BIOL 102 - The Animals

Flashcards covering key vocabulary and concepts from the Animal Biology lecture notes.

Kingdom Animalia

Multicellular, eukaryotic, heterotrophic organisms that are typically motile and reproduce sexually.

Choanoflagellate protists

The closest living ancestors to animals, these are solitary or colonial protists that share a cell type with sponges.

Hermaphrodites

Possessing both male and female gametangia in each individual; produce both male and female gametes through meiosis.

Gonorchism

Each individual represents one of the two genders; male and female gametangia in separate individuals.

Fertilization

Fusion of the gametes to produce a diploid zygote.

Budding

Unequal division of a parent body into two genetically identical individuals of unequal size.

Fragmentation

A piece of a parent body breaking away and becoming a second genetically identical individual.

Regeneration

Replacement of a lost body part.

Parthenogenesis

The development of an unfertilized egg into a new haploid individual.

Cleavage

Cell splitting allowing for the increase in cell number.

Morula

Solid ball of 16-64 cells.

Blastula

Hollow sphere of cells.

Gastrulation

The migration of cells through the blastopore to create germ layers.

Blastocoel

Hollow fluid-filled cavity in the blastula.

Blastopore

Opening on the blastula that becomes a mouth or anus for an animal.

Embryonic germ layers

The earliest tissues that eventually differentiate and give rise to all animal body parts.

Diploblastic animals

Animals that only produce 2 embryonic germ layers (ectoderm and endoderm).

Triploblastic animals

Animals that produce all 3 germ layers (ectoderm, mesoderm, and endoderm).

Ectoderm

Becomes the skin, hair, nails, and nervous system.

Mesoderm

Becomes the bone, cartilage, muscle, blood, connective tissue and cardiovascular system.

Endoderm

Becomes the organs of the digestive and respiratory systems.

Radial symmetry

A body that can be divided along multiple planes yielding two mirror images.

Bilateral symmetry

A body that can be divided along only one plane yielding two mirror images.

Cephalization

The presence of an observable head, where nervous tissue is concentrated in the anterior end of the body.

Acoelomate

Animals that lack a true body cavity; organs are embedded in tissue.

Pseudocoelomate

Animals that have a false or fake body cavity incompletely lined by mesoderm.

Coelomate

Animals that have a true body cavity completely lined by cells of the mesoderm germ layer.

Incomplete gut

A gut with only one opening that serves as both mouth and anus.

Complete gut

A gut with two openings present; mouth and anus are separate.

Segmentation

The division of an organism’s body into equal or unequal parts.

Protostome development

Cleavage is spiral and determinate; mouth develops from blastopore.

Deuterostome development

Cleavage is radial and indeterminate; anus develops from blastopore.

Invertebrates

Animals without backbones (no vertebrae or spinal column).