About how many years ago do scientists suggest that the earth cooled enough for water vapor to condense.

A) 20 millions years

B) 4.6 billion years

C) 4.4 billion years

D) 5.5 billion years

A chlorine atom that has 17 protons and 18 neutrons is called?

Which is not a type of passive transport

Which part of the ear receives vibrations directly from the eardrum? cochlea hammer stirrup anvil

What did watson and crick win due to their discovery of the structure of dna?

The founder effect can cause the loss of alleles. a. True b. False

Which sources do scientists use to reconstruct past climate conditions? Check all that apply. fossils frozen in glaciers daily temperatures pollen grains preserved in sediment running water tree rings

In beetles, the gene for color and the gene for pattern are located on the same chromosome and exhibit recombination.

Nucleic acids are composed of monomers called?

Cyclic amp (camp) stimulates one's metabolic rate. many supplement companies offer products claiming to increase the levels of this chemical within the body.

Injecting a person with a killed-bacteria vaccine can protect that individual from a disease because the proteins of the bacteria: A) remain in the body and live bacteria later prey on them instead of live tissue B) blind with receptors in the body,