How do sex cells differ from other cells in an animal's body?

a. They are usually much larger.

b. They are always moving.

c. They do not need energy to perform their functions.

d. They have half the number of chromosomes.

How many times does the nucleus divide during meiosis?

What is a karyotype?

What is the average salinity of the world ocean? 0.02 percent 3.5 percent 22.9 percent 59.6 percent

O create hydrogen and oxygen from water, you would need to perform which type of reaction? a. synthesis b. decomposition c. double replacement d. single replacement

Every year, millions of acres of land are cleared by forest fires. Which of the following best describes a consequence of these catastrophic events? Carbon dioxide levels decrease rapidly in the areas near the fire.

A. Efficiency of public services is offered nearby. B. Use of mass transit instead of individual automobiles. C. Recycles underutilized and devastated properties. D. Human activities result in the development of urban heat islands. E.

What type of defense is the immune system? Specific or non-specific

Researchers have found that increasing global temperatures will cause methane (CH4), a greenhouse gas, to be emitted at increasing rates by microorganisms found in freshwater ecosystems.

Which structure is the site of nutrient and gas exchange between the mother and a growing fetus? A. placenta B. umbilical cord C. fallopian tube D. uterus

What kind of bond is formed when two atoms share a electron