Histamine in the blood is secreted by:

What is diapedesis?

(1)  A kind of amoeboid movement.

(2)  The process of filtration of urea in kidney.

(3)  A type of locomotion found in hydra.

(4)  Migration of WBCs into the tissue spaces from blood capillaries.

Identify the given figure and select the correct option 

(1) Neutrophil - phagocytic cell which destroy foreign organisms entering the body

(2) Eosinophil - their number increases during allergic infection

(3) Lymphocyte - small sized non-motile and non-phagocytic

(4) Monocyte - motile and phagocytic in nature

Leucocytes are ______ and ______.

(1) colourless and enucleated

(2) coloured and nucleated

(3) colourless and nucleated

(4) coloured and enucleated

Which of the following sequence is correct in terms of abundance in blood?

1. RBC > WBC > Platelets

2. WBC > RBC > Platelets

3. RBC > Platelets > WBC

4. RBC < WBC > Platelets