B5 - Communicable Diseases - B5.9, B5.10, B5.11

Question 1

Give two ways in which the skin prevents pathogens getting into your body.

Answer 1

Antimicrobial secretions / acts as a barrier / restores itself / covered in microorganisms that acts as an extra barrier to the entry of pathogens

Question 2

How (other than the skin) does the body try to prevent pathogen entry?

Answer 2

Hairs in nose / mucus in nose / mucus in trachea and bronchi with cilia cells / stomach acids kills them when you swallow

Question 3

What is the second line of defence against disease?

Answer 3

White blood cells in the bloodstream for a general response

Question 4

Give two ways that white blood cells can nullify pathogens

Answer 4

By producing antibodies / by ingesting microorganisms / by producing antitoxins

Question 5

What are aphids and what do they do?

Answer 5

Aphids are insects that attack plants in large numbers, feeding off their sugar-rich phloem sap. They can act as vectors of disease - moving them from one plant to another through their mouthparts

Question 6

How farmers often try to get rid of aphids?

Answer 6

By using pesticides, biological pest control, or releasing their predators - such as ladybirds and their larvae, which would eat them

Question 7

Give 3 examples of disease symptoms in plants

Answer 7

Stunted growth / discolouration / spots on the leaves / areas of decay / abnormal growths / malformed stems / presence of visible pests

Question 8

How can plant diseases be treated?

Answer 8

They can be sprayed with pesticides if pests are the problem / given whatever they have a deficiency of / they can be given anti fungal treatments

Question 9

What do people do if the plant cannot be treated?

Answer 9

Remove it from the woodland as soon as possible to avoid spread of the disease

Question 10

Give 2 examples of physical barriers for plants against disease

Answer 10

Cellulose cell walls that are rigid and strong / Bark on trees or layers of dead cells on stems that are hard for pathogens to penetrate as if they are shed, so too are the pathogens / Waxy cuticle layers act as a barrier / leaf fall

Question 11

Give 2 examples of plant defences against being eaten

Answer 11

Thorns / poisons that make animals feel unwell / hairy stems and leaves / leaves that collapse or curl when touched / plants that look ill or diseased on purpose to fool animals into not eating them