Which option describes adaptation? Select one:
1)Over time, populations gain traits that make them
more suited for the environment.
2)Only the strongest
individuals in a population are likely to survive.
3)Parents pass their genes to their offspring.
4)If there are enough resources, the population will
grow.

Explain two reasons you think it is important for scientists to search for new ways to treat cancer

Mouse liver cells were homogenized and the homogenate subjected to equilibrium density-gradient centrifugation with sucrose gradients. fractions obtained from these gradients were assayed for marker molecules (i.e., molecules that are limited to specific organelles). the results of these assays are shown in the figure. the marker molecules have the following functions: cytochrome oxidase is an enzyme involved in the process by which atp is formed in the complete aerobic degradation of glucose or fatty acids; ribosomal rna forms part of the protein-synthesizing ribosomes; catalase catalyzes decomposition of hydrogen peroxide; acid phosphatase hydrolysis monophosphoric esters at acid ph; cytidylyltransferase is involved in phospholipid biosynthesis; and amino acid permease aids in transport of amino acids across membranes. a) name the marker molecule and give the number of the fraction that is most enriched for each of the following cell components: lysosomes; peroxisomes; mitochondria; plasma membrane; rough endoplasmic reticulum; smooth endoplasmic reticulum.

Q: a: in sexually reproducing animals, once fertilization of the egg takes place, the exists as a single cell until cell division begins