ANIMAL KINGDOM

ANIMALS

ANIMAL CHARACTERISTICS

- Eukaryotics- Multicellular- Lacking cell wall- Heterotrophs (ingest and digest)- Mobile or have mobility in at least one life stage- Sexual reproduction, produce an embryo

ANIMALS

CHARACTERISTICS USED TO CLASSIFY ANIMALS

1. Invertebrate or Vertebrate2. Levels of organization3. Number of body layers4. Symmetry and body plans5. Body cavity6. Segmentation7. Movement8. Reproduction

ANIMALS

1. INVERTEBRATE OR VERTEBRATE

INVERTEBRATE: no backbone, 95%

VERTEBRATE: internal skeleton and backbone, 5%

ANIMALS

2. LEVELS OF ORGANIZATION

- Differences in structure, tissues, organs and organ systems- All have cells- All have tissues (except sponges)

ANIMALS

3. NUMBER OF BODY LAYERS

- All animals have three cell layers (except sponges and phylum cnidaria-corals, hydras, jelly fish and sea anemones)- Layer 1 endoderm = inner layer: lungs, liver, pancreas, bladder,

stomach lining- Layer 2 mesoderm = middle layer: muscles, blood, kidneys,

reproductive organs- Layer 3 ectoderm = outer layer: skin, nerve tissue, sense organs

- All layers develop during early embryo growth- Layers help sort cells into arrangements for specialized tissues

and organs

ANIMALS

3. NUMBER OF BODY LAYERS

ANIMALS

4. SYMMETRY AND BODY PLANS

- Different arrangements of cells, tissues and organs leads to different body plans

a) Asymmetrical = irregular body shapeb) Radial Symmetry = divided along any plane parallel to body

axisExample: corals, jellyfish

c) Bilateral Symmetry = divided into two mirror halves only along one plane through the central axis

Example: worms, insects, vertebrates

ANIMALS

4. SYMMETRY AND BODY PLANS

ANIMALS

5. BODY CAVITY

- Coelom: fluid filled cavity that provides space for the development and suspension of organs and organ systems- Gives muscles a structures to brace against, allowing quick

movement and recovery- Allows increased complexity

- Coelomates: worms, molluscs, insects, vertebrates- Acoelomates: corals, jellyfish, flatworms

ANIMALS

5. BODY CAVITY

ANIMALS

6. SEGMENTATION

- Segmentation: the division of the body into repetitive sections

Advantages:- If a single segment is damaged, other segments can continue

to function properly- Increased mobility

ANIMALS

6. SEGMENTATION

ANIMALS

7. MOVEMENT

- Nerve and muscle tissue allow complex and fast movement

Sessile: stationary, live attached to one place; juvenile development allows for movement

Ex: sponges, sea anemones

ANIMALS

7. MOVEMENT

ANIMALS

8. REPRODUCTION

- Sexual: gametic- Zygote = diploid organism = gametes = fertilization = zygote…- 2 types of fertilization:

- External: gametes combine outside body, mostly aquatic- Ex: fish, amphibians

- Internal: gametes combine inside body- Ex: humans

- Asexual: typically asexual though sexual reproduction can occur during harsh conditions- Ex: aphids

ANIMALS

8. REPRODUCTION