Transport In Plant Cells

Question 1

Why don’t plant cells need a transport system?

Answer 1

Plant cells have a large surface area in relation to volume so substances can easily get in and out of the cell and the rate of diffusion for substances is fast enough for its needs.

Question 2

Transport in plants occurs through the vascular bundle which is made up of?

Answer 2

The xylem and the phloem

Question 3

Describe the function of the xylem

Answer 3

The xylem is responsible for the upward movement of water and dissolved minerals from the roots, to the stem, to the leaves then to the rest of the plant.

Question 4

Define the xylem.

Answer 4

Xylems are very long tube like structures made of individual structures that are stacked end to end. These structures are responsible for the upward movement of water and dissolved minerals from the roots to the stem to the leaves then to the rest of the plant.

Question 5

Describe the function of the phloem

Answer 5

The phloem vessel is responsible for transporting sugar and other organic nutrients made from the leaves both up and downwards in the plant

Question 6

Define the phloem vessel

Answer 6

The phloem is made of sieve cells which are entangled living cells. these tubes are connected to another by holes on the end walls between one cell and the next. The phloem is responsible for transporting sugar and other organic nutrients made from the leaves both up and downwards in the plant

Question 7

Name the substances that are transported around the plant

Answer 7

Water, sugar, organic nutrients, minerals

Question 8

Name the substances transported by the xylem and phloem

Answer 8

Xylem- water and dissolved minerals
Phloem- sugar and organic minerals

Question 9

Describe the structure of the cross section of a plant root and stem.

Answer 9

In the root system the xylem forms a central column forming a solid support. The phloem is towards the center, outside the xylem. In the stem, the transport tissue of the xylem and the phloem are grouped into a vascular bundle.

Question 10

How do elongated root hairs increase the TSA for water absorption in a plant?

Answer 10

They have thin walls to speed up the intake of water by osmosis and they have large vacuoles that absorb water quickly and transport it to the next cells .

Question 11

In which part of the plant is the high concentration and low concentration?

Answer 11

High- the root
Low- the plant itself

Question 12

Describe the five steps by which water moves through plants

Answer 12

1) root hairs take in water from the soil by osmosis
2) water moves through the root cortex to the xylem
3) water rises in the xylem vessel because of capillary action
4) water moves through the stem to the leaves
5) water is lost through the leaves , used by transpiration

Question 13

Define the term transpiration

Answer 13

Transpiration is the movement of water through a plant. It is where water is absorbed by the root and passes through plant then is lost by evaporation through the leaves. ( this is sometimes called the transpiration stream)

Question 14

What’re is the transpiration stream?

Answer 14

This is the constant flow of water through the plant.

Question 15

What is evaporation

Answer 15

Evaporation is the conversion of liquid into water vapor as it leaves the cells and enters the air space. This is a process used to cool the plant.

Question 16

Water moves up the the xylem because of three factors, what are they?

Answer 16

Capillarity, root pressure , and transpiration pull

Question 17

Define the terms adhesion and cohesion

Answer 17

Adhesion is when molecules tend to stick to an object and cohesion is when molecules stick together.

Question 18

Define capillarity

Answer 18

Capillarity is when water molecules stick together and to surfaces of narrow tubes and the water rises up the tube. (The narrower the tube, the higher the water will rise) ( xylem vessels are extremely narrow and the attraction between the water molecules and the xylem walls is great)

Question 19

Define root pressure

Answer 19

Root pressure is the pressure created in the root xylem when water is absorbed into the plant from the soil. The pressure there is greater than in the leaf xylem because water is being pulled out of the leaf xylem by transpiration.

Question 20

Define transpiration pull

Answer 20

The transpiration pull happens when cohesive forces hold water molecules together and the loss of water by evaporation in the upper areas of a plant creates a tension that ‘pulls’ water upwards and water is continually lost from the leaves. And so more water is drawn through the xylem.

Question 21

What will happen if the stem and root of a plant are sealed in a poly theme bag for 24hrs

Answer 21

Condensation will form inside the bag . The water would be coming from the leaves instead of from soil.

Question 22

Xylem and phloem are examples of _______ tissue.

Answer 22

Vascular

Question 23

The plant tissue that Carrie’s food materials downward fro, the leaves to the rest of the plant is the _______

Answer 23

Phloem

Question 24

The xylem transports substances in which direction?

Answer 24

Upward

Question 25

Phloem tubes transports substances from where in the plant?

Answer 25

Leaves to the rest of the plant

Question 26

Which vascular bundle transports sucrose and amino acids

Answer 26

Phloem

Question 27

How does water enter the roots from the soil?

Answer 27

Osmosis

Question 28

Plants absorb water through their ______

Answer 28

Roots