compressed tails


4 chambered heart

Differences in crocodilian snouts

Crocs: Narrow

Gator: Broad

Aves traits

Evolved flight


Convergent evolution

Hollow bones

4 chambered heart

Bird lung connected to anterior and posterior sacs

Bird breathing step 1

Inhalation 1: Air fills posterior sacs

Exhalation 1: Air moves to lung, new air in posterior

Bird breathing step 2

Inhalation 2: Air from lung moves to anterior sac

Exhalation 2: Air leaves anterior sac and moves to lung


Generate heat via metabolism and retain it viause of fur/hair (ex. Birds, mammals)


All other tetrapod animals in which temperature is comparable to ambient temperature

Temperature regulation increases...

Enzyme rates significantly

If cold...

Shivering response

Muscular activity produces heat

Vasoconstriction reduces heat loss

If hot...

Sweating uses heat to evaporate water

Vasolidation loses heat

How does body surface play an important role in thermoregulation?

Smaller body= a larger SA to volume ratio vs, large body

What do infants use to retain heat?

Infants use brown fat which has a higher amount of mitochondria

Mammary Gland

exocrine organ that produces nutrients for offspring

Increases maternal investment


Ducted gland releases secretory material into duct (salviary, sweat, etc.)


Ductless glands release secretory material into extracellular environment (bloodstream)

Monotreme traits

Platypus and 4 species of echidnia

Egg layers

Produce small eggs

Platypus traits

Beack has electro/mechno sensory structures used for foraging

Rear limbs contain venom glands (males only)


Pouched animals

Initially live bearing

Nourish embryos using placenta but born under developed

What happens after marsupial young are born?

After birth, offspring get in pouch (marsupium) or attach to mom and suckle to continue devlopment

Unique reproductive traits of Marsupials

Female: 2 uteri and 2 vagina with 3rd "psuedo" vagina

Male: 2 prong penis used only for copulation

Eutherian Mammal Traits

Placental viviparity using chorio-allontric placenta

Better developed embryos

Cons of eutherian placental mammals

Long gestation/Premature loss

Energetically expensive

Trends of eutherian mammal evolution

Amphibian lung- sac with folds

Reptile lung- complex with accessory air sacs

Mammalian lung- increased surface area by grape like clusters known as alveoli

Mammalisn circulation

Double pump system

4 chambered heart

Oxygenated blood

Primates trends

Opposable thumbs



Extensive parental care

Large brain to body size ratio

Color vision

Eyes face forward


Before monkeys

Lemurs, lorises

Small, arboreal


Human like

Old world monkeys: africa and asia

New world monkeys: central and south america

Lesser apes: Gibbons

Great apes (hominids): gorilla, orangutan, chimps, bonobo, humans

Great Apes

Hand walkers- orangutan

Knuckle walkers- gorilla, bonobos, chimps

Bipedalism- humans

Benefits of bipedalism

Frees up hands

greater mobility

greater sensitivity of hands

greater field of view

Types of Hominins

Gracitie Australopithecines

Robust Australopithecines

Early Homo sp.

Recent Homo sp.

Gracitie Australopithecines

3-4 ft in height


Large jaw and teeth

Robust Australopithecines

~3-1.5 mYA

Large sagittal crest that attaches to jaw muscles

Large jaw met an evolutionary dead end

Early Homo sp.

Taller, more narrow face

Smaller jaw and teeth

Brain case increases in size

Coincides with first appearance of stone tools

Recent Homo sp.

1 mYA to present

Longer limbs

More streamlined body

Narrowing of face

Increased cranial capacity

Major trends in primate evolution

Increased height/overall body size

Reduction in jaw/tooth size

Increased cranium and brain size

Out of Africa Hypothesis

Homo sapiens evolved in Africa and dispersed inmultiple waves

Evidence of interbreeding between Neanderthalmales and H. sapiens females

Large, rounder body- low surface area/vol ratio

Differences in SA/V ratio

High SA/V ratio= adaptation for dissipating heat

Low SA/V ratio= adaptation for conserving heat

Sunlight differences in evolved humans

Greater sunlight= more UV light= selectivepressure that favors dark skin

Lower sunlight= lower, UV light= selective pressurethat favors light skin

Cultural selection

Lactosetolerance evolved in adult humans due to cattle/use of milk