Question

Which of the following is true about leucocytes?

• A. They undergo diapedesis or squeeze through capillary walls
• B. Sudden fall in number indicates cancer
• C. Produced in thymus
• D. Enucleate

Answer 1

The correct option is A They undergo diapedesis or squeeze through capillary walls

A. Leucocytes or White blood cells (WBCs) can squeeze out through capillary walls into the tissue and reach the site of injury. This process is known as diapedesis.

B. Sudden fall in number of leucocytes is called leucopenia and this increases the chances of infection. Cancer is caused when the number of leucocytes is increased abnormally and this condition is called leukemia (the cancer of white blood cells).

C. Leucocytes are produced in bone marrow. B cells which are a type of lymphocytes (agranular leucocytes) are also produced in spleen and lymph nodes.

D. Leucocytes contain a nucleus and hence they are nucleated.

Hence, statement A is true.

So, the correct answer is 'They undergo diapedesis or squeeze through capillary walls'.