CLEP CLEP Biology Animal Behavior and Reproduction 3

Question 1

Gastrulation during animal embryonic development produces:

Accepted Answer

The three primary germ layers: ectoderm, mesoderm, and endoderm

Answer

Gastrulation transforms the blastula into a gastrula through coordinated cell movements, establishing the three primary germ layers from which all tissues and organs develop.

Question 2

Neural crest cells, which migrate away from the developing neural tube, give rise to which structures?

Accepted Answer

Peripheral nervous system, facial bones, and adrenal medulla

Answer

Neural crest cells are multipotent migratory cells that form peripheral neurons, craniofacial skeletal structures, melanocytes, and the adrenal medulla, among other tissues.

Question 3

Embryonic induction refers to which developmental process?

Accepted Answer

One tissue group signaling to alter the developmental fate of adjacent cells

Answer

Induction occurs when signaling molecules secreted by one cell group change the gene expression and developmental trajectory of neighboring cells, as when the notochord induces neural tube formation.

Question 4

Complete metamorphosis (holometabolism) in insects follows which sequence of developmental stages?

Accepted Answer

Egg → larva → pupa → adult

Answer

Holometabolous insects like butterflies, beetles, and flies undergo four distinct stages — egg, larva, pupa, and adult — each adapted for specific ecological roles.

Question 5

Apoptosis during embryonic development is functionally important because it:

Accepted Answer

Eliminates unneeded or harmful cells to sculpt tissues and organs

Answer

Apoptosis (programmed cell death) sculpts tissues during development — for example, removing interdigital webbing to separate fingers and eliminating excess neurons that fail to connect properly.

CLEP Practice Test

CLEP Practice Test

CLEP CLEP Biology Animal Behavior and Reproduction 3