1) What limits the resolving power of a light microscope?
A) the type of lens used to magnify the object under study
B) the shortest wavelength of light used to illuminate the specimen
C) the type of lens that focuses a beam of electrons through the specimen
D) the type of heavy metal or dye that is used to stain the specimen
E) the ratio of an object's image to its real size
Answer: B
Topic: Concept 6.1
Skill: Knowledge
2) When biologists wish to study the internal ultrastructure of cells, they most likely would use
A) a light microscope.
B) a scanning electron microscope.
C) a transmission electronic microscope.
D) A and C only
E) A, B, and C
Answer: C
Topic: Concept 6.1
Skill: Knowledge
3) The advantage of light microscopy over electron microscopy is that
A) light microscopy provides for higher magnification than electron microscopy.
B) light microscopy provides for higher resolving power than electron microscopy.
C) light microscopy allows one to view dynamic processes in living cells.
D) both A and B
E) both B and C
Answer: C
Topic: Concept 6.1
Skill: Knowledge
4) A primary objective of cell fractionation is to
A) view the structure of cell membranes.
B) identify the enzymes outside the organelles.
C) determine the size of various organelles.
D) separate the major organelles so their particular functions can be determined.
E) crack the cell wall so the cytoplasmic contents can be released.
Answer: D
Topic: Concept 6.1
Skill: Knowledge
5) In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet is
A) the relative solubility of the component.
B) the size and weight of the component.
C) the percentage of carbohydrates in the component.
D) the number of enzymes in the fraction.
E) the presence or absence of lipids in the component.
Answer: B
Topic: Concept 6.1
Skill: Knowledge
6) 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) ribosomes, nucleus, mitochondria
B) chloroplasts, ribosomes, vacuoles
C) nucleus, ribosomes, chloroplasts
D) vacuoles, ribosomes, nucleus
E) nucleus, mitochondria, ribosomes
Answer: E
Topic: Concept 6.1
Skill: Comprehension
7) Quantum dots are small (15-30 nm diameter), bright particles visible using light microscopy. If the dots can be specifically bound to individual proteins on a plasma membrane of a cell, which of the following correctly describes the advantage of using quantum dots in examining proteins?
A) The dots permit the position of the proteins to be determined more precisely.
B) The dots permit the average distance between the proteins to be determined more precisely.
C) The dots permit the size of the proteins to be determined more precisely.
D) The dots permit the motion of the proteins to be determined more precisely.
E) All of the above are correct.
Answer: D
Topic: Concept 6.1
Skill: Application
anyone know??? please hlep..thanks.. i only have 15 days so i don' twant to waste my time... sorry for being such an ass.
good luck!
