Biology · General Awareness

Viral Diseases and Immunity

807 Questions

Viral diseases and immunity cover the structure, transmission, and diagnosis of viruses like HIV. Questions focus on disease pathways, immune responses, and prevention. Strong knowledge here provides an edge in biology scoring.

HIV and AIDS structureVirus transmission methodsImmune system deficiencyPathogen risk groupsMedical diagnosis methods

Viral Diseases and Immunity Questions

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

Only one of the following four ways through which AIDS can spread

  1. Infected needles and syringes

  2. Through mosquito bites

  3. Looking after AIDS patient

  4. Shaking hands, coughing, sneezing, hugging
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

AIDS is primarily transmitted through the exchange of bodily fluids, such as blood. Sharing needles and syringes is a high-risk activity for HIV transmission, whereas casual contact like shaking hands or mosquito bites does not spread the virus.

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

HIV decreases natural immunity of the body by destroying 

  1. Erythrocytes

  2. Antibodies

  3. T-Lymphocytes

  4. B-Lymphocytes
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The T helper cells (Th cells), also known as CD4 cells, are a type of T cell that plays an important role in the immune system, particularly in the adaptive immune system. HIV is a virus that attacks the CD4+ cells in the immune system. This destroys the CD4+ cells. When the number of CD4+ cells in your body is low, your immune system becomes weaker. This makes it harder to fight infections.

So, the correct answer is 'T-Lymphocytes'.
Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

AIDS is not a disease that can be .......... through the air or by insects.

  1. Circulated

  2. Transferred

  3. Transmitted

  4. Conducted
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Movement through a circuit is called as circulation. This term is generally used for fluid. Transfer is an act of moving of a thing from one place to another place. Conduction is conveying something though a passage or a medium. 
The act of moving something through a medium such as air, water insects etc., is called as transmission. This term is generally used for disease transmission. Therefore, option C is correct. 

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

In context of AIDS, which of the following statement is wrong?

  1. It is a viral disease.

  2. It is sexually transmitted disease.

  3. It can be transmitted through blood transfusion.

  4. It can be transmitted by shakehand and sharing food.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

AIDS (acquired immune deficiency syndrome) is caused by the HIV (human immunodeficiency virus). HIV is transmitted primarily sexually, contaminated blood transfusions, hypodermic needles and from mother to child during pregnancy, breast-feeding.However, AIDS does not spread by mere hand-shake or sharing food.Thus, the correct answer is option (D), 'It can be transmitted by shakehand and sharing food'.

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

Consider the following statements.
AIDS is transmitted
1. By sexual intercourse.
2. By blood transfusion.
3. By mosquitoes and other blood-sucking insects.
4. Across placenta.

  1. 1, 2 and 3 are correct

  2. 1, 2 and 4 are correct

  3. 1, 3 and 4 are correct

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Human immunodeficiency virus, or HIV, is a human retrovirus that infects lymphocytes and causes AIDS. It spreads through body fluid by sexual intercourse, blood transfusion and through the placenta. Thus, the correct answer is option B.

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

AIDS spreads through

  1. Blood transfusion

  2. Placental tissue

  3. Sexual intercourse

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
AIDA is the viral disease caused by HIV virus. It is transmitted through body fluids such as blood, semen, rectal fluids, vaginal fluids, breast milk. These body fluids must come into contact with a mucous membrane or damaged tissue or be directly injected into your bloodstream (by a needle or syringe) blood transfusion, sexual contact, breastfeeding and from HIV-positive pregnant women to their babies in the womb through the placenta and during birth. 
Therefore, the correct answer is option D.
Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

AIDS virus cannot be transmitted by

  1. Sharing needles and syringes

  2. Hugs and hands shakes

  3. Sexual contact

  4. Blood tranfusion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
AIDS is a viral disease transmitted through certain body fluids such as semen, saliva, blood, the breast milk of an AIDS infected person by sexual contact,  breastfeeding from HIV-infected mother can transmit AIDS to the baby and by blood transfusion. During hug and hand shakes, no body fluid is entered into the body from one person to another.Therefore, the correct answer is option B.
Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

Which of the following causes AIDS?

  1. Sharing needles of the syringe

  2. Blood transfusion from infected person to healthy person

  3. Breast feeding to child

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

AIDS is caused by the HIV virus when transferred body fluid from the infected person to the non-infected or healthy ones while sharing infected syringes or blood transfusion or breastfeeding from an infected person to a healthy one, sexual contact etc. Thus, the correct answer is option D.

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

AIDS virus contains or Human immuno deficiency (HIV) virus has protein coat and genetic material which is





  1. Single stranded RNA with protein

  2. Double stranded RNA

  3. Single stranded DNA with protein

  4. Double stranded DNA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

HIV virus is a retrovirus which contains single stranded RNA surrounded by protein coat (core shell) as genetic material. It causes AIDS.

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

HIV causes reduction of

  1. T-helper cells only

  2. All T-cells

  3. B-cells only

  4. Both B and T-cells
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The T helper cells are a type of T-cell that plays an important role in the immune system, particularly in the adaptive immune system. They help the activity of other immune cells by releasing T cell cytokines. When the HIV infects the man it enters into the T-helper cells for replication and they utilize energy from T- help cells. By the viral replication, T-helper cells get damaged and gradually reduced their numbers.

Multiple choice zoology infectious diseases cancer and aids hiv and aids immunity related disorders and problems

At which stage, of HIV infection does one usually show symptoms of AIDS?

  1. Within 15 days of sexual contact with an infected person

  2. When the infecting retrovirus enters host cells

  3. When viral DNA is produced by reverse transcriptase
  4. When HIV replicates rapidly in helper T-lymphocytes and starts to reduce the number of T$ _H$ cells by destroying them.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

There are three stages in the development of AIDS. 

The first stage is 'acute HIV infection' which is the earliest stage of HIV and develops within 2-4 weeks after a person is infected with HIV and here people have flu-like symptoms.
The second stage is 'chronic HIV infection' where HIV continues to multiply in the body but at very low levels.
The last and final stage of HIV infection is AIDS. AIDS is diagnosed when a person with HIV has a T lymphocytes count of less than 200 cells/cubic mm and/or one or more opportunistic infections. HIV uses the machinery of these T lymhocytes for replication and destroys them rapidly. Thus, the correct answer is option D.