Animal Diversity and the Evolution of Body Plans

These flashcards cover essential vocabulary and concepts related to animal diversity and body plans, summarizing the key features and classifications discussed in the lecture.

Heterotrophy

The ability of animals to obtain energy and organic molecules by ingesting other organisms.

Multicellularity

Organisms composed of many cells, allowing for complex body structures.

Radial Symmetry

Body parts arranged around a central axis, allowing division into equal halves through multiple planes.

Bilateral Symmetry

Body has right and left halves that are mirror images, with a single plane dividing it into equal halves.

Cephalization

The evolutionary development of a definitive brain area in bilaterally symmetrical animals.

Totipotent

Cells that can give rise to all other body cells; characteristic of zygotes.

Germ Layers

Layers of cells in the early embryo that develop into distinct tissues; include ectoderm, mesoderm, and endoderm.

Coelomate

Animals with a body cavity entirely within the mesoderm, allowing for the development of advanced organ systems.

Protostomes

Organisms that develop the mouth first from or near the blastopore during embryonic development.

Deuterostomes

Organisms where the anus develops first from the blastopore, with the mouth forming later.

Segmentation

The division of an animal's body into repetitive segments, allowing for redundant organ systems and increased flexibility.

Diversity of Habitat

The variety of environments in which animals live, including marine, freshwater, and terrestrial habitats.

Embryonic Development

The series of mitotic divisions that a zygote undergoes to form a developing organism.

Acoelomates

Animals that lack a body cavity.

Pseudocoelomates

Animals with a body cavity between the mesoderm and endoderm.

Functional Units of Tissues

Cells organized into structural and functional units within an organism, allowing for specialization.