When a woman becomes pregnant from the fertilization of two separate ova by two separate sperm, these twins are called _________ twins:

The term race refers to a

A) ideological category. B) biological concept. C) cultural background. D) political category.

An ectothermic animal, if cold, will not be able to:

a. Regulate body temperature through the use of energy reserves b. Detect the presence of cold in the body c. Burrow in the ground to get warmer d. Crawl onto a rock to gain solar heat