transport in plants

Question 1

why do organisms need transport system?

Answer 1

Cells need continuous supply of oxygen and nutrients for respiration and growth while waste products such as the urea, sweat and carbon dioxide needs to be removed. Complex organisms have millions of cells. Most are far away from the environment and cannot get materials directly from it. For bigger size organisms with many cells, the cells found deep within the organism will not come in contact with the external environment directly. Rate of diffusion is too slow to provide oxygen/ nutrients for respiration. A transport system is needed to transport substances to and away from the cells.

Question 2

formula for respiration or what eva

Answer 2

glucose ( nutrient that cell needs ) + oxygen ( release of energy ) –> carbon dioxide + water

Question 3

what is in a plant transport system?

Answer 3

vessels that are found in the roots, stems and leaves.

Question 4

what is the plant transport system used for ?

Answer 4

used to carry water, dissolved mineral salts nad nutrients to all cells in the plant.

Question 5

name of the vessels in the plant transport system

Answer 5

these vessels are called vascular tissues ( transport tissues )
two types:
-> xylem ( water + inside )
-> phloem ( food + outside )

Question 6

why is the xylem in the middle ?

Answer 6

to hold the plant upright

Question 7

What is xylem made up of?

Answer 7

xylem vessels

Question 8

functions of xylem vessels

Answer 8

• transport water and dissolved mineral salts from the roots to the stem and the leaves
• provide mechanical support for the plant

Question 9

what form is sugar in phloem?

Answer 9

sucrose and hot glucose

Question 10

functions of phloem

Answer 10

-conducts / transport manufactured food from leaves to the other parts of the plants

Question 11

distribution of phloem and xylem in the stem

Answer 11

xylem and phloem are grouped together to form vascular bundles. in the stem, the phloem is found on the outer ring and the xylem is found in the inner ring.

Question 12

processes substances use to move in and out of cells

Answer 12

• > diffusion
• > osmosis
• > active transport

Question 13

what is diffusion?

Answer 13

diffusion is the net movement of molecules / particles from a region of higher concentration to a region of lower concentration, down a concentration gradient.

Question 14

what is osmosis?

Answer 14

osmosis is the net movement of water molecules from a solution of higher water potential to a solution of lower water potential through a partially permeable membrane.

Question 15

answering technique for diffusion and osmosis

Answer 15

compare conc / water potential

movement

across a partially permeable membrane via osmosis

process

• > osmosis
• > diffusion

Question 16

why are diffusion and osmosis important in living things?

Answer 16

plants respire all the time and carries out photosynthesis in the presence of light.

Question 17

what is photosynthesis?

Answer 17

a process in which light energy absorbed by chlorophyll is transformed into chemical energy. the chemical energy is used to synthesise carbohydrates from water and carbon dioxide. during the process, oxygen is given out.

Question 18

formula for photosynthesis or what eva

Answer 18

carbon dioxide + water -> (light + chlorophyll) glucose + oxygen

Question 19

what is required for growth?

Answer 19

dissolved mineral salts

Question 20

absorption of water

Answer 20

water potential of cell sap of root hair cell is lower than the water potential of the soil solution
water molecules move from the soil water into the cell sap by osmosis
via the partially permeable cell membrane

Question 21

absorption of dissolved mineral salts

Answer 21

concentration of dissolved mineral salts in cell sap of root hair cell is lower than the concentration of dissolved mineral salts of soil solution

Question 22

after both absorption

Answer 22

the water molecules and dissolved mineral salts then move from one cell to another, by osmosis and diffusion respectively, until they reach the xylem. the xylem will then carry the water and dissolved mineral salts up the stem to the leaves.

Question 23

absorption of carbon dioxide

Answer 23

concentration of carbon dioxide is higher in the air in the environment compared to the intercellular airspace.
concentration of oxygen is higher in the air in the intercellular airspace compared to the air in the environment.
carbon dioxide diffuses from environment into the intercellular airspace through stomata while oxygen diffuses from intercellular airpace to environment through stomata.