Bio Ch. 34 Vocab

Vertebrates

A chordate animal with vertebrae, the series of bones that make up the backbone

Notochord

A longitudinal, flexible rod made of tightly packed mesodermal cells that runs along the anterior-posterior axis of a chordate in the dorsal part of the body

Pharyngeal Clefts

In chordate embryos, one of the grooves that separate a series of arches along the outer surface of the pharynx and may develop into [the other one]

Pharyngeal Slits

In chordate embryos, one of the slits that form from [the other one] and open into the pharynx, later developing into gill slits in many vertebrates

Lancelets

A member of the clade Cephalochordata, small blade-shaped marine chordates that lack a backbone

Gnathostomes

Member of one of the two main clades of vertebrates - have jaws and include sharks and rays, ray-finned fishes, coelocanths, lungfishes, amphibians, reptiles, birds, and mammals.

Chondrichthyes

Vertebrates with skeletons made mostly of cartilage, such as sharks and rays

Operculum

In aquatic Osteichthyans, a protective bony flap that covers and protects the gills

Swim Bladder

In aquatic ostiechthyans, an air sac that enables the animal to control its buoyancy in the water

Tetrapod

A vertebrate clade whose members have limbs with digits, including mammals, amphibians, and birds/other reptiles

Amniotes

A member of a clade of tetrapods named for a key derived character, the amniotic egg, which contains specialized membranes, including the fluid-filled amnion, which protects the embryo. Includes mammals as well as birds and other reptiles

Amniotic Egg

An egg that contains specialized membranes that function in protection, nourishment, and gas exchange. The amniotic egg was a major evolutionary innovation, allowing embryos to develop on land in a fluid-filled sac, thus reducing the dependence of tetrapods on water for reproduction

Amnion

A fluid-filled sac that surrounds, bathes, and cushions the embryo

Reptile

A member of a clade of amniotes that includes tuataras, lizards/snakes, turtles, crocodilians, and birds

Ectothermic

referring to organisms for which external sources provide most of the heat for tempurature regulation

Endothermic

Referring to organisms that are warmed by heat generated by their own metabolism, This heat usually maintains a relatively stable body temperature higher than that of the external environment

Diapsids

A member of an amniote clade distinguished by a pair of holes on each side of the skull. Include the lepidosaurs and archosaurs

Turtles

The only group of diapsids to have girdles inside of their ribcage

Lepidosaurs

A member of the reptilian group that includes squamates (lizards and snakes) and two species of New Zealand animals called tuataras

Archosaurs

A member of the reptilian group that includes living crocodilians, extinct pterosaurs (first to have flapping flight), and dinosaurs, including birds

Squamates

Lizards and snakes

Snakes

Descended from lizards with legs - some have retained vestigial pelvic and limb bones (why they’re included in the tetrapod group)

Mammals

A member of the clade Mammalia, amniotes that have hair mammary glands (glands that produce milk)

Mammary Glands

An exocrine gland that secretes milk for nourishing the young

Synapsids

A member of an amniote clade distinguished by a single hole on each side of the skull. Includes mammals

Monotremes

An egg-laying mammal, such as a platypus or echidna - have hair and produce milk, but lack nipples

Marsupials

A mammal, such as a koala, kangaroo, or opossum, whose young complete their embryonic development inside a maternal pouch

Eutherians

Placental mammals - mammals whose young complete their embryonic development within the uterus, joined to the mother by the placenta

Opposable Thumbs

A thumb that can touch the ventral surface (fingerprint side) of the fingertip of all four fingers of the same hand with its own ventral surface

Anthropoids

A member of a primate group made up of the monkeys and the apes (gibbons, orangutans, gorillas, chimpanzees, bonobos, and humans)