Which of the following best explains why a variety of monomers are needed to produce the complex molecules necessary for life? a. different monomers contain different kinds of atoms needed to produce different end products. b. all monomers contain the same kinds of atoms, but their unique structures result in different end products. c. different monomers contain different amounts of energy needed to initiate product formation. d. all complex molecules are formed from nucleotides, but other kinds of monomers are needed to produce energy.

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.

Complete the statements to identify the first two steps of meiosis i. (1 ) the first and longest step of meiosis i is called i. (2)the second step of meiosis i is called i.

The image below shows a common blood pressure gauge. what does this device do? a. measures the level of oxygen present in the blood b. measures the pressure of blood when the lungs expand and compress c. measures the electrical activity of the heart d. measures the pressure of blood when the heart contracts and relaxes