Problem 9 - Objective Biology for NEET

Question

The most abundant cell in human blood are (a) Neutrophils (b) Monocytes (c) Lymphocytes (d) None of these

Step-by-Step Solution

Answer

The most abundant cell in human blood are Neutrophils

Step 1: Identify the Most Abundant Cell Type

We have four options: Neutrophils, Monocytes, Lymphocytes, and None of these. The most abundant cell type in human blood are Neutrophils, making up about 50-70% of all white blood cells.

Key Concepts

Human Blood

Human blood is a vital component of the circulatory system and carries out numerous essential functions. It transports oxygen and nutrients to cells and removes waste products like carbon dioxide. Blood also plays a crucial role in regulating body temperature and helps in the healing process when injuries occur.
The composition of blood is complex and consists of both liquid and cellular components. The liquid part is known as plasma, which is mainly water but contains proteins, glucose, electrolytes, and hormones.
The cellular component is made up of different types of blood cells. These are produced in the bone marrow and are a crucial part of the body's defense system as well as carrying out other key functions.

White Blood Cells

White blood cells (WBCs), or leukocytes, are crucial in defending the body against infections and foreign invaders. Unlike red blood cells, which carry oxygen, white blood cells are involved in the immune response. They react to pathogens such as bacteria, viruses, and parasites.
White blood cells achieve this through various mechanisms that include attacking pathogens directly, producing antibodies, and signaling other cells in the immune system.
There are several types of white blood cells, each with specialized functions:

• Neutrophils: These are the most abundant, making up around 50-70% of white blood cells. They are the first responders to microbial infection.
• Lymphocytes: Comprising about 20-40%, they are responsible for antibody production and destroying infected cells.
• Monocytes: These contribute to 2-8% and play a role in breaking down bacteria.
• Eosinophils and Basophils: These are less abundant and involved in allergic reactions and parasitic infections.

By understanding how each type of white blood cell works, we can better appreciate how the body fights off disease.

Blood Cell Types

Blood is composed of different cell types, each carrying out unique functions essential for maintaining health. Understanding these cell types aids in comprehending how blood fulfills its various roles.
The three primary categories of blood cell types are:

• Red Blood Cells (Erythrocytes): Responsible for transporting oxygen throughout the body. They contain the protein hemoglobin, which binds to oxygen.
• White Blood Cells (Leukocytes): Part of the immune system, as discussed, and are crucial for fighting infections.
• Platelets (Thrombocytes): Small cell fragments involved in blood clotting. They help prevent excessive bleeding when injuries occur.

Each of these cell types is generated in the bone marrow and released into the bloodstream to perform its function. Collectively, they ensure the body's organs and tissues get the necessary support and protection needed for optimal functioning.