b3

Question 1

viruses

Answer 1

very small

Question 2

bacteria

Answer 2

small
they multiply very quickly
produce toxins that damage cells

Question 3

communicable diseases

Answer 3

pathogens which cause diease that are spread through the air, direct contact or water

Question 4

how to reduce disease

Answer 4

improve hygiene
reduce contact
remove vectors
vaccination

Question 5

human defence system-skin

Answer 5

acts as a barrier

Question 6

human defence system-nose

Answer 6

has hairs which prevent particles from entering your lungs

Question 7

trachea and bronchi

Answer 7

secrete mucus in order to trap pathogens
cilla waft mucus so it can be swallowed

Question 8

stomach

Answer 8

produces hydrochloric acid that kills any pathogens in your mucus or food and drink

Question 9

phagocytosis

Answer 9

engulfing and consuming pathogens

Question 10

producing antibodies

Answer 10

each pathogen has an antigen which an complementary antibody can bind to.

Question 11

producing antitoxins

Answer 11

neutralise the toxins released by the pathogen by binding to them

Question 12

vaccination

Answer 12

contains a dead or inactivated form of the pathogen

Question 13

uses of monoclonal antibodies-pregnancy tests

Answer 13

human chorionic gonadotrophin is present in the urine of women who are pregnant

Question 14

common signs of plant dieases

Answer 14

stunted growth
spots on leaves
area of decay
malformed stems
discolouration

Question 15

nitrate deficieny

Answer 15

stunts growth
convert sugars into proteins
proteins are needed for growth

Question 16

magensium deficiency can cause yellow colour

Answer 16

magnesium is needed for chlorophyll
the green pigment is vital in photosythensis
the lack makes the leaves seem yellowly

Question 17

plant defences-physcial

Answer 17

waxy cutilce-stops entry
cell walls form a physical barrier

Question 18

chemical defences

Answer 18

posions
antibacterial compounds