Introduction to the Animal Kingdom

Chapter 26

What is an Animal?

They share certain characteristics Heterotrophs Multicellular Eukaryotic Bodies contain tissues

Either invertebrates or vertebrates

Invertebrates

95% of all animals are here

These animals DO NOT have a backbone

Examples: Dust mites, giant squids, worms, insects, etc.

Vertebrates

Other 5% of the animals

HAVE a backbone

Examples: Fish, amphibians, reptiles birds and mammals

What animals do to survive

Animals carry out the following essential functions: Feeding Respiration Circulation Excretion Response Movement Reproduce

Feeding

Animals need to eat food Herbivores Carnivores Omnivores Detritivores Filter feeders Symbiotic relationship

Feeding

http://video.nationalgeographic.com/video/player/animals/bugs-animals/ants-and-termites/ant_caterpillarsymbiosis.html

Respiration

Take in oxygen and give off carbon dioxide

Some rely on diffusion through their skin

Other have complex tissue and organ systems

Circulation

Diffuse oxygen, waste, and nutrients through the skin

Or

Have circulatory systems

Excretion

Remove ammonia from cells and body

Ammonia has nitrogen; in large amounts it can kill an animal

Removes other metabolic wastes

Response

Response to environmental events by using specialized cells Nerve cells

Examples are: responses to light, sound, etc.

Movement

The ability to be motile

Have muscles that move supported by a skeletal system

In sedentary animals- muscles feed and pump water and other fluids through the body

Reproduction

Sexually

Asexually

Trends in Animal Evolution

Different phyla are related through a common evolutionary heritage

Cell specialization Internal body organization Bilateral body symmetryCephalization Body cavity

Cell Specialization

Blastopore formed from blastula Protosome Deuterostome

Cells form in 3 layers Endoderm- Inner most layer Mesoderm- Middle layer Ectoderm- Outer most layer

Body Symmetry

Radial Symmetry Body parts repeat around the center of the

body Example- Bike wheel

Bilateral Symmetry 2 equal halves from the plane of symmetry Example- Cray fish or Humans

Cephalization

Concentration of sense organs and never cells in the front of the body

Anterior end move forward

Body Cavity Formation

Allows for the formation of organs Suspended and protected Not pressed on by muscles Not twisted out of shape by movement Leaves room for growth and expansion

Body Cavity Formation

In other animals, the space contains fluids for: Circulation Feeding Excreting