Immune System Lines of Defense

What process do phagocytes use to engulf and destroy pathogens?

• Phagocytosis

• Photosynthesis

• Mitosis

• Osmosis

Answer explanation

Phagocytes use phagocytosis to engulf and destroy pathogens. This process involves the cell membrane wrapping around the pathogen, forming a vesicle that is then fused with lysosomes to digest the invader.

Which cells are responsible for producing antibodies?

• B lymphocytes

• T lymphocytes

• Macrophages

• Neutrophils

Answer explanation

B lymphocytes are the cells responsible for producing antibodies, which are crucial for the immune response. T lymphocytes help in cell-mediated immunity, while macrophages and neutrophils are involved in phagocytosis.

What is the role of the second line of defence in the immune system?

• To produce antibodies

• To create a physical barrier

• To initiate an inflammatory response

• To directly attack pathogens

Answer explanation

The second line of defence in the immune system primarily initiates an inflammatory response, which helps to contain and eliminate pathogens, unlike the first line that creates barriers or the third line that produces antibodies.

What is the primary function of macrophages in the immune system?

• To produce antibodies

• To engulf and digest pathogens

• To transport oxygen

• To regulate body temperature

Answer explanation

The primary function of macrophages in the immune system is to engulf and digest pathogens. They play a crucial role in identifying and eliminating harmful microorganisms, making them essential for immune defense.

Which type of cells are primarily involved in the inflammatory response?

• Neutrophils

• B lymphocytes

• Red blood cells

• Platelets

Answer explanation

Neutrophils are the primary cells involved in the inflammatory response. They quickly respond to sites of infection or injury, helping to eliminate pathogens and initiate healing, making them crucial for inflammation.

Select the antibody that can bind to the pathogen shown in the diagram

• A

• B

• C

• D

Answer explanation

Antibody D is specifically designed to recognize and bind to the unique antigens present on the pathogen shown in the diagram, making it the correct choice for targeting this pathogen.

Substances formed by the human body in response to foreign proteins entering the body are called:

• antigens

• antibodies

• platelets

• red blood cells

Answer explanation

Antibodies are substances produced by the immune system in response to foreign proteins, known as antigens. They help identify and neutralize these invaders, making 'antibodies' the correct answer.

Some white blood cells recognize specific​ ​​ __________ as foreign molecules.

• antibodies

• allergies

• platelets

• antigens

Answer explanation

Some white blood cells recognize specific antigens as foreign molecules. Antigens are substances that trigger an immune response, distinguishing them from antibodies, allergies, and platelets.

The body's FIRST lines of defense include:

• B cells

• Mucous Membranes

• Macrophages

• Leukocytes

Answer explanation

The body's first lines of defense include physical barriers like mucous membranes, which trap pathogens. B cells, macrophages, and leukocytes are part of the immune response that acts after these initial defenses.

White blood cells are an important part of the human immune response. Two types of white blood cells, neutrophils and macrophages, act as phagocytes. Phagocytes perform which of the following functions in the human body? 

• They produce antibodies.

• They bind to antigens and develop into B cells

• They form a barrier against pathogens.

• They engulf and destroy bacteria.

Answer explanation

Phagocytes, like neutrophils and macrophages, engulf and destroy bacteria, playing a crucial role in the immune response. The other options involve different immune functions not performed by phagocytes.

Tags

NGSS.MS-LS1-3