Animal Characteristics and Development

Flashcards covering animal characteristics, essential functions, symmetry, and early development

Animal

A member of the kingdom animalia, multicellular, eukaryotic cells-lack cell wall, heterotrophs- their carbon source is organic molecules (they eat other living things)

Invertebrate

Animals that do not have a backbone - 95% of all animals

Vertebrate

An animal that does have backbone -5% of all animals (fish, amphibians, reptiles, birds and mammals)

Respiration

All animals respire meaning they take in oxygen and give off carbon dioxide, some animals can diffuse these gasses through their skin, but most animals have evolved complex tissue and organ systems for respiration

Feeding

Most animals must ingest (eat) food. Carnivores, herbivores, and omnivores. As well as detritivores - that feed on decaying plant and animal material and filter feeders that strain tiny floating organisms from the water

Movement

Most animals have muscles or muscle like tissue that generate force by becoming shorter. Even for animals that do not move from location to location, muscles help feed and pump water and fluids throughout their body

Circulation

Larger animals have some kind of circulatory system to move materials around within their bodies. Small animals that only have a few cell layers may be able to get away with diffusing things like oxygen and nutrients throughout their body

Excretion

Most animals have excretory systems that allow them to get rid of ammonia and other toxic waste products from cells.

Response

Animals have specialized cells called nerve cells that allow them to respond to their environment (sound, light etc).

Reproduction

Most animals can reproduce sexually helping create and maintain genetic diversity in populations. Some invertebrates can also reproduce asexually helping them increase their numbers rapidly

Radial symmetry

A Symmetry in which any number of imaginary planes can be drawn through the center, each dividing the body into equal halves. However you divide the body as long as the division goes through the center, the two resulting sides will be symmetrical) ex: bike wheel

Bilateral symmetry

Only a one plane can divide the body into two equal halves (crayfish) and us humans

Cephalization

A concentration of sense organs and nerve cells at the front end of the body

Body cavity

The body cavity is a fluid filled space that lies between the digestive tract and the body wall. It is important because it provides a space in which internal organs can be suspended so that they are not pressed on by muscles or twisted out of shape by body movements. They also allow organs to grow and expand

Endoderm

The innermost layer, and becomes the lining of the digestive tract and much fo the respiratory system

Mesoderm

Of middle layer becomes the muscle system, circulatory system, reproductive system and excretory organs

Ectoderm

Gives rise to sense organs, nerves and the outer layer of skin

Blastula

A hollow ball of cells.

Protostome

If the blastopore develops into the mouth first the animal

Deuterostome

If the blastopore develops into the anus first the animal