Answer the questions and label the drawing below. A. ribosome
B. mitochondria
C. cell membrane
D. nucleolus
E. nucleus
F. vacuole
G. Golgi body
H. lysosome
I. cytoskeleton
J. cytoplasm
K. endoplasmic
reticulum
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
where proteins are made in the cells; the dots
provides strength and shape to the cell; network of protein fibers
control center of the cell; contains DNA
surrounds the internal cell parts; controls the passage of materials in and out
vesicle that contains substances that break down materials
produces energy
composed of protein and RNA; involved in ribosome production
vesicle that provides storage of water and other materials
packages and transports proteins from the ER to other parts of the cell
ER; passageways that transport proteins within the cell
everything inside of the cell membrane except for the nucleus

Which of the following is a cost of urbanization? a-cities can provide a high standard of living. b-cities are hubs of entertainment and education. c-paving over land changes the environment. d-job opportunities are greater in urban centers.

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.

Which of the following explains why a tree is often used as a model to represent the principle of common descent