Classes of Vertebrates Flashcards

Study Notes

Vertebrates

Five major groups: fishes, amphibians, reptiles, birds, mammals, all with backbones.
Some scientists classify fish into three groups: cartilaginous, bony, and jawless.

Cold-Blooded vs. Warm-Blooded

Cold-blooded animals like reptiles, amphibians, and most fish adjust their body temperature based on their environment.
Warm-blooded mammals and birds maintain a constant body temperature regardless of external conditions.

Mammals (Mammalia)

Warm-blooded with skin structures producing hair or fur.
Unique feature: females produce milk for their young.
Hearts have four chambers.
Examples include cows, bears, humans, giraffes, bats, dogs, and lions.

Birds (Aves)

Also warm-blooded and possess hollow bones.
Unique feature: feathers are derived from the skin.
Hearts have four chambers.
Examples include blue jays, cardinals, hummingbirds, mockingbirds, ostriches, and penguins.

Reptiles (Reptilia)

Cold-blooded, often lay eggs, but not universally.
Unique feature: scaly skin, which is waterproof.
Hearts typically have three chambers.
Examples include snakes, alligators, lizards, chameleons, and turtles.

Amphibians (Amphibia)

Cold-blooded with porous skin and lay eggs without shells, typically in water.
Unique feature: slimy skin and undergo metamorphosis.
Hearts have three chambers.
Examples include frogs, salamanders, toads, caecilians, newts, and tadpoles.

Fish

The first organisms to possess backbones, equipped with scales and cold-blooded physiology.
Unique feature: gills for respiration throughout life.
Hearts have two chambers.
Examples include pufferfish, salmon, trout, smallmouth bass, striped bass, and sharks.

Blood Types

Oxygenated blood carries oxygen to cells, while deoxygenated blood carries little to no oxygen.
Capillaries are tiny blood vessels where the exchange of oxygen occurs.

Vertebrate Heart Anatomy

Fish Heart: Blood absorbs oxygen in gills with a two-chambered heart (aorta, capillaries, circulatory systems).
Amphibian Heart: A mixer of oxygenated and deoxygenated blood in a heart with a right and left atrium, ventricle, and systemic capillaries.
Reptile Heart: Similar mixing as amphibians, but with slightly more separation in the three-chambered heart.
Mammal and Bird Hearts: No mixing of oxygenated and deoxygenated blood, featuring a four-chambered heart.

Evolution of Vertebrates

The absence of mixed blood in mammals and birds supports the idea of advanced evolution.
Evolutionary lineage suggests fish transitioned to amphibians, with reptiles giving rise to birds and mammals, representing the most recent evolution.

Description

This quiz covers the five major classes of vertebrates, including fishes, amphibians, reptiles, birds, and mammals. Each card provides definitions and important characteristics of these groups, helping you understand the key differences between warm-blooded and cold-blooded animals.