Practice exam Bio 121 Essay

Submitted By XhoiTasho1
Words: 2670
Pages: 11

Bio 121 Exam 2 Fall 2010


1) The advantage of light microscopy over electron microscopy is that
A) light microscopy allows one to view dynamic processes in living cells.
B) light microscopy provides for higher magnification than electron microscopy.
C) light microscopy provides for higher resolving power than electron microscopy. D) A and B
E) B and C
2) Which of the following correctly lists the order in which cellular components will be found in the pellet when homogenized cells are treated with increasingly rapid spins in a centrifuge?
A) nucleus, mitochondria, ribosomes
B) ribosomes, nucleus, mitochondria
C) nucleus, ribosomes, chloroplasts
D) vacuoles, ribosomes, nucleus
E) chloroplasts, ribosomes, vacuoles
3) If a modern electron microscope (TEM) can resolve biological images to the nanometer level, as opposed to the best light microscope, this is due to which of the following? A) Contrast is enhanced by staining with atoms of heavy metal.
B) The focal length of the electron microscope is significantly longer.
C) Electron beams have much shorter wavelengths than visible light.
D) The electron microscope has much greater ratio of image size to real size.
E) The electron microscope cannot image whole cells at one time.
4) Why is it important to know what microscopy method was used to prepare the images you wish to study?
A) so that you can interpret the correct biochemical process that is occurring
B) so that you can make a judgment about the likelihood of artifacts having been introduced in the preparation
C) so that you can decide whether the image is actually of the size described
D) so that you can know whether to view the image in color or not
E) so that you can judge whether the images you are seeing are of cells or of organelles 5) All of the following are part of a prokaryotic cell except
A) an endoplasmic reticulum.
C) ribosomes.
D) a plasma membrane.
E) a cell wall.
6) Which of the following is a major cause of the size limits for certain types of cells?
A) the evolution of eukaryotes after the evolution of prokaryotes
B) the difference in plasma membranes between prokaryotes and eukaryotes
C) the evolution of larger cells after the evolution of smaller cells
D) the observation that longer cells usually have greater cell volume
E) the need for a surface area of sufficient area to allow the cell's function

7) Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
A) steroids
B) lipids
C) starches
D) proteins
E) glucose
8) Recent evidence shows that individual chromosomes occupy fairly defined territories within the nucleus. Given the structure and location of the following parts of the nucleus, which would be more probably involved in chromosome location?
A) the nuclear lamina
B) the nucleolus
C) nuclear pores
D) the outer lipid bilayer
E) the nuclear matrix
9) Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?
A) contractile vacuole
B) ribosome
C) mitochondrion
D) lysosome
E) smooth endoplasmic reticulum
10) Which structure is the site of the synthesis of proteins that may be exported from the cell? A) tight junctions
B) rough ER
C) plasmodesmata
D) lysosomes
E) Golgi vesicles
11) In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization? A) central vacuole
B) chloroplast
C) peroxisome
D) glyoxysome
E) lysosome
12) Which of the following statements correctly describes some aspect of protein disposal from prokaryotic cells?
A) Prokaryotes contain large pores in their plasma membrane that permit the movement of proteins out of the cell.
B) In prokaryotes, the ribosomes that are used for the synthesis of secreted proteins are located