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WorksheetsB4C
Total questions: 12
Worksheet time: 23mins
B4C In the 1880s, Louis Pasteur developed a method of weakening viruses. The weakened viruses could be injected into healthy individuals.
How is this method effective in fighting viral diseases?
The immune system develops antibodies in response to the weakened viruses.
The weakened viruses attach to unaffected viruses In the host and Interrupt the viral reproductive cycle.
The rate of genetic mutation in the host is decreased due to the introduction of weakened viruses.
Weakened viruses are unable to enter the host organism.
B4C Which of these describes a difference between viruses and cells?
Cells contain protein, and viruses contain only carbohydrates.
Viruses have flagella, and cells have only cilia.
Cells reproduce independently, and viruses require a host to reproduce
Viruses have membranes made of proteins, and cells have membranes made of nucleic
acid.
B4C The human immunodeficiency virus (HIV) often infects and destroys CD4 T cells. These CD4 T cells are one of many kinds of white blood cells that are an important part of the
immune system.
The most common danger related to the destruction of CD4 T cells is -
an increase in the risk of high blood pressure
an increase in the threat of diseases caused by microorganisms and viruses
a decrease in the flow of blood to vital organs
a decrease in the amount of oxygen being transported to tissues
B4C Viruses can be transmitted through air, water, food, insect bites, and direct skin contact. Once a virus gains entry to the body, it invades a host cell in order to -
deactivate the host cell's defenses
synthesize antibodies for defense
metabolize host proteins and grow
access cellular processes for replication
B4C The 1918 influenza epidemic killed between SO million and 100 mill ion people worldwide. This epidemic happened near the end of World War I. More people died from the influenza epidemic than were killed in the war. Which of the following explains why this virus was so deadly worldwide?
Infected soldiers returning from the war spread the virus when they coughed.
Food was scarce because of the war, so people were undernourished, and their immune systems were weakened.
Medical personnel often became ill as a result of exposure to airborne virus particles.
All of the above
B4C The picture shows a 3-D model of a virus called a bacteriophage. Bacteriophages can infect bacteria such as E. coli .
In what way are the bacteriophage and E. coli alike?
They contain antibodies.
They reproduce by mitosis.
They have identical genomes.
They lack membrane-bound organelles.
B4C Models of the human immunodeficiency virus (HIV) and an animal cell are shown below.
What is the difference in the function of the glycoprotein structures of an HIV virion and the cilia of an animal cell?
The glycoprotein structures are used for attachment, and the cilia are used to move fluids surrounding the cell.
The glycoprotein structures are used to obtain nutrition, and the cilia are used to secrete proteins.
The glycoprotein structures are used to provide physical support for the viral envelope, and the cilia strengthen the cell membrane.
The glycoprotein structures are used for defense, and the cilia are used for locomotion.
B4C H1N1 flu is a highly contagious viral infection caused by the influenza A (H1N1) virus. The symptoms of H1N1 flu are listed in the box below. An antiviral agent administered within 48 hours of the appearance of symptoms can reduce the severity of the illness.
Why is it important to administer an antiviral agent to an infected person within 48 hours of the appearance of symptoms?
The H1N1 virus is dormant in cells.
The H1N1 virus replicates quickly.
The H1N1 virus does not mutate.
The H1N1 virus is transmitted through a vector host, such as a mosquito.
B4C A person infected with the human immunodeficiency virus (HIV) may not have any symptoms for a period of time. During this period the virus affects t he body by doing
which of the following?
The virus produces toxins that weaken immune cells and prevent them from reproducing.
The virus damages immune cells while using their machinery to produce copies of itself.
The virus uses nutrients meant for immune cells to fuel its own cellular respiration.
The virus changes the identity of the nucleotides of immune cells to prevent the immune system from functioning normally.
B4C Severe acute respiratory syndrome (SARS) is an illness caused by a coronavirus. Symptoms including a high fever, headaches, and body aches typically occur two to seven days after infection by the virus. SARS is more serious in elderly patients . This in formation suggests that
the reproductive cycle of the SARS virus is -
lysogenic, because the virus is a coronavirus
lytic, because the virus causes respiratory illness
lysogenic, because the virus primarily affects older people
lytic, because of the quick onset of symptoms after infection
B4C A photograph of a virus is shown below.
The projections on the surface of this virus allow the virus to -
move inside a host cell
attach to a host cell
control a host cell's DNA
signal other viruses to infect a host cell
B4C B4C Cold sores are caused by the herpes simplex virus type 1. A company that wants to develop antiviral drugs would ask a research immunologist to study -
the mechanism used by the virus to infect cells
how closely related the virus is to cold viruses
the metabolism of the virus
meiosis in the virus
