Review for Chapter 7 Test
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
____1.Why are viruses like parasites?
a. / They harm the cells they enter.b. / They multiply.
c. / They use their own energy to develop.
d. / They make their own food.
____2.A virus’s proteins are important because they
a. / contain genetic material.b. / make new virus particles.
c. / provide energy for the virus.
d. / help the virus attach to its host.
____3.What characteristic of viruses makes them useful in gene therapy?
a. / their ability to enter cellsb. / their ability to remain inactive for a long time
c. / their inability to multiply in cells
d. / their inability to take over the functions of host cells
____4.Which phrase describes the size of virus particles?
a. / smaller than cellsb. / slightly larger than cells
c. / the same size as cells
d. / much larger than cells
____5.Which disease can be contracted by inhaling infected droplets?
a. / tetanusb. / rabies
c. / flu
d. / Lyme disease
____6.Which of the following stimulates a person’s body to produce chemicals that destroy viruses or bacteria?
a. / antibioticb. / vaccine
c. / toxin
d. / endospore
Modified True/False
Indicate whether the sentence or statement is true or false. If false, change the identified word or phrase to make the sentence or statement true.
____7.One reason that viruses are considered to be nonliving is that they are not made of protein. ______
____8.The inner core of a virus contains genetic material. ______
____9.Unlike the cells of eukaryotes, the cells of bacteria do not have nuclei. ______
____10.Bacteria that are decomposers break down large chemicals in dead organisms into small chemicals. ______
____11.The bacteria that cause Lyme disease are transmitted through tick bites. ______
____12.Bacteria must have a way to break down food to release its energy. ______
Completion
Complete each sentence or statement.
13.Although viruses are nonliving, they act like ______because they harm the cells in which they multiply.
14.Bacteria are called ______because their genetic material is not contained in nuclei.
15.Some bacteria are called ______because they break down large chemicals in dead organisms into small chemicals.
16.Illnesses that pass from one organism to another are called ______diseases.
17.A(n) ______is a substance that stimulates the body to produce chemicals that destroy viruses or bacteria.
18.The ability to ______is the only characteristic that viruses share with living organisms.
Short Answer
Use the diagram to answer each question.
19.Arrange the steps shown in the diagram in their proper sequence.
20.Describe what is happening in part B of the diagram.
21.Identify the structures inside the bacterium in part C of the diagram.
22.Does the diagram show the multiplication of an active virus or a hidden virus? Explain.
23.How does the diagram show that viruses multiply differently than organisms do?
Use the diagram to answer each question.
24.How does the diagram show that bacterial cells are different from the cells of eukaryotes?
Essay
25.A space probe finds no signs of life on another planet. Is it likely that there are viruses on that planet? Explain your reasoning.
26.If a bacterium contained a hidden virus, how would the bacterium be different from a normal bacterial cell?
27.Why are decomposing bacteria and nitrogen-converting bacteria important to farmers?
28.What is an endospore and what is its role in a bacterium?
29.Why is it a good idea to wash your hands after you shake hands with people who have colds?
30.Some people believe that taking antibiotics will help them recover more quickly when they have the flu. Explain what is wrong with this reasoning.
Review for Chapter 7 Test
Answer Section
MULTIPLE CHOICE
1.ANS:ADIF:L2OBJ:A.2.1.1
2.ANS:DDIF:L2OBJ:A.2.1.2
3.ANS:ADIF:L2OBJ:A.2.1.3
4.ANS:ADIF:L1OBJ:A.2.1.1
5.ANS:CDIF:L2OBJ:A.2.3.1
6.ANS:BDIF:L2OBJ:A.2.3.3
MODIFIED TRUE/FALSE
7.ANS:F, cells
DIF:L2OBJ:A.2.1.1
8.ANS:TDIF:L1OBJ:A.2.1.2
9.ANS:TDIF:L2OBJ:A.2.2.1
10.ANS:TDIF:L1OBJ:A.2.2.4
11.ANS:TDIF:L1OBJ:A.2.3.1
12.ANS:TDIF:L1OBJ:A.2.2.2
COMPLETION
13.ANS:parasites
DIF:L2OBJ:A.2.1.1
14.ANS:prokaryotes
DIF:L2OBJ:A.2.2.1
15.ANS:decomposers
DIF:L1OBJ:A.2.2.4
16.ANS:infectious
DIF:L1OBJ:A.2.3.1
17.ANS:vaccine
DIF:L1OBJ:A.2.3.3
18.ANS:multiply
DIF:L1OBJ:A.2.1.1
SHORT ANSWER
19.ANS:
D, A, C, E, B
DIF:L2OBJ:A.2.1.3
20.ANS:
The bacterium is bursting open, and the new viruses that were assembled inside the bacterium are being released.
DIF:L3OBJ:A.2.1.3
21.ANS:
The squiggly lines represent the virus’s genetic material, and the other structures are viral proteins.
DIF:L3OBJ:A.2.1.2
22.ANS:
The diagram shows the multiplication of an active virus, since the virus immediately directs the bacterium to produce viral proteins and genetic material.
DIF:L2OBJ:A.2.1.3
23.ANS:
The diagram shows that viruses can multiply only when they are inside a living cell.
DIF:L3OBJ:A.2.1.1
24.ANS:
The diagram shows that the genetic material of the bacterial cell is not contained inside a nucleus.
DIF:L3OBJ:A.2.2.1
ESSAY
25.ANS:
No. If there is no life on the planet, then there are no cells. Viruses can multiply only inside living cells.
DIF:L2OBJ:A.2.1.1
26.ANS:
The virus’s genetic material would be inserted into a portion of the bacterium’s genetic material.
DIF:L3OBJ:A.2.1.3
27.ANS:
Decomposing bacteria break down chemicals in dead plants, allowing living plants to absorb and use the broken-down chemicals. Nitrogen-converting bacteria make nitrogen compounds that plants need and can use. Both types of bacteria thus help plants survive and grow.
DIF:L3OBJ:A.2.2.4
28.ANS:
An endospore is a thick-walled resting cell that may form inside a bacterium when the cell’s surrounding conditions are unfavorable. It contains the cell’s genetic material and some of its cytoplasm. Because an endospore is resistant to harsh conditions, it can survive for many years and thus help the bacterium survive.
DIF:L2OBJ:A.2.2.3
29.ANS:
People’s cold viruses can spread to their hands when they sneeze, cough, or blow their noses. If you shake hands with someone who has a cold, they might transfer their viruses to your hand. Then the viruses could enter your body if you touched your mouth, eyes, or food.
DIF:L2OBJ:A.2.3.1
30.ANS:
Antibiotics work only against infectious diseases that are caused by bacteria. The flu is caused by a virus. Therefore, antibiotics are not useful against the flu.
DIF:L3OBJ:A.2.3.2