1.
What is the approximate number of lymphocytes present in a healthy human?
Correct Answer
D. 1 trillion
Explanation
The approximate number of lymphocytes present in a healthy human is 1 trillion. Lymphocytes are a type of white blood cell that plays a crucial role in the immune system. They help the body fight off infections and diseases. The large number of lymphocytes in the body is necessary to ensure a strong and effective immune response.
2.
How long is the lifespan of a T- cell?
Correct Answer
B. 4-5 years
Explanation
T-cells are a type of white blood cell that play a crucial role in the immune system. They are responsible for recognizing and attacking infected or abnormal cells in the body. The lifespan of T-cells can vary depending on the specific type and the conditions they are exposed to. However, on average, T-cells can live for around 4-5 years. This allows them to provide long-term protection against pathogens and maintain immune system function over an extended period of time.
3.
The B- cells produce the antibodies in response to which cell?
Correct Answer
A. Helper T-cells
Explanation
Helper T-cells are responsible for activating B-cells to produce antibodies. When an antigen enters the body, it is presented to Helper T-cells by antigen-presenting cells. The Helper T-cells then release chemical signals that stimulate B-cells to differentiate into plasma cells, which produce and release antibodies. These antibodies bind to the antigen and help in its neutralization or elimination from the body. Therefore, Helper T-cells play a crucial role in the immune response by triggering the production of antibodies by B-cells.
4.
What does the letter T stand for in T - lymphocytes?
Correct Answer
D. Thymus
Explanation
The letter T in T-lymphocytes stands for Thymus. T-lymphocytes are a type of white blood cell that are produced in the thymus gland, which is a small organ located in the upper chest. The thymus plays a crucial role in the development and maturation of T-lymphocytes, which are an important part of the immune system.
5.
What do you mean by apoptosis?
Correct Answer
A. Programmed Cell death
Explanation
Apoptosis refers to programmed cell death, which is a natural process that occurs in multicellular organisms. It is a controlled and regulated process where cells undergo self-destruction. This mechanism plays a crucial role in various biological processes, including development, tissue homeostasis, and immune response. Unlike accidental cell death, apoptosis is a carefully orchestrated process that eliminates unwanted or damaged cells without causing inflammation or harm to surrounding tissues. Cell regeneration, on the other hand, involves the growth and replacement of new cells, while programmed cell division refers to the controlled replication of cells.
6.
Children who are born with defects in their cellular immune system are more likely at risk of infection with __________.
Correct Answer
C. Listeria monocytogenes
Explanation
Children who are born with defects in their cellular immune system are more likely at risk of infection with Listeria monocytogenes. This is because Listeria monocytogenes is an intracellular pathogen that can invade and replicate within host cells. A functional cellular immune system is crucial for recognizing and eliminating intracellular pathogens. Therefore, children with defects in their cellular immune system are unable to effectively clear Listeria monocytogenes infection, making them more susceptible to this particular pathogen.
7.
Which of the following cell mainly mediate Cell-mediated immunity?
Correct Answer
B. T-lympHocytes
Explanation
T-lymphocytes mainly mediate cell-mediated immunity. This is because T-lymphocytes are a type of white blood cell that play a crucial role in the immune system by recognizing and destroying infected cells or cancer cells. They are responsible for coordinating and regulating the immune response, and they also help in the activation of other immune cells. B-lymphocytes, on the other hand, are responsible for producing antibodies and mediating humoral immunity. Mast cells are involved in allergic reactions, and white blood cells is a general term that includes various types of immune cells, including T-lymphocytes.
8.
Which of the following includes all the various types of T - cells?
Correct Answer
A. Killer cells, Helper cells, Suppressor cells, and Memory cells
Explanation
The correct answer is Killer cells, Helper cells, Suppressor cells, and Memory cells. This answer includes all the various types of T-cells, which are important components of the immune system. Killer cells, also known as cytotoxic T-cells, are responsible for destroying infected cells. Helper cells, or T-helper cells, assist in coordinating the immune response. Suppressor cells, or regulatory T-cells, help to regulate and suppress immune responses. Memory cells, or memory T-cells, are long-lived cells that "remember" previous infections and can mount a quicker and stronger response upon re-exposure to the same pathogen.
9.
What is the full form of CMI?
Correct Answer
D. Cell-Mediated Immunity
Explanation
Cell-Mediated Immunity (CMI) is the correct full form. CMI is a type of immune response that involves the activation of T cells to fight against intracellular pathogens, such as viruses and certain bacteria. It plays a crucial role in the body's defense against infections and the rejection of transplanted tissues. This immune response is mediated by the action of T cells, hence the term "cell-mediated."
10.
Which of the following cells is most commonly called a competent lymphocyte?
Correct Answer
A. T-lympHocytes
Explanation
T-lymphocytes, also known as T cells, are the most commonly referred to as competent lymphocytes. These cells are a type of white blood cell that play a crucial role in the immune response. T-lymphocytes are responsible for recognizing and destroying pathogens, infected cells, and cancer cells. They are also involved in regulating the immune system and coordinating immune responses. Therefore, T-lymphocytes are considered the most competent lymphocytes due to their diverse functions and importance in immune defense.