How often does an el niño event occur?

a. about every other year

b. every 10 years

c. about every 2 to 3 years

d. about every 3 to 7 years

Researchers can manipulate the genes of a mouse so that a single gene in a single tissue either produces an inactive protein (a knockout mouse) or produces a protein that is always (constitutively) active.

A group of atoms held together by chemical bonds in a stable association is called?

What role does brownian motion play in diffusion and osmosis?

Which of the following bacteria does NOT belong with the others? A) Halobacterium B) Halococcus C) Methanobacterium D) Staphylococcus E) Sulfolobus

Skeletal myocytes and hepatocytes both store glycogen, but for different purposes. Myocytes synthesize glycogen when blood sugar is high and break it down when they need additional glucose to fuel their activity.

The biosphere is best described as the regions of Earth that support a. plant life b. animal life c. all life d. human life

A brown fruit fly was crossed with a black fruit fly as shown below. What is the probability of a resulting offspring being black? A. 100% B. 75% C. 25% D. 50%

What evidence do scientists have of the Silurian period?

All of the energy that drives Earth's rock cycle comes from

Which of the following is most clearly a benefit of genetic engineering? A. unpredictable genetic changes in a cow modified to have fewer fat cells B. production of human insulin through genetic modification of bacterial genes C.