During meselson and stahl’s experiment, e. coli was grown on heavy nitrogen for what purpose?
a. so each generation of dna would have a different weight to distinguish them by.
b. so each generation of protein would have a different weight to distinguish them by.
c. to determine how the bacteria functioned with a heavier element.
d. to see how the heavy nitrogen affected their dna.

Which one of these is a involving in both sexual and asexual reproduction

Which type of neuroglia is found outside of the brain?

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.