Communicable Diseases

Question 1

pathogen

Answer 1

a microorganism that causes disease

Question 2

direct transmission

Answer 2

passing a pathogen from host to new host with no intermediary

Question 3

transmission

Answer 3

passing a pathogen from an infected individual to an uninfected individual

Question 4

indirect transmission

Answer 4

passing a pathogen from host to new host via a vector

Question 5

vector

Answer 5

an organism that carries a pathogen from one host to another

Question 6

callose

Answer 6

a large polysaccharide deposit that blocks old phloem sieve tubes

Question 7

inflammation

Answer 7

swelling and redness of tissue caused by infection

Question 8

mucous membrane

Answer 8

specialised epithelial tissue that is covered by mucus

Question 9

primary defences

Answer 9

those that prevent pathogens entering the body

Question 10

antigen-presenting cells

Answer 10

a cell that isolates the antigen from a pathogen and places it on the plasma membrane so it can be recognised by other cells in the immune system

Question 11

clonal selection

Answer 11

selection of a specific B or T cell that is specific to the antigen

Question 12

cytokines

Answer 12

hormone-like molecules used in cell signalling to stimulate the immune response

Question 13

neutrophil

Answer 13

a type of white blood cell that engulfs foreign matter and traps it in a phagosome which fuses with lysosomes to digest it

Question 14

opsonins

Answer 14

proteins that bind to the antigen on a pathogen and then allow phagocytes to bind

Question 15

antibodies

Answer 15

specific proteins released by plasma cells that can attach to pathogenic antigens

Question 16

B memory cells

Answer 16

remain in the blood for a long time providing long-term immunity

Question 17

clonal expansion

Answer 17

an increase in the number of cells by mitotic cell division

Question 18

interleukins

Answer 18

signalling molecules that are used to communicate between different white blood cells

Question 19

plasma cells

Answer 19

derived from B lymphocytes, they manufacture antibodies

Question 20

T helper cells

Answer 20

release signalling molecules to stimulate the immune response

Question 21

T killer cells

Answer 21

attack and destroy our own body cells that are infected by a pathogen

Question 22

T memory cells

Answer 22

remain in the blood for a long time providing long-term immunity

Question 23

T regulator cells

Answer 23

involved with inhibiting or ending the immune response

Question 24

agglutinins

Answer 24

antibodies that cause pathogens to stick together

Question 25

anti-toxins

Answer 25

antibodies that render toxins harmless

Question 26

opsonins

Answer 26

antibodies that make it easier for phagocytes to engulf the pathogen

Question 27

primary immune response

Answer 27

the initial response caused by a first infection

Question 28

secondary immune response

Answer 28

a more rapid and vigorous response caused by a second or subsequent infection by the same pathogen

Question 29

active immunity

Answer 29

where the immune system is activated and manufactures its own antibodies

Question 30

artificial immunity

Answer 30

immunity achieved as a result of medical intervention

Question 31

epidemic

Answer 31

a rapid spread of disease through a high proportion of the population

Question 32

natural immunity

Answer 32

achieved through normal life processes

Question 33

passive immunity

Answer 33

achieved naturally by another then antibodies are passed to the individual through breast feeding or injection

Question 34

vaccination

Answer 34

a way of stimulating an immune response so immunity is achieved

Question 35

antibiotic

Answer 35

a chemical which prevents the growth of microorganisms (antibacterial or antifungal)

Question 36

personalised medicine

Answer 36

development of designer medicines for individuals

Question 37

synthetic biology

Answer 37

the re-engineering of biology- production of new molecules that mimic natural processes or use of natural molecules to produce new biological systems that do not exist in nature

Question 38

a host

Answer 38

an organism in which pathogens live, creates a good habitat but takes nutrition & damages in the process

Question 39

why do bacteria and fungi often live in vascular tissue of plants

Answer 39

have access to the plants nutrients and water to replicate around the plant

Question 40

social factors that affect direct transmission

Answer 40

overcrowding, poor ventilation/diet/health, homelessness, living/working with migrants from where disease is common

Question 41

protoctists, bacteria and fungi grow and reproduce more rapidly in...

Answer 41

warm and moist conditions, warmer climates (damaged/even killed by cool climates)

Question 42

passive defences in plants

Answer 42

defences present before infection, prevent entry and spread of pathogen

Question 43

active defences in plants

Answer 43

when pathogens attack specific chemicals in their cell walls, it can be detected by plant cells that fortify the defences

Question 44

why are most pathogens killed by the stomach

Answer 44

very acidic (pH1-2) which denatures its enzymes

Question 45

why immunity takes time to develop

Answer 45

body has to encounter the pathogen lymphocytes must divide to form clones B lymphocyte have to secrete enough antibodies T cells have to be produced and destroy all infected cells .....in which this is enough time for the pathogen to replicate and cause illness

Question 46

interferon

Answer 46

released by many cells to inhibit virus replication and stimulate T killer cells

Question 47

herd vaccination

Answer 47

using a vaccine to provide immunity to almost all population at risk- once enough immune, disease can no longer spread

Question 48

ring vaccination

Answer 48

used when a new case of disease is reported by vaccinating all people in immediate vicinity of it

Question 49

process of an epidemic

Answer 49

when pathogens undergo genetic mutations which changes their antigens so memory cell produced by vaccination won't recognise them --> pathogen transmitted --> some unstable so regularly undergo changes --> epidemic rise

Question 50

what happens if you leave the disease area

Answer 50

no further exposure to pathogens so memory cells will die --> no immunological memory

Question 51

transmission of malaria

Answer 51

bite from an infected femal Anopheles mosquito which carries the Plasmodium vivax parasite