BIOL 1442 Ch 29 Reptiles

Reptiles are distinguished from amphibians by

terrestrially adapted egg

Reptilian eggs have ( ) extraembryonic membranes:

4; yolk sac, amnion, chorion, and allantois

An ( ) embryo is enclosed in the amnion

amniote

The shells of nonavian reptile eggs are

leathery and require a moist environment

The ( ) is the key characteristic of all amniotes

amniotic egg

Yolk sac

blood vessels in ( ) transport yolk nutrients to the circulatory system of the embryo

Chorion

facilitates exchange of oxygen and carbon dioxide

allantois

stores nitrogenous wastes; facilitates respiration

amnion

protects embryo from mechanical shock; supports hydration

Early amniotes diverged into

synapsids and sauropsids

Syanpsids include

theraspids

Sauropsids were divided into

anapsids and diapsids

The key difference between synapsids, anapsids, and diapsids is

the number of fenestrae

Anapsids have ( ) temporal fenestrae

no

Synapsids have ( ) temporal fenestrae

one

Diapsids have ( ) temporal fenestrae

two

Diapsids diverged into two groups:

Archosauromorpha and Lepidosauromorpha

Lepidosaurs include

modern lizards, snakes, and tuataras

Archosaurs include

modern crocodiles and alligators, ichthyosaurs, pterosaurs, dinosaurs, and birds

Reptiles are

tetrapods (or descended from tetrapods)

Reptiles reproduce

sexually with internal fertilization

A key adaption of reptiles is the development of

scaly skin, which reduced water lost from the skin

Reptiles cannot use ( ) for respiration

their skin

Most reptiles are

ectotherms

Reptiles have ( ) to help regulate body temperature

behavioral adaptations

In cold weather, some reptiles brumate, which refers to

a state similar to hibernation where the animal becomes less active and can go for long periods without eating

Reptiles originated

approximately 300 million years ago during the Carboniferous period

Pterosaurs are distinct from

true dinosaurs

Dinosaurs include

Saurischia and Ornithischia

Saurischia are

lizard-hipped dinosaurs with a simple, three-pronged pelvis

Ornithischia are

bird-hipped dinosaurs with a pelvis superficially similar to birds

Ornithischia were all

herbivores

Quetzalcoatlus northropi

pterosaur, may be largest flying animal that ever evolved

Pterosaurs have ( ) skeletons with ( ) a bone

ultralight; pteroid

Dinosaurs dominated the ( ) Era

Mesozoic

Class Reptilia has four living clades:

Crocodilia, Sphenodontia, Squamata, and Testudines

Crocodiles are ( ) runners

short distance

Crocodile habitats include

Africa, South America, Southern Florida, Asia, and Australia; freshwater, saltwater, and brackish

Sphenodontia are

Tuataras; Sphenodon punctatus and Sphenodon guntheri

Sphenodontia are found

in New Zealand

Tuataras have

a primitive diapsid skull with biconcave vertebrae, no external ears, and a third (parietal) eye

Squamata include

lizards and snakes

Lizards differ from snakes by having

four limbs

Some lizards can change their skin color by

redistributingg pigment within chromatophores in their skins

Both lizards and snakes use their tongues to

sample the environment, using Jacobson’s organ (pit in roof of mouth) to evaluate the sample

The only venomous lizards are

Gila monster and beaded lizard

An snakes are legless except

boids

Most snakes only have a ( ) functional lung

single

Most snakes have a ( ) skull including

flexible; eight rotational joints

Snake eyes are protected by

a transparent scale

Snakes have no external or middle ear, but

their inner ears are sensitive to ground vibrations

Testudines include

turtles, terrapins, and tortoises

Testudines are characterized by

a bony or cartilaginous shell

The dorsal shell

is called the carapace and includes the backbone and ribs

The ventral shell

is called the plastron

Both shells in testudines are covered with

keratinous plates called scutes

The two living groups of turtles are

Pleurodira and Cryptodira

Pleurodira are characterized by

horizontal neck retraction curve

Cryptodira are characterized by

vertical S-curve neck retraction

All turtles are

oviparous