Test: Blood & Lymph - NEET MCQ

Monocytes are phagocytic cells which destroy foreign organisms entering the body. There is no such information that it secretes Heparin.

• Heparin is a naturally occurring anticoagulant produced by basophils and mast cells. In therapeutic doses, it acts as an anticoagulant, preventing the formation of clots and extension of existing clots within the blood.
• Allergic reactions may generally be divided into two components; the early phase reaction, and the late phase reaction. Typically, the infiltrating cells observed in allergic reactions contain a high proportion of lymphocytes, and especially, of eosinophils.
• Basophils are a type of white blood cell. They produce histamine and serotonin that induce inflammation and heparin that prevents blood clotting, although there are less than that found in mast cell granules.
• Neutrophils are phagocytes, capable of ingesting microorganisms or particles.

Hence, the correct option is C

NCERT Reference: Topic “18.1.2 Formed Elements” of chapter 18: Body Fluids & Circulation of NCERT

• Blood has four main components: plasma, red blood cells, white blood cells, and platelets.
• Blood has many different functions, including transporting oxygen and nutrients to the lungs and tissues forming blood clots to prevent excess blood loss.

Hence, the correct option is D

NCERT Reference: Topic “Formed Elements” of chapter: Body Fluids & Circulation of NCERT

• Neutrophils are a type of white blood cell that are known for their ability to rapidly engulf and destroy pathogens. Neutrophils react within an hour of tissue injury and are the hallmark of acute inflammation & engulf pathogens quickly.
• Neutrophils, are the most abundant type of white blood cells and form an integral part of the immune system. These phagocytes are normally found in the bloodstream. However, during the acute phase of inflammation, particularly as a result of bacterial infection, neutrophils leave the vasculature and migrate toward the site of inflammation in a process called chemotaxis.
• They are the predominant cells in pus, accounting for its whitish/yellowish appearance.
• Acidophils and basophils are not phagocytic in nature.
• Monocytes are also phagocytes but take 7-8 hours to reach at the site of injury.

Hence, the correct answer is option (D)
NCERT Reference: Topic “Formed Elements” of chapter: Body Fluids & Circulation of NCERT

The correct answer is Monocytes. 

White blood cells, or leukocytes, are crucial components of the immune system. They can be divided into two main groups: granulocytes and agranulocytes (non-granulocytes).

Granulocytes are white blood cells with granules in their cytoplasm. These granules contain enzymes and proteins that help in the immune response. There are three types of granulocytes:

• Neutrophils: These are the most abundant white blood cells, and they help in fighting off bacterial infections.
• Eosinophils: These cells play a role in combating parasitic infections and are involved in allergic reactions.
• Basophils: These cells are involved in inflammatory and allergic responses, and they release histamine and other mediators.

Agranulocytes (non-granulocytes) are white blood cells without granules in their cytoplasm. There are two main types of agranulocytes:

• Monocytes: These cells are the largest white blood cells, and they can differentiate into macrophages or dendritic cells. They play a role in phagocytosis, which is the process of engulfing and destroying pathogens and cellular debris.
• Lymphocytes: These cells are the primary cells of the adaptive immune response, and they can be further divided into T cells, B cells, and natural killer (NK) cells.

In conclusion, monocytes are non-granulocytes because they do not have granules in their cytoplasm, unlike neutrophils, eosinophils, and basophils, which are all granulocytes. Monocytes play a vital role in the immune system, particularly in phagocytosis and differentiation into other cell types. 

NCERT Reference: Topic “Formed Elements” of chapter: Body Fluids & Circulation of NCERT

Fibrinogen is a plasma protein that is essential for blood clotting. Upon activation, it is converted into fibrin, which forms a mesh that traps blood cells and forms a clot. This process is vital for stopping bleeding and initiating wound healing. Fibrinogen's role in clot formation is a critical aspect of the body's defense mechanism against excessive blood loss.

The correct answer is b, Erythrocyte. The reason is that the other three cell types (Neutrophil, Monocyte, and Lymphocyte) are all white blood cells or leukocytes, while Erythrocyte is a red blood cell.

White Blood Cells (Leukocytes):

• White blood cells are part of the immune system and help protect the body from infections and diseases.
• They are produced in the bone marrow and circulate in the blood and lymphatic system.

The three types of white blood cells mentioned here are:

1. Neutrophils

• They are the most abundant type of white blood cells.
• Their primary function is to engulf and destroy bacteria and other foreign substances.

2. Monocytes

• They are the largest type of white blood cells.
• They mainly function as phagocytes, which means they can engulf and digest cellular debris and foreign particles.

3. Lymphocytes

• They are the second most abundant type of white blood cells.
• They play a crucial role in the adaptive immune response, which includes producing antibodies and activating other immune cells.

Red Blood Cells

Erythrocytes

• Erythrocytes, or red blood cells, are the most common type of blood cell.
• Their primary function is to transport oxygen from the lungs to the body's tissues and remove carbon dioxide.
• They contain a protein called hemoglobin, which binds to oxygen and gives red blood cells their characteristic red color.

In summary, Erythrocyte is the odd one out because it is a red blood cell involved in oxygen transport, while Neutrophils, Monocytes, and Lymphocytes are all white blood cells with roles in the immune system.

NCERT Reference: Topic “Formed Elements” of chapter: Body Fluids & Circulation of NCERT

Platelets, or thrombocytes, are crucial for blood clotting. A significant reduction in their number can lead to clotting disorders, making it difficult for the body to stop bleeding. This can result in excessive blood loss from minor injuries or in surgical situations, posing serious health risks.