Chapter 12- Pathogens

Question 1

How does tuberculosis cause disease

3 points

Answer 1

1. Triggers inflammatory disease infects phagocytes in lungs

2.Bacteria stays dormant stage 1

3.If another factor happens bacteria becomes active and destroys immune system

Question 2

How does HIV turn into AIDS

4 points

Answer 2

1. Proteins bind to complementary CD4 receptor on TH cells.
2. HIV replicate inside TH cells, killing or damaging them.
3. AIDS develops when there are too few TH cells for the immune system to function.
4. Individuals cannot destroy other pathogens

Question 3

How does Tobacco Mosiac Virus affects plants

4 points

Answer 3

Mainly transmitted via infected sap.

Contains ssRNA, which is directly transcribed by host cell to assemble new virions.

Virions enter other cells via plasmodesmata then enter xylem & phloem.

Causes stunted growth & mottled leaves.

Question 4

How does Influenza Virus cause disease
3

Answer 4

1)Injects viral RNA into ciliated epithelial cells of throat & lungs.

2)Viral RNA hijacks cell biochemistry to produce new virions.

3)Cell lysis releases virions

Question 5

How are diseases transferred DIRECTLY

4

Answer 5

Inhalation

Skin-to-skin

Exchange of fluids

Penetrate skin

Question 6

How are diseases transferred INDIRECTLY

3

Answer 6

Consumption of contaminated food

Via a vector

Spores

Question 7

3 physical barriers for the plant to prevent infection

Answer 7

Waxy cutile

Lignin walls

Cellulose cell walls

Question 8

2 mechanical preventions in plants

Answer 8

guard cells close stomata

callose produced

Question 9

What is necrosis

Answer 9

Plants kill off cells to prevent pathogen spreading

Question 10

Chemical defences in plants

2

Answer 10

Alkeloids- Caffine

Terphenoids-Methanols

Question 11

what are explusive refluxes

Answer 11

Body attempting to get pathogen out

Question 12

2 Examples of expuslive refluxes

Answer 12

Sneezing

Coughing

Question 13

3 ways non specific immune system responds to pathogen

Answer 13

Phagocytosis

Inflammination

Lysosomes

Question 14

Outline the process of inflammation
3

Answer 14

1)Vessles release histamines

2)Blood flow & permeability in blood increases

3)WBC and Plasma move into infected tissue

Question 15

2 WBC

Answer 15

Neutrophils

Macrophils

Question 16

How does phagocytosis occur

5 points

Answer 16

1)Phagocyte moves to pathogen

2)Engulfs pathogen via ENDOCYTOSIS and produces a phagosome

3)Phagosome fuses with lysosome

4)Lysosome digests pathogen

5) absorbs nutrients

Question 17

what are two types of specific immune system

Answer 17

cell-mediated

humoral

Question 18

Explain cell-mediated

4

Answer 18

1) T lymphocytes bind to antigen

2)T helper cells produce interlekins

a)to become memory cells

b)secrete killer t cells that produces perforin

Question 19

explain humoral

Answer 19

1) t helper bind to antigen

2)release cytokines that stimulate clonal expansion

3)b cells differentiate into plasma cells

4)plasma cells secrete antibodies

Question 20

What are memory cells

Answer 20

Specialised T helper/ B lymphocyes produced from primary immune responce

Question 21

What does autoimmune disease mean

Answer 21

Immune system produces antibodies against its own tissue