C3 Interaction and Interdependence : Organisms

Question 1

pathogens

Answer 1

A microorganism or other agent (such as viruses) that can cause disease in another organism.

Question 2

lysozyme

Answer 2

An enzyme that functions as a natural defence against bacterial infections by breaking down bacterial cell walls.

Question 3

cilia

Answer 3

Hair-like structures made of microtubules, important for the movement of substances past the cell.

Question 4

commensal bacteria

Answer 4

Bacteria resident on several parts of the human body, including the gut, skin and lungs, without harming the host that can outcompete pathogens for nutrients and space.

Question 5

innate immunity

Answer 5

The first line of defence against pathogens including physical barriers and non-specific defence mechanisms which respond rapidly.

Question 6

phagocytosis

Answer 6

Process by which a cell surrounds and takes in molecules by enclosing them in a membrane-bound vesicle.

Question 7

adaptive immune system

Answer 7

A specialised response to infection mediated by lymphocytes, resulting in immunological memory.

Question 8

lymphocytes

Answer 8

A type of immune cell that is made in the bone marrow and is found in the blood and in lymph tissue.

Question 9

phagosome

Answer 9

Vesicle formed around particles that have been engulfed or ingested by phagocytosis.

Question 10

phagolysosomes

Answer 10

phagosome fuses with the lysosomes

Question 11

antigen

Answer 11

A foreign substance which elicits an immune response; can be a toxin, allergen or part of a pathogen.

Question 12

antibodies

Answer 12

Proteins produced by plasma cells in response to a specific antigen which bind to the antigen and destroy it.

Question 13

helper T lymphocytes

Answer 13

A subpopulation of T-cells required to activate other components of the immune system including B-cells.

Question 14

cytotoxic t lymphocytes

Answer 14

A subpopulation of T-cells which mediate cell-mediated immunity and can kill pathogens directly in the absence of antibodies.

Question 15

humoral immunity

Answer 15

A type of adaptive immune response mediated by antibodies secreted from plasma cells.

Question 16

cell mediated immunity

Answer 16

A type of adaptive immunity mediated by cytotoxic T-cells wherein they directly destroy pathogens without antibodies.

Question 17

zoonotic disease

Answer 17

An infection that can be transmitted from non-human animals to humans.

Question 18

3 types of vaccines

Answer 18

• live pathogen
• DNA plasmid of pathogen
• RNA of pathogen to be translated and antigens produced