A phospholipid is a common type of lipid molecule that is hydrophilic at one end and hydrophobic at the other. Explain how this structural characteristic of a phospholipid contributes to the formation of plasma membranes.

Which of the following must happen before the cell can go through mitosis? A. The cytoplasm must divide. B. The cell must copy its DNA. C. The spindle fibers must break down. D. The sister chromatids must separate.

Which animal has the most expensive mode of locomotion?

What are two ways scientists can describe the quality of measurements?

Which is not part of Darwin's theory of natural selection? A - Some organisms are better suited to their environment. B - Some genes are better than other genes. C - Traits vary among members of a population.

A roan cow (RW) is crossed with another roan cow (RW), what fraction of the offspring will be white (WW) ?

What is the most important part of the DNA molecule?

One function of the human excretory system is: 1. making materials that the body cells need 2. removing excess heat energy from the body 3. moving substances to and from body cells 4. controlling the body's responses to stimuli

Why did you need to heat the water when making salt water?

Sodium potassium pump

Arid and semiarid lands are prone to desertification because c. The precipitation cannot meet the growing demand for water or d. 10 per event of productivity is lost to erosion.