how long do scientists estimate that the sea has been at its current level? A. 250 years B. 2,500 years C. 25,000 years D. 250,000 years

When neurons "fire," the first thing that happens is that sodium ions enter the cell. this does not require an input of energy. what can you infer from this?

Which level of ecological organization considers all of the populations of all species in a given area, but does not take in to account abiotic factors? Population Community Ecosystem Biome

In sound waves, the distance between compressions is called the wavelength. What is the distance between rarefactions called? speed frequency amplitude wavelength

Why are dominant alleles not necessarily more common than recessive alleles?

A researcher has sequenced a gene that has two alleles. she has a mixture of both alleles and clones them into e. coli using plasmids. she is interested in one particular allele that is correlated with a disease.

What most directly causes hypertension? lack of blood flow to the heart a weakening of a blood vessel wall excessive force of blood pumping injury to heart muscle

On the coast, strong sea breezes move cool air into the land to replace warm, rising air. This often causes A) cyclones. B) hurricanes. C) thunderstorms. D) tornadoes.

Which steroid hormone (s) would not be produced if you blocked the activity of p450scc?

Probably the main reason Africans, rather than Native Americans, became slaves in America was that? A. Indians passed North American diseases to the Europeans. B. Africans and Europeans shared immunities to Old World diseases. C.

Structures through which conduction impulses pass, in sequential order, causing the heart to contract: