2.5 transport systems in plants

Question 1

i can identify organs in plants

Answer 1

leaves stems and roots of plants

Question 2

transport systems in plants

Answer 2

are needed in plants to move water and minerals upwards from the roots to the leaves and move sugars mainly downwards from leaves to rest of plant

Question 3

root hair cells

Answer 3

extended surface area and large vacuole to allow absorption of water by osmosis

Question 4

xylem vessels

Answer 4

transport water and minerals upwards from the roots to the aerial parts of plants

Question 5

structure of xylem

Answer 5

hollow tubes lines with rings or spirals of strong waterproof lignin the hollow tubes have been formed from remaining walls of dead cells and create system of pipes to allow transport of water and minerals upwards from roots

Question 6

why xylem vessels are lignified

Answer 6

to allow them to cope with pressures of changes that take place when water is being transported upwards by the transpiration pull without collapsing themselves

Question 7

how is movement of water and minerals from the soil to air

Answer 7

water and minerals are moved into root hair cells from soil by osmosis and diffusion and the transporters upwards through the xylem vessels by transpiration pull. the transpiration pull moves water and minerals up to leaves where they exit xylem vessel to enter either the palisade mesophyll or use for raw material for photosynthesis or the air spaces in the spongy mesophyll layer where the water becomes water vapour will evaporate out of lead through stomata by transpiration

Question 8

definision of transperation

Answer 8

movement of water through a plant and loss of water from the leaves of plants by evaporation

Question 9

structures of a sandwich diagram

Answer 9

filling layer between uppper and lower eperdermis are the palisade mesophyll and spongy mesophyll the palysade mesophyll is tightly packed layer of large rectangular cells that are filled with chloroplasts. This is where most photosynthesis takes place. Spongy mesophyll layer of irregularly shaped cells full of air spaces to allow gas’s exchange between stomata in lower eperdermis and palisade mesophyll cells. the internal structure also contains vessels called xylem and phloem to transport water raw material in photosynthesis and sugars product from photosynthesis

Question 10

external features of leaf

Answer 10

very thin structure with a large surface area to absorb sunlight the top outer area surface of leaves are composed of layer of waxy cuticle and eperdermal cells the waxy cuticle is waterproof to prevent rain from entering the leaf the eperdermak cells are transparent to let light energy pass through them to cell layers below the lower surface is another layer of transparent eperdermis but the lower wperdermis many hairs cells and stomata are distributed the gaurd cells control size of stamata and so control gas exchange of lead allowing c02 to enter for photosynthesis and excess of 02 to escape water vapour is also lost through stomata in process called transpiratiin

Question 11

structures of a lead through which most water is lost by evaporation

Answer 11

through stomata that are found between gaurd cells mainsly at lower eperdermis of lead

Question 12

how plants can control water loss

Answer 12

via transpiration by opening and closing their stomata a pair of gaurd cells control the size of the stoma between them when the stomata is closed water loss through the stomata prevented stomata mainly closed at night and open during day

Question 13

factors that affect rate of transportation

Answer 13

temperature
surface area of lead
wind speed
humidity

Question 14

effect of each factor on the rate of transpiration

Answer 14

as temp, surface area and wind speed increase rate of transpiration increases. as temp surface area and wind speed decrease the rate of transpiration decreased. as the humidity increase the rate of transpiration decreases and the opposite

Question 15

potometre measures transpiration

Answer 15

apparatus that can be used to measure the transportation rate of plant a potomtre is made up of pieces of thin glass tubing filled with coloured water with one end of the tubing in container while other is attached to a stem cutting of a transpiration plant. an air bubble in the thin glass tube can be created and then as the plant transpires the bubble will move alone glass tube towards plant. by measuring distance travelled by the air bubble in a given period of time u can calculate rate if transpiarwtoon

Question 16

function of phloem vessel

Answer 16

transports sugar from leaves where they are made by photosynthesis to other parts of plant

Question 17

structure of phloem

Answer 17

living made up of two diff types of cell sieve tube witj sieve plates and companion cells. sieve tubes have no nucleus and holey end walls to allow transport of cytoplasm containing dissolved sugars between neighbouring phloem cells. A companion cell has an enlarged nucleus that controls both itself and its neighbouring sieve plate crlls