Chordates & Vertebrates

Flashcards related to Chordates and Vertebrates

Notochord

A flexible dorsal rod in chordates that works with muscles for locomotion, present in embryos.

Dorsal (hollow nerve cord)

A tube in chordates that forms from a fold of ectoderm dorsal to the notochord.

Pharyngeal slits/clefts

Structures in chordates, ancestrally used for filter-feeding and gas exchange.

Muscular, post-anal tail

A tail in chordates with multiple muscle segments used for undulating locomotion.

Endostyle/Thyroid

Ciliated groove in chordates.

Cephalochordata: Lancelets

Chordates that possess all key chordate features in the adult stage and filter feed.

Urochordata: Tunicates

Chordates with a sessile adult form that suspension-feeds using pharyngeal slits; larva have chordate features.

Vertebrae

Cartilage and/or bone structures that enclose the spinal cord in vertebrates.

Cranium

Skull of cartilage or bone that holds the brain in vertebrates.

Gnathostomes

Vertebrates with hinged jaws derived from gill slit supports.

Lateral line system

A system in aquatic gnathostomes to detect pressure waves from prey and enemies.

Osmoregulation

The process by which gnathostomes maintains internal osmotic pressure at homeostasis.

Chondrichthyes

Cartilaginous fish with a skeleton of cartilage.

Osteichthyes

Bony fish that possess lungs or lung-derivatives.

Actinopterygii

Ray-finned fishes which possess thin fins supported by long, flexible rays.

Sarcopterygii

Lobe-finned fish with pelvic and pectoral fins supported by bones and muscles.

Tetrapods

Vertebrates with 4 limbs, wrists, digits, a pelvic girdle fused to the backbone and a neck

Class Amphibia

Basal extant tetrapod group with thin, moist skin that facilitates gas exchange.

Amniotic egg

An egg with specialized membranes that protect the embryo and reduce water loss, allowing reproduction away from water.

Ectothermic

An animal that uses the environment to warm its body.

Endothermic

An animal that warms its body with a high metabolic rate.

Amniote Phylogeny

Extant nonbird reptiles share many ancestral features such as scaly skin without feathers or fur and low metabolic rates.

Turtles

Amniotes with upper and lower body shells fused to ribs and vertebrae and keratin beak.

Lepidosaurs: Tuataras

Ancient lizard-like reptile with a light-sensitive pineal gland.

Lepidosaurs: Squamates

Lizards and snakes.

Archosaurs: Crocodilians

Semi-aquatic predators with both dinosaur and bird-like features.

Archosaurs: Birds

Diverged from a group of bipedal, feathered dinosaurs.

Mammals

Amniotes with mammary glands, sweat glands, and hair or fur.

Monotremes

Egg-laying mammals.

Marsupials

Mammals with a maternal pouch.

Eutherians

Placental mammals.

Primates

Mammals with hands and feet adapted to grasp, flat nails, and large brains.

Anthropoids

Monkeys, apes, and humans.

Homo sapiens

Characterized by bipedal locomotion, large brain, reduced jaws and canine teeth, language, and complex tools

Melanin

Pigment produced by melanocytes in the epidermis.

Eumelanin

Blackish brown pigment.

Pheomelanin

Reddish, yellow pigment.

Folate

B vitamin essential nutrient.

Vitamin D

Fat-soluble vitamin that maintains a healthy immune system and builds healthy bones and teeth.