Class Reptilia Lecture Notes

These flashcards cover the vocabulary and key concepts of Class Reptilia, including anatomy, reproduction, locomotion, and classification from the lecture notes.

Class Reptilia

True terrestrial vertebrates consisting of approximately $8000$ species.

Amniotic egg

A shelled egg (calcareous or leathery) containing an amnion, embryo, yolk sac, chorion, and allantois.

Jacobson’s organ

An olfactoric chamber connected to the tongue, also known as the Ruysch’s organ or vomeronasal organ.

Poikilothermic

Refers to reptiles' inability to regulate their body temperature internally, relying on external environmental heat.

Uric acid

The form in which reptiles excrete nitrogenous waste as part of water conservation adaptations.

Salt glands

Glands located near the nose or eyes of reptiles used for water conservation.

Occipital condyle

A single articulation point at the base of the reptile skull.

Order Testudines

The taxonomic order containing turtles.

Carapace

The top part of a turtle's shell, which includes fused vertebrae and ribs.

Plastron

The ventral or bottom portion of a turtle's shell.

Oviparous

A reproductive method where organisms lay eggs; characteristic of turtles.

Order Squamata

The largest reptile order, containing lizards and snakes, making up $95\%$ of all reptiles.

Kinetic skull

A jointed, movable skull typical of the order Squamata that allows for consuming large prey.

Sub-order Sauria

The taxonomic sub-order corresponding to lizards.

Sub-order Serpentes

The taxonomic sub-order corresponding to snakes, characterized by a limbless body and flexible skeleton.

Spectacle

A transparent membrane covering the eyes of snakes that replaces eyelids and prevents blinking.

Lateral undulation

A common S-shaped movement pattern used by snakes.

Concertina movement

A type of snake locomotion involving accordion-like extension and contraction.

Rectilinear movement

A movement where a snake moves forward in a straight line by contracting and stretching its body muscles.

Side-winding

A locomotive method where a snake throws its body forward in loops.

Pit organs

Heat-sensing structures found in nocturnal pit vipers that contain receptors packed with mitochondria.

Neurotoxic

A category of venom that targets the nervous system.

Hemotoxic

A category of venom that targets the blood and circulatory system.

Order Crocodilia

The order containing crocodiles and alligators, notable for having a $4$-chambered heart.

Thecodont dentition

A tooth arrangement where teeth are set into deep sockets; characteristic of Crocodilians.

Herpetology

The scientific study of reptiles and amphibians.

Synapsids

A lineage of amniotes with a single temporal opening, which led to modern mammals.

Diapsids

A lineage of amniotes with two temporal openings, including lizards, snakes, and crocodilians.

Anapsids

A lineage of amniotes characterized by having no temporal openings in the skull, traditionally including turtles.