A weakened immune system may be caused by

an overproduction of lysozymes.

muscle disorders.

immunodeficiency disorders.

complement systems in the blood.

Prolactin is a hormone that:

When chickens with splashed white feathers are crossed with black-feathered birds, their offspring are all slate blue (Blue Andalusian).

Which choice best describes the phosphorus cycle?

How do cells in a multicellular organism become specialized? A. Genetic recombination determines which genes are located in each cell within a multicellular organism. B.

The trachea, bronchi, bronchioles and alveoli all make up the

If there is a possibility of four different genotypes in the offspring that result from a dominant-recessive inheritance, and if the couple has four children, would they definitely have children with one expressing each genotype?

The ovaries are located in the ___ cavity.

Transport of materials into a cell against a concentration gradient, from low to high, requires A) water. B) energy. Eliminate C) osmosis. D) a passageway.

As ocean water in a tide pool warms and evaporates, the remaining water becomes a. cooler. b. saltier. c. calmer. d. darker.

Drake is comparing time people spend playing games on Xbox versus Playstation. In his study, individuals ages 10 - 15 are given Xbox's and individuals ages 16 - 25 are given Playstations.