4.1 Disease & Plant Defences

Question 1

What is a disease?

Answer 1

Abnormal condition of an organism impairing its function accompanied by symptoms

Question 2

In what ways can disease be classified?

Answer 2

Timescale
Causes
Infectious or not
Inherited

Question 3

Timescale - what is acute and what is chronic?

Answer 3

Acute - develops quickly e.g angina

Chronic - develops slowly e.g. Chronic bronchitis

Question 4

Causes - disease can be single causal or multi factural give examples of each:

Answer 4

Single - caused by a single mutated gene e.g. Sickle cell anaemia
Multi - genetic and environmental causes E.g. Cardiovascular disease

Question 5

Give examples of infectious and non infectious diseases:

Answer 5

Infectious e.g. HIV

Non e.g. Lung cancer

Question 6

What is a pathogen?

Answer 6

Disease causing organism

Question 7

Pathogens can damage cells e.g. How do malarial parasites work?

Answer 7

By bursting rbc’s

Question 8

Some pathogens produce toxins - what is the difference between exotoxins and endotoxins?

Answer 8

Exo - secreted by living pathogen

Endo - released when pathogen is damaged

Question 9

Cell damage - viruses take over what?

Answer 9

Cell metabolism

Question 10

Cell damage - some protoctists take over cells and do what?

Answer 10

Break them open as they produce a new generation

Question 11

Cell damage - fungi digest living cells doing what?

Answer 11

Destroying them

Question 12

Bacteria produce toxins that damage cells by doing what?

Answer 12

Breaking down membranes
Inactivating enzymes
Interfering with hosts genetic material