a group of mutations, known as mt-nd1
mt-nd1
, have been identified in mitochondrial dna
dna
. these mutations are associated with a number of debilitating diseases stemming from the production of nonfunctional proteins in the mitochondria.

which of the following cellular deficiencies would most likely be related to these mt-nd1
mt-nd1
mutations?

the cell is unable to synthesize most proteins required for normal cell functions.
0
a

the cell is unable to break down toxic materials and would accumulate large volumes of these materials.
0
b

the cell is able to synthesize proteins, but the proteins would not fold properly and would not contain the correct molecular tags for export from the cell.
0
c

the cell is unable to complete reactions related to electron transport and atp
atp
production

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.

What environmental cues and landmarks do the geese use to determine the timing and direction of their migration over the mountains? how do they find their way?

Which of these substances does not protect against invaders in the nonspecific immune response? a. saliva b. mucus c. tears d. urine