Pitts' Biology 120 Exam Number 2  Spring 2003

 

Place all answers on the attached answer sheet.  On multiple choice questions, select only one answer and write the letter that corresponds to your answer on the answer sheet.  If I have difficulty reading your answer, I must mark it wrong.  Class will not meet this Friday (21 February).

 

1.             Name one reason, out of several possibilities, that viruses are not considered to be alive.

 

2 & 3.      Name the two essential parts of all viruses.

 

4.             Viruses are typically measured in units called nanometers.  How many nanometers are present in 1 meter?

A. 100;  B. 1,000;  C. 1,000,000;  D. 1,000,000,000

 

5.             Which of the following best describes a virus that is in the free particle stage? 

A. virus is reproducing;  B. virus is being replicated by a host cell;  C. virus is not inside a host cell and is doing nothing;  D. none of the previous answers are correct since viruses cannot have a free particle stage

 

6.             A cell that has been lysed has:

A. taken in food;  B. increased in size due to gain of food or water;  C. gained additional receptors on its surface;  D. had its cell membrane broken open and the cell has been killed

 

7.             Polio virus will attack only nerve cells because nerve cells:

A. do not have any receptors to block the entry of viruses;  B. have the appropriate receptors for polio viruses;  C. cannot divide;  D. are the most numerous type of cell in the human body

 

8.             Which of the following is present in some viruses but never in bacteria?

A. flagella;  B. capsule;  C. reverse transcriptase;  D.  DNA (= deoxyribonucleic acid) 

 

9.             During the lysogenic cycle (= provirus stage), the viral nucleic acid attaches to, and becomes a part of, the host cell's _?_

A. ribosomes;  B. chromosome;  C. capsule;  D. flagellum

 

10.           Although the exact number of cells is not known, each of us has several body cells that contain viral nucleic acid that is in the provirus stage.  This situation:

A. is totally harmless, since the viruses never become active;  B. is a "time bomb" just waiting for the appropriate signal to activate it;  C. is usually beneficial to the host cell since the viruses reduce the number of harmful mutations;  D. almost always causes the host cell to mutate at a faster rate.

 

11.           The city of Martin, Tennessee has a cemetery (on Elm Street) which was used in the late 1800's for the burial of numerous persons who are known to have died from the disease named _?_

A. yellow fever;  B. kuru;  C. histoplasmosis;  D. polio;  E.  AIDS

 

12.           True or False  Because viruses are active only when they are inside a host cell and because the host cell's membranes and cytoplasm protect the viruses, antibiotics are not effective against viruses.

 

13.           Antibiotics are most effective against diseases caused by which of the following?

A. prions;  B. viruses;  C. bacteria;  D. fungi

 

14.           The virus (HIV, previously called HTLV-III) that causes AIDS was discovered approximately _?_ years ago.

A. 20;  B. 200;  C. 2,000;  D. none of these are correct since AIDS is not caused by a virus.

 

15.           What type of nucleic acid is present in retroviruses?

A. DNA;  B. RNA;  C. reverse transcriptase;  D. none of these can be correct since retroviruses do not contain any nucleic acid

 

16.            If Joe has a syndrome, Joe's condition is best described as:

A. a broken bone named the syndromus;  B. a disease of the immune system;  C. a group of disease causing organisms;  D. a group of symptoms or ailments

 

17.           A newly discovered medication breaks down reverse transcriptase.  Which of the following would be most affected by this new medicine?

A. prions;  B. retroviruses;  C. smallpox;  D. Gram negative bacteria

 

18.            Each HIV particle contains about 9,500 nucleotides that make up 7 to 10 genes; one of these genes has information for the manufacture of:

A. cell wall;  B. receptors;  C. capsule;  D. reverse transcriptase

 

19.            Each human cell contains approximately 40,000 genes.  In contrast to human cells, one HIV particle contains:

A. many more than 40,000 genes;  B. less than 100 genes;  C. no genes

 

20.           The latent period of HIV is defined as the time from exposure to HIV until a person shows definite symptoms of AIDS.  The average length of this latent period is:

A. ten minutes;  B. six months;  C. one year;  D. 10 years

 

21.            During the latent phase of HIV, the lytic cycle (also called the vegetative stage):

A. does not take place;  B. is occurring, but very slowly;  C. is occurring rapidly, but lost host cells are quickly replaced.

 

22.            The fact that HIV is _?_ during the latent period is bad news, because this means that mutations that enable the virus to evade medications can occur and be selected for.

A. active (in the vegetative stage or lytic cycle);  B. inactive (in the provirus or lysogenic cycle)

 

23.           Which of the following is an infectious agent that does not contain either DNA or RNA?

A. prion;  B. retrovirus;  C. Clostridium tetani;  D.  endospores of anthrax

 

24.           Yeasts, molds, and mushrooms are all members of which kingdom of living organisms?

A. Monera;  B. Animal;  C. Plant;  D. Fungi;  E. Protista

 

25            Name the kingdom for the organism that causes histoplasmosis.

 

26.           True or False  Histoplasmosis is transmitted by birds.

 

27.            From which of the following would a person most likely acquire histoplasmosis?

A. eating chicken that was processed by the Tyson company  B. playing with chickens;  C. breathing in spores from soil contaminated with chicken feces;  D. eating chicken that is not well cooked

 

28.           The primary way in which prions are transferred from one animal to another animal is by:

A. wind;  B. contaminated water;  C. physical contact;  D. eating food contaminated with muscle cells from an animal that has a prion disease;  E. eating food contaminated with nerve cells from an animal that died of a disease cause by a prion

 

29.            Kuru was transmitted from one person to another by the practice of:

A. eating the brains of deceased relatives;  B. drinking the blood of ancestors;  C. living in caves where one's ancestors had also lived  

 

30.           The best way to avoid acquiring a prion-caused disease is to:

A. get vaccination against the disease;  B. take strong antibiotics as soon as the disease is diagnosed;  C. eat no meat;  D. avoid all contact with birds

 

31.            How many people lived in Ireland before the potato famine of 1845-1852?

 

32.            How many people died due to food shortage in Ireland during 1845-1852?

 

33.           Name the kingdom for the organism that causes late blight in potatoes.

 

34.            Name the most successful (in a biological sense) type of organisms that now live on Planet Earth.

A. viruses;  B. bacteria;  C. plants;  D. humans

               

35.            Sketch the outline of a bacterium that is described as being a coccus.

 

36.           Which type of bacterium is more likely to cause a serious disease?

A. Gram +;  B. Gram -;  C. Gram + and Gram - are equally likely to cause disease

 

37.           Which of these has a protective capsule composed of lipopolysaccharides?

A. Gram + bacteria;  B. Gram - bacteria;  C. all bacteria

 

38. True or False  Most bacteria are harmful.

 

39.            Structures called _?_  best enable bacteria to survive periods of environmental stress.

A. nuclear membranes;  B. capsules;  C. cell walls;  D. endospores

 

40.            Alexander Fleming was the first microbiologist to:

A. see Penicillium;  B. observe that Penicillium frequently contaminated bacterial cultures grown in laboratories;  C. observe, demonstrate, and understand the fact that Penicillium inhibited the growth of some bacterial colonies;  D. prove that penicillin could kill all types bacteria.

 

41.           Anthrax is caused by:

A. bacteria;  B. virus;  C. prion;  D. fungus

 

42.            Humans usually acquire anthrax by :

A. coming in contact with endospores;  B. eating food containing actively growing anthrax organisms;  C. drinking water that contains anthrax;  D. sexual contact with a person who has anthrax 

 

43.            Which of the following routes of entry usually results in the most severe cases of anthrax?

A. digestive tract;  B. skin;  C. lungs;  D. all are equally deadly

 

44.           True or False   Fortunately, the late blight disease of potatoes has been conquered and is no longer a threat to potato crops.

 

45.            Proteins are the only material present in:

A. viruses;  B. bacteria;  C. fungi;  D. prions

 

46.            How can a person be infected with smallpox?

A. breathing air that contains the virus;  B. physical contact with someone who has smallpox;  C. physical contact with a non-living object (e.g., a blanket or clothing) that is contaminated with the smallpox virus;  D. mosquito bite;  E. all of these are correct;  F. Answers A, B, and C are correct, but D is not correct.

 

47.           What material was most commonly used for inoculation against smallpox before 1790?

A. active smallpox virus;  B. cowpox virus;  C. dead cells from a smallpox victim

 

48.            In what year did the last known case of smallpox occur?

 

49.            Since the discovery of the effectiveness of vaccination, what has been the greatest barrier to be elimination of smallpox as a human disease?

A. not enough smallpox virus;  B. not enough cowpox virus;  C. mutation of the virus;  D. public attitudes

 

50.           Name the first human disease to be controlled by intentionally administering a substance that would cause a person to be immune to that disease.

 

Back