Plant Transport Systems and Transpiration B2

Question 1

How are plants specialised for the uptake of water and minerals?

Answer 1

Root hair cells have tiny hair-like extensions to increase the surface area of the cell for more absorption of water and minerals. Plants also have thin membranes which helps absorption.

Question 2

What three essential minerals do plants need to be healthy?

Answer 2

Plants need nitrates, phosphates and potassium to stay healthy

Question 3

How do water and minerals enter plants?

Answer 3

Water enters the root hair cells by osmosis and minerals enter the root hair cells by active transport.

Question 4

What are the two names of the transport tissue in plants?

Answer 4

Xylem and phloem

Question 5

What do phloem vessels transport?

Answer 5

Phloem vessels transport glucose produced in the leaf by photosynthesis to other parts of the plant.

Question 6

What do xylem vessels transport?

Answer 6

Xylem vessels transport water and minerals from the soil to other parts of the plant.

Question 7

What is translocation?

Answer 7

Translocation is the movement of glucose from the leaf to other parts of the plant by the phloem.

Question 8

How are xylem vessels adapted to their function?

Answer 8

Xylem vessels are made of dead cells. They have a thick cell wall made of cellulose and hollow lumen.

Question 9

How are phloem vessels adapted to their function?

Answer 9

Phloem vessels are made of living cells. They have lots of mitochondria to release energy to move substances by active transport.

Question 10

What is transpiration?

Answer 10

Transpiration is the upward flow of water from the roots to the leaves, from where it evaporates into the atmosphere.

Question 11

What are the benefits of transpiration?

Answer 11

The constant stream of water from the ground keeps the plant cool. It also provides the plant which a constant supply of water for photosynthesis.

Question 12

What is the equation for finding the rate of transpiration?

Answer 12

The rate of transpiration = volume of water lost ➗ time

Question 13

What equipment is used to measure the transpiration rate?

Answer 13

A potometer is used to measure the rate of transpiration.

Question 14

How do plants lose water and why is this bad?

Answer 14

Plants can lose water through the stomata due to diffusion (there is more water in the plant then in the air). The stomata can be closed to reduce water loss however this will reduce the intake of carbon dioxide and limit photosynthesis.

Question 15

What factors affect the transpiration rate?

Answer 15

Transpiration rate is affected by an increase in light intensity (the brighter the light the high transpiration rate), an increase in temperature (the warmer it is the faster transpiration happens) and an increase in wind velocity (the more wind movement transpiration will happen faster)

Question 16

What adaptions do plants have to reduce water loss?

Answer 16

Leaves usually have a waxy cuticle which makes the upper surface of the leaf waterproof. Most stomata are found on the lower surface of a leaf where it’s darker and cooler, this helps slow down diffusion. The bigger the stomata and the more stomata means more water is lost, plants in hot climates will have less and smaller stomata.

Question 17

When do stomata open and close?

Answer 17

Stomata close automatically when supplies of water start to dry up. Open stomata allow gases in and out for photosynthesis. Stomata are sensitive to light, so they are open during the day and close at night.