PLANTS

Question 1

Name 4 stimuli plants can respond to

Answer 1

water 
sunlight 
gravity 
chemicals 
touch

Question 2

name 3 plant hormones

Answer 2

auxins
givverelins
abscisic acid

Question 3

what is a hormone

Answer 3

chemical messenger produced in one part of the plant and has an effect on another part of the stem

Question 4

what is a tropism

Answer 4

growth or turning movement of a plant in response to an external stimulus

Question 5

what are the 2 types of tropisms

Answer 5

phototropism

genotropism

Question 6

compare phototropism and genotropism

Answer 6

photo: response to light
geotropism: response to gravity

Question 7

What is unilateral light

Answer 7

light coming from one side or direction

Question 8

what is the apical bud

Answer 8

growing point of the stem located at the tip of the stem

Question 9

what is apical dominance

Answer 9

when auxins produced at the tip of the stem inhibit the growth of the branches closer to the tip of stem.

Question 10

where are auxins produced

Answer 10

growing tips of stems.

Question 11

what is the name of the most common auxin

Answer 11

indole acetic acid (IAA)

Question 12

Functions of auxins

Answer 12

• apical dominance
• tropisms
• cell division
• develops flowers and fruits

Question 13

what is apical dominance state

Answer 13

that the main central stem is dominant over other side stems

Question 14

when does apical dominance occur

Answer 14

auxins produced at tip of stem result in the stem growing upwards and inhibits the growth of lateral branches.

Question 15

explain the use of auxins in the fruit industry

Answer 15

plants kept short with more lateral branches = more fruit

fruit closer to ground = easier to pick

Question 16

compare negative and positive tropism

Answer 16

negative = plant moves away from stimulus

positive = plant moves towards stimulus

Question 17

compare uniform light and unilateral light

Answer 17

uniform - directly above

unilateral - 1 direction

Question 18

advantages of phototrophism

Answer 18

leaves recieve light for photosynthesis

promotes pollination

easier seed dispersal

Question 19

where is gibberellins produced

Answer 19

terminal buds of stems and roots in young leaves and in embryos

Question 20

5 functions of gibberellins

Answer 20

stem elongation 
root growth 
flowering 
growth of lateral buds 
seed germination

Question 21

what is abscisic acid

Answer 21

growth inhibitor that counteracts functioning of auxins, it plays a role in helping a plant cope under stress.

Question 22

function of abscisic acid

Answer 22

• dormancy of terminal buds/lateral buds
• dormancy of seeds inhibits germination
• promotes abscission of leaves/fruits
• closing of Stoma during wilting

Question 23

list 5 reasons why plant hormones are used in crop formation

Answer 23

• root formation in cuttings
• production of seedless fruit
• ripening of fruit
• increase in fruit Size
• stimulation of germination

Question 24

list 2 types of plant defence

Answer 24

mechanical and chemical

Question 25

name 3 types of mechanical defence

Answer 25

thorns
prickles
spines

Question 26

how do chemical defences work

Answer 26

posions enemies by affecting feeding, growth and therefore survival