Disease, Defence & Treatment GLOSSARY KEYWORDS

Question 1

A micro-organism that causes disease

Answer 1

Pathogen

Question 2

A protein originating on a cell surface that acts as a marker to other cells

Answer 2

Antigen

Question 3

an organism too small to be seen by the naked eye

Answer 3

micro-organism

Question 4

a protein, secreted by lymphocytes that neutralises toxins

Answer 4

antitoxin

Question 5

a type of white blood cell that detects specific antigens

Answer 5

lymphocyte

Question 6

a test for the presence of specific antigens

Answer 6

immunoassay

Question 7

identical, specific proteins produced in large numbers (by hybridomas)

Answer 7

monoclonal antibodies

Question 8

micro-organisms that have a cell-wall, but no nucleus

Answer 8

Bacterium

Question 9

an illness

Answer 9

disease

Question 10

a specific protein (produced by a lymphocyte) that attaches to an antigen

Answer 10

antibody

Question 11

the parasite that causes malaria

Answer 11

plasmodium

Question 12

when it can be passed from person to person

Answer 12

communicable

Question 13

drug tests in which neither the doctor nor the patient know whether the pill is the drug or placebo

Answer 13

double-blind trials

Question 14

the ability to produce antibodies against a specific pathogen so quickly that symptoms are not experienced

Answer 14

immunity

Question 15

the bacterium that causes chlamydia

Answer 15

chlamydia trachomatis

Question 16

a chemical taken in a drugs trial that has no effect on the organism

Answer 16

placebo

Question 17

the use of chemicals (rather than radiation) to treat cancer

Answer 17

chemotherapy

Question 18

the community of micro-organisms occurring naturally on the skin surface

Answer 18

skinflora

Question 19

a cell (formed from fusing a B-lymphocyte and a tumour cell) that divides indefinitely to produce monoclonal antibodies

Answer 19

hybridoma

Question 20

a type of white blood cell that engulfs/ingests non-self material

Answer 20

phagocyte

Question 21

the genus of mosquito that transmits the malarial parasite, plasmodium

Answer 21

anopheles

Question 22

an injection used to provide immunity to a particular disease

Answer 22

vaccination

Question 23

pathogen

Answer 23

micro-organisms that cause disease

Question 24

Name the 4 types of microorganisms that can cause disease?

Answer 24

Bacteria
Fungi
Viruses
Single celled organisms (protists)

Question 25

How does a bacterial cell differ from an animal cell?

Answer 25

A bacterial cell has a cell wall A bacterial cell does not have a nucleus

Question 26

What surrounds a virus?

Answer 26

A protein coat called a capsid

Question 27

Does a virus have a nucleus?

Answer 27

No, it contains genes within the protein coat

Question 28

What is a communicable disease?

Answer 28

A disease that can be transmitted from one host to another

Question 29

State the 6 ways in which a communicable disease be spread.

Answer 29

Aerosol Body fluids Contact Contaminated food Insects Water

Question 30

What is an aerosol?

Answer 30

A droplet of water in the air, such as from a sneeze or cough

Question 31

Name a disease spread by water and suggest how water can be made safe to drink

Answer 31

Cholera Boil water, filter it or add chlorine

Question 32

Name a disease spread by contaminated food and suggest how it can be prevented

Answer 32

Salmonella Cook food thoroughly

Question 33

How do the skin flora help defend against disease?

Answer 33

Make it difficult for pathogens to become established

Question 34

How do platelets help defend against disease?

Answer 34

They form a blood clot to seal the wound The clot prevents entry of microbes and stops blood loss

Question 35

Which type of white blood cell deals with specific pathogens?

Answer 35

Lymphocytes - they produce antibodies which are specific to the bacterial or viral antigens

Question 36

What 2 types of proteins do lymphocytes produce to deal with bacteria?

Answer 36

Antibodies Antitoxins

Question 37

What is an antigen?

Answer 37

A molecule on the outside of the bacteria or virus that is recognised by the immune system as foreign. It triggers the secretion of antibodies which are specific to the antigen.

Question 38

What 2 types of cells do lymphocytes produce

Answer 38

Plasma cells - clones of the lymphocyte which secrete antibodies specific to the antigen Memory cells - cells that remember the antigen if it gets into the body again