Which substance do we consider to be the elementary unit of life?

A. DNA

B. protein

C. red blood cells

D. white blood cells

E. chromosomes

How does the function of melanin explain not only the variety of skin colors but susceptibility to skin cancer?

DNA expresses the genetic code in the arrangement of that code determines the characteristics of different in diverse organisms. Which of the following statements does not support the universality of DNA?

Which is most likely a vestigial structure? A. An ape's thumb B. A dolphin's flipper C. A whale's pelvis D. A rabbit's fluffy tail

The type of rock that has formed from seedements is called

What kind of cells does meiosis occur in

Ape species began to dwindle during the Miocene, leaving only a few remaining: a situation that exists up to the present. It is thought that the number of ape species reduced at that time because

Jon is in a car accident and severs an artery in his leg. He loses a significant amount of blood and experiences a drop in blood pressure. Explain how his body senses these changes, and how it will respond in an attempt to maintain homeostasis.

a scientist is conducting an investigation that involves water, silver corbon dioxide, and oxygen gas. Which group of statement best describes all of the materials he is using in the investigation?

The question below refers to the selection "taste-the final frontier." hydroponic plants are grown - a. on mars. b. without air. c. in water. d. in soil.

The movement of hot and cold air between land and sea creates what? a. Sea breeze b. Solar energy c. Trade winds d. Coriolis effect