Question

Short life span is of?
A. Lymphocytes
B. Monocytes
C. Basophils
D. Neutrophils

Answer 1

Hint: White blood cells (WBCs), also called leukocytes or leucocytes, are the cells of the immune system, which are involved in protecting the body against infectious disease and foreign invaders. The origin of all white blood cells are from multipotent cells in the bone marrow known as hematopoietic stem cells.

Complete Answer:
Leukocytes are found throughout the body, including the blood and lymphatic
system. They are categorized into: neutrophil, eosinophil, basophil, lymphocyte, and monocyte.
1. Lymphocytes- Lymphocytes are divided into B cells and T cells. They are responsible for the specific recognition of foreign agents and their removal from the host. B lymphocytes secrete antibodies, which bind to foreign microorganisms in body tissues and mediate their destruction. Natural killer (NK) cells are also present. They have the ability to kill a variety of target cells. In a healthy person, about 25 to 33 percent of white blood cells are lymphocytes. They have a lifespan of a few months and may also live up to years.

2. Neutrophils- They are the most numerous of the granulocytes. They make up 50 to 80 percent of all white cells. They are often one of the first cell types to arrive at a site of infection, where they engulf and destroy the infectious microorganisms through a process called phagocytosis. The inactivated neutrophils have a lifespan of 5-90 hours and activated neutrophils can usually live for a few days.

3. Basophils- Basophils are the least numerous of the granulocytes and make up less than 1 percent of all white blood cells present in the human body. They have a lifespan of a few days.

4. Monocytes- Monocytes constitute between 4 and 8 percent of the total number of white blood cells in the blood. They move from the blood to sites of infection, where they differentiate further into macrophages. These cells are scavengers that phagocytose whole or killed microorganisms and are therefore effective at direct destruction of pathogens and cleanup of cellular debris from sites of infection. Monocytes have a short lifespan and usually live for around 24 hours and undergo apoptosis soon after.

Hence, the correct option is B, “Monocytes”.

Note: Leukocytes are distinguished by their physical and functional characteristics. The lifespan of white blood cells ranges from 13 to 20 days, after which time they are destroyed in the lymphatic system.