ZOO 145 LAB Exer 4 Quiz

• ectothermic - rely on environmental heat to regulate body temperature

• keratinized skin - prevents water loss

• amniotes - development in a fluid-filled sac

• specialized skeletal features

• some have true claws

General features/characteristics of reptiles

Ectothermy

reptiles rely on the external environment (sunlight, warm ground, air) to modify blood flow and regulate body temperature. what is this called?

less energy expenditure

reptiles have lower food requirements =

90%

reptiles require up to (..) less food than same-sized endotherms

• Oberhaütchen layer

• beta-keratin layer

• meso layer

• alpha-keratin layer

layers of skin that are sloughed in reptiles when the new sequence of the same layers is ready to take their place

true claws

• curved or pointed appendages made of keratin

• found at the end of toes or fingers

amniotes

prevents the egg from drying out

• mammals - one foramen/opening in the skull

• turtles - lacks foramen/opening in the skull

• lizards, snakes, and crocodiles - two foramen/opening in the skull

differences between skulls of mammals, turtles, and lizards, snakes, and crocodiles

kinetic joints

Reptiles have flexible, (…) in their skulls, allowing them to move

parts of their upper jaw independently to swallow large prey

• laterally

• beneath

• Limbs extending (..) from the girdle in modern reptiles

• Limbs attached directly (…) the girdle in mammals and dinosaurs

• Sexual Dimorphism and Dichromatism

• Territoriality

• Courtship

• Mating

• Parity

• Parthenogenesis

life history of reptiles

Sexual Dimorphism and Dichromatism

• when males and females exhibit different body shapes or proportions

• when adult males possess adornments such as crests, casques, or horns

head and casque sizes

male and female Veiled Chameleons (Chamaeleo calyptratus) can be distinguished by the differences in their?

Malagasy vinesnake

this species exhibiting sexual dimorphism (female above, male below)

Territoriality

• drives sexual selection by ensuring dominant males secure exclusive access to mates and premium environmental resources

• highly prevalent during the breeding season

Courtship

• series of ritualized behavioral sequences and sensory signals

• attract mates

• reduce aggression

• ensure internal fertilization between the correct species

why is courtship used?

coitus

reproduction through internal fertilization

• turtles and crocodilians

• snakes and lizards

in mating, males have either a single penis (…) or paired hemipenes (…)

• oviparity

• viviparity

• ovoviviparity

3 types of parity

oviparity

development inside eggs (crocodiles and turtles)

viviparity

direct maternal transfer of nutrients (squamates)

ovoviviparity

development inside eggs that stay inside the mother’s body until hatching (squamates)

Parthenogenesis

• reproduction without the involvement of a male

• production of all-female populations that are genetic clones or near-clones of the mother

Aspidoscelis uniparens (parthogenetic)

Aspidoscelis tigris (sexual)

example of species exhibiting parthenogenesis

• arboreal

• semi-aquatic

• terrestrial

• aquatic

• fossorial

body forms of reptiles

label the parts

• rostral

• internasal

• prefrontal

• nasal

• loreal

• preoculars

• supraocular

• frontal

• postoculars

• subocular

• anterior temporal

• temporolabial

• posterior temporal

• parietal

• supralabial

• mental

• infralabial

scalation in snakes

• flexible and has a lower jaw that is not fused at the chin

• homogenous with simple recurved hooks

A snake’s skull is (…) allowing for considerable movement in all planes. The teeth are (…)

centrally arranged

In Lizard Anatomy, amphisbaenid skull illustrating the unique (…) tooth in the upper jaw

label the parts

scutes (carapace = top, plastron = bottom)

what covers a typical hard-shelled turtle

label the parts

label the parts in crocodylian anatomy (dorsal view)

label the parts in crocodylian anatomy (ventral view)

• body form

• body covering

• scale patterns

• dentition

• limb condition

qualitative features of reptiles

• scutes

• scales

• osteoderms

types of body covering

scutes

• body covering that has bony external plates

• formed on the dermis

• common in crocodiles and turtles

scales

• body covering that has rigid external plates

• formed on the epidermis

• common in snakes and lizards

osteoderms

• body covering that has hard bony plates or scales

• embedded within the dermis

• common in crocodiles, turtles, and lizards

• smooth transverse dorsal scales

• smooth oblique dorsal scales

• keeled dorsal scales

• tuberculate dorsal scales

types of scale patterns

• thecodont

• pleurodont

• acrodont

types of dentition in reptiles

thecodont

• placed in sockets inside the jaw bone

• crocodiles and snakes

pleurodont

• anchored on the inside of the jaw bone

• lizards

acrodont

• superficially attached to the jaw bone

• lizards

• opisthoglyphous - rear-fanged

• proteroglyphous - front-fanged

• solenoglyphous - hinge-fanged

fang types

• quadrupedal

• limbless

• reduced

types of limb condition

• columnar

• webbed

• flippers

types of limb condition

• pit organs

• pineal eyes

• y-shaped tongues

• tympanum

types of sense organs

• toe pads

• femoral pores

• crests

• frills

• dewlap

• fin

• toe fans

• fringes

other features in reptiles