An Introduction To Animal Diversity

Front 1

There are exceptions to nearly every criterion for distinguishing an animal from other life forms. However, five criteria takes place

Back 1

1. Animals are multicellular, ingestive heterotrophs
2. Animal cells lack cell walls that provide structural support for plants and fungi
3. Animals have two unique types of cells: nerve cells for impulse conduction and muscle cells for movement.
4. Most animals reproduce sexually, with the diploid stage usually dominating the life cycle.

Front 2

Animals are multicellular, ingestive heterotrophs. Explain

Back 2

Animals take in performed organic molecules through ingestion, eating other organisms or organic material that is decomposing

Front 3

Animal cells lack cell walls that provide structural support for plants and fungi. Explain

Back 3

1.The multicellular bodies of animals are held together by extracellular structural proteins, especially collagen.
2.Animals have other unique types of intercellular junctions, including tight junctions, desmosomes, and gap junctions, which hold tissues together.
3.These junctions are also composed of structural proteins.

Front 4

Most animals reproduce sexually, with the diploid stage usually dominating the life cycle. Explain

Back 4

1. In most species, a small flagellated sperm fertilizes a larger, nonmotile egg.
2. The zygote undergoes cleavage, a succession of mitotic cell divisions, leading to the formation of a multicellular, hollow ball of cells called the blastula.
3. During gastrulation, part of the embryo folds inward, forming layers of embryonic tissues that will develop into adult body parts.
4. The resulting development stage is called a gastrula.