Cell & Molecular Biology Karp Chapters 1-4 Test Exam Questions And Answers

Cell & Molecular Biology Karp
Chapters 1-4 Test Exam Questions
And Answers
If you were to argue that viruses are living organisms, what features of viral structure
and function might you use in your argument? - ANSWER- That viruses contain genetic
material; that they are capable of producing more of themselves, albeit only inside a
host cell; that they contain complex biological macromolecules; that they evolve. These
are all important criteria of living organisms.
Suppose you were a scientist living in the 1890s and were studying a disease of
tobacco crops that stunted the growth of the plants and mottled their leaves. You find
that the sap from a diseased plant, when added to a healthy plant, is capable of
transmitting the disease, to that plant.You examine the sap in the best light microscopes
of the period and see no evidence of bacteria. You force the sap through filters whose
pores are so small that they retard the passage of the smallest known bacteria, yet the
fluid that passes through the filters is still able to transmit the disease. Like Dimitri
Ivanovsky, who conducted these experiments more than a hundred years ago, you
would probably conclude that the infectious agent was an unknown type of unusually
small bacterium.What kinds of experiments might you perform today to test this
hypothesis? - ANSWER- You could examine the filtrate under the electron microscope
and determine whether the infectious agent was cellular, i.e., bacterial, or noncellular,
i.e., viral. You could try to culture the infective agent. If it was a bacterium, you should
be able to culture the agent in the absence of host cells, but not so if it were a virus. You
could determine the size of the genome (i.e., the RNA or DNA that constituted its
genetic material). If it was cellular, it would be expected to have a much larger genome
than if it was viral.
Prokaryotic cells can be distinguished from eukaryotic cells by the absence of:
a) a nucleus
b) DNA
c) a plasma membrane
d) All of these are absent. - ANSWER- A nucleus
Eukaryotic cells can be found in all of the following organisms EXCEPT:
a) animals.
b) bacteria.
c) plants.
d) fungi. - ANSWER- bacteria
Which of these is NOT a common feature of eukaryotic and prokaryotic cells?
a) Mechanisms for transcription and translation
b) Genetic information encoded in DNA
c) Construction of plasma membrane
d) Cytoplasmic organelles such as endoplasmic reticulum and Golgi complex. -
ANSWER- Cytoplasmic organelles such as endoplasmic reticulum and Golgi complex
All of the following are examples of prokaryotic cells EXCEPT:
a) viruses.
b) cyanobacteria.
c) bacteria.
d) mycoplasma. - ANSWER- viruses
Model organisms used by cell and molecular biologists include all of the following
EXCEPT:
a) mice.
b) bacteria.
c) nematodes.
d) orangutans. - ANSWER- orang