In a resting state, sodium (Na ) is at a higher concentration outside the cell and potassium (K ) is more concentrated inside the cell. During an action potential, the sodium levels inside the cell.

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.

This is the nitrogenous base only found in rna

The offspring of a black cat and a white cat is a gray cat, it has the genotype bw if a black cat mates with a gray cat the chance that the offspring is white will be what percent?