Vertebrate Biology Quiz

Kingdom Animalia: Vertebrates

• Vertebrates are a group within the phylum Chordata, which also includes non-vertebrates like tunicates and lancelets.
• All chordates share four key characteristics: dorsal hollow nerve cord, notochord, pharyngeal pouches, and postanal tail.
• These embryonic structures develop into various adult structures: the nerve cord becomes the brain and spinal cord; the notochord becomes the vertebrae; pharyngeal pouches become gills (in fish) or various glands; the post anal tail becomes the tail or tailbone.

Types of Vertebrate Chordates

• There are eight classes of vertebrate chordates: Myxini (hagfishes), Cephalaspidomorphi (lampreys), Chondrichthyes (cartilaginous fishes), Osteichthyes (bony fishes), Amphibia (amphibians), Reptilia (reptiles), Aves (birds), and Mammalia (mammals).

Temperature Control

• Ectothermic ("cold-blooded") animals gain heat from their external environment; they have a low metabolic rate, burn fewer calories, and lack insulation. Examples include fish, amphibians, and reptiles.
• Endothermic ("warm-blooded") animals generate heat through metabolism; they have a high metabolic rate, burn many calories, and are insulated. Examples include birds and mammals.

Fish

• Fishes are aquatic vertebrates with gills and scales.
• Fish have a two-chambered heart.
• Types of fish egg development include:
  • Oviparous: eggs develop outside the female.
  • Ovoviviparous: eggs develop inside the female.
  • Viviparous: young are nourished directly by the mother's body.

Class Myxini (hagfish)

• Hagfish are jawless, have a circular mouth with short tentacles, possess a notochord in adulthood, and are mostly scavengers.
• They are characterized by being extremely slimy.

Class Cephalaspidomorphi (lampreys)

• Lampreys are jawless with a circular mouth lined with rasping teeth.
• They possess a notochord in adulthood and their larvae are filter feeders, while adults are parasites.

Class Chondrichthyes (cartilaginous fishes)

• Cartilaginous fishes have jaws and an endoskeleton of cartilage.
• They have tough scales.
• Examples include sharks, rays, and skates.

Class Osteichthyes (bony fishes)

• Bony fishes have jaws and an endoskeleton of bone.
• They have scales (some have lungs).
• Two groups: ray-finned fishes and lobe-finned fishes

Class Osteichthyes (1) Ray-Finned Fishes

• Ray-finned fishes have fins with slender bony spines.
• Examples include salmon, perch, sturgeon, tuna, and goldfish.

Class Osteichthyes (2) Lobe-Finned Fishes

• Lobe-finned fishes have fleshy fins with limb-bones.
• Examples include lungfish and coelacanths.

Class Amphibia (amphibians)

• Amphibians have smooth, moist, porous skin with glands.
• They breathe through gills in their larval stage and lungs and skin in their adult stage.
• They have a three-chambered heart.
• They are ectothermic.
• Their urogenital opening is a cloaca, and most are oviparous laying eggs without shells.
• Examples: salamanders, frogs, toads, and legless amphibians undergo metamorphosis during development from larva to adult.

Salamanders

• Salamanders are amphibians with tails in adulthood and typically have four legs.
• Some salamanders have gills in adulthood (e.g., mud puppy, axolotl).

Frogs & Toads

• Frogs and toads are amphibians that lack tails in adulthood.
• Aquatic larvae are known as tadpoles.
• Hind legs are adapted for jumping.
• Frogs generally have smooth skin, and longer legs; toads have bumpy skin and shorter legs.

Legless Amphibians

• Legless amphibians lack legs.
• These are terrestrial burrowers that live in the tropics.
• An example is the caecilian.

Class Reptilia (reptiles)

• Reptiles are adapted to dry land with dry scaly skin and claws.
• They have lungs.
• Most reptiles are ectothermic with a three or four-chambered heart.
• The urogenital opening is a cloaca.
• Their egg contains a leathery shell, yolk, allantois, chorion, and amnion.
• Reptiles include tuatara, lizards, snakes, crocodilians, and turtles/tortoises.

Amniotic Egg

• The amniotic egg is a shelled egg; the membrane contains the embryo, waste, nutrients (yolk sac), water (albumen), and gas exchange (chorion).

Tuatara

• The tuatara retains prehistoric reptile features, has no ears, primitive scales, jawbone teeth, and a "third eye" (pineal gland).
• There is only one species or type.

Snakes & Lizards

• Lizards typically have legs and snakes lack them.
• Examples include iguana, gecko, cobra, python, and boa.

Crocodilians

• Crocodilians have a four-chambered heart.
• Alligators and caimans live only in fresh water, and crocodiles can live in freshwater or saltwater.
• Examples include alligator, crocodile, and caiman.

Turtles & Tortoises

• Turtles have a bony shell with ribs and vertebrae fused to it.
• Turtles can swim and tortoises cannot.

Class Aves (birds)

• Birds have feathers: contour, down, and powder feathers.
• They have scales on their legs and feet.
• Their bones are hollow and lightweight for flight..
• They have well-developed lungs and air sacs.
• Birds are endothermic and have a four-chambered heart.
• The urogenital opening is a cloaca.
• Birds are oviparous.
• Examples: owl, eagle, duck, chicken, pigeon, penguin, sparrow, stork.

Respiratory System of Birds

• Birds have a unique respiratory system involving air sacs to allow for one-way airflow through their lungs.

Class Mammalia (mammals)

• Mammals have mammary glands that produce milk.
• They conserve body heat by insulation (fur/hair).
• Mammals are endothermic with lungs.
• The urogenital opening is usually a separate structure.
• The diaphragm divides the thoracic and abdominal cavities in the mammal.
• Mammals have a four-chambered heart and most mammals are viviparous with a placental connection to nourish their developing young.

Monotremes

• Monotremes are egg-laying mammals, possess a cloaca, and lay eggs.
• They produce milk from primitive nipple-like structures.
• Examples: duck-billed platypus, short-beaked echidna.

Marsupials

• Marsupials have a viviparous mode of reproduction, where the embryo uses up yolk in the uterus before crawling into a pouch (marsupium) to mature further.
• Examples include the opossum, kangaroo, and koala.

Placentals

• Placental mammals are viviparous, with young developing to term in the uterus.
• An embryo is nourished through the placenta.
• Orders: insectivores, bats, primates, edentates, lagomorphs, rodents, cetaceans, carnivores, elephants, sirenians, odd-toed ungulates, and even-toed ungulates.

Vertebrate Systems

• Major systems: digestive, circulatory, respiratory, and urogenital.

Digestive System

• Carnivores have short digestive tracts, while herbivores have long digestive tracts.

Circulatory System

• Fish have 2-chambered hearts, amphibians have 3, reptiles have 3 or 4, birds have 4, and mammals have 4.
• Single-loop circulatory systems occur in fishes, while double loops occur in more complex animals.

Respiratory System

• The evolutionary trend in lungs is an increasing surface area from amphibians to reptiles to mammals. Birds have lungs and air sacs for efficient breathing.

Urogenital System

• Kidneys are excretory structures in vertebrates.
• A cloaca is a urogenital opening present in amphibians, reptiles, birds, and some mammals (monotremes).

Nervous System - Brain

• Different vertebrates have brains with varying structural complexity, as reflected in the diagrams.

Human Brain

• The human brain is a complex organ with distinct lobes, structures, and substructures which are presented in a diagram.

Predation

• Predation is defined as when a predator kills and eats prey.
• Predators and prey have adaptations to increase success in their interactions.
• Some predation strategies are ambush, ballistic interception, pursuit, or lunge feeding.
• Predator-prey populations are often intertwined; as one population changes the other population often changes.

Predation Capture Strategies - Examples

• Amubush (surprise attack): like a cougar
• Ballistic interception (predicts the motion of prey to capture): a lizard quickly catching a fly.
• Pursuit (quick chase of prey): wolves chasing deer.
• Lunge Feeding (rapid movement to capture prey): catching fish, or other prey.

Test your knowledge on the digestive and circulatory systems of herbivores and other vertebrates. This quiz covers topics such as predator strategies and the excretory structures found in various vertebrates. Challenge yourself to see how much you know about vertebrate biology!