Julie usually wakes up very tired each morning, but she wants to improve her ability to function during the day. she decides that she will go to sleep an hour earlier than usual from now on. the first night, she has trouble falling asleep, and when she wakes up tired, she abandons her plan. what is the best advice one could give julie about her plan and getting more sleep? a. scientists don’t know much about why we sleep. you can’t really do anything about it. b. it is usually better to go to sleep later, since you’ll be more tired. c. forming new habits takes time. stick with your plan. d. going to sleep earlier would never have . try something else.

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.

All but one describes an effect of aging on the digestive system. a) decreased acid secretion b) decreased elasticity of stomach c) capacity to resist damage decreases d) food remains in stomach for less time

Agene editing technology called crispr-cas9 uses cellular machinery to change the cell's genetic material. how might this technology be useful in treating diseases like cancer?