B4.6/B4.7/B4.8 - Plant's organs and organ systems

Question 1

epidermal tissue

Answer 1

covers surface of plant
-protects it
-eg waxy substance = waterproof

Question 2

palisade mesophyll

Answer 2

-contain chloroplasts
-lots of photosynthesis

Question 3

spongy mesophyll

Answer 3

-contains chloroplasts for photosynthesis
-has big air spaces to allow for diffusion

Question 4

xylem/phloem

Answer 4

transport cells
-xylem = carry water
-phloem = carry dissolved mineral ions

Question 5

meristem tissue

Answer 5

tips of roots/shoots
-made of rapidly dividing plant cells
-differentiate into other needed specialised cells

Question 6

eg of plant organs

Answer 6

-stem
-leaves
-roots

Question 7

stomata

Answer 7

-allow gases to move in/out

Question 8

guard cells

Answer 8

-allow opening/closing of stomata

Question 9

phloem cells

Answer 9

-living cells
-move sugars from roots to plant growing areas where energy is needed
-transports them to storage units to be used during the winter

Question 10

translocation

Answer 10

the movement of dissolved sugars from leaves to rest of plant

Question 11

xylem cells

Answer 11

-dead cells
-transports water from soil to rest of plant

Question 12

Purpose of transport within plants (5points)

Answer 12

-sugar = respiration
-material for growth
-mineral ions = production of protein
-water = support + photosynthesis

Question 13

Purpose of stomata

Answer 13

-allow air into leaves
-eg co2 diffuses into air spaces then into cells
-at the same time oxygen from photosynthesis is removed by diffusion

Question 14

transpiration

Answer 14

-loss of water vapour through stomata
-when they are opened to allow gas exchange in plants

Question 15

transpiration stream

Answer 15

-constant pull of water through xylem cells to replace water lost through transpiration

Question 16

Factors increasing rate of transpiration

Answer 16

-increase in light intensity
-hot/dry/windy weather conditions
-increase in temp

Question 17

ways of controlling water loss

Answer 17

-waxy, waterproof layer (cuticle) prevent uncontrolled water loss

Question 18

effects of too much water loss

Answer 18

-wilting = reduces SA so less water is lost through evaporation
-stomata close = stops photosynthesis + risks of overheating

Question 19

potometer

Answer 19

-measures transpiration rates
-shows how uptake of water in a plant changes in different conditions