4.5

Question 1

what are sclerenchyma and xylem vessels made up of

Answer 1

They’re both made up of bundles of dead cells that run vertically up the stem

Question 2

Both the sclerenchyma fibres and xylem vessels provide ——- to the plant.

Answer 2

support

Question 3

what are the primary funtions of stem?

Answer 3

support and transport

Question 4

what are parentchyma cells and what is their function?

Answer 4

unspecialised cells that act as packing in stems and roots to give support

Question 5

what are collenchyma cells and what is their function?

Answer 5

plants cells with areas of cellulose thickening that give mechanical strength and support to the tissues

Question 6

what are sclerenchyma cells and what is their function?

Answer 6

plant cells that have very thick lignified cell walls and an empty lumen with no living contents

Question 7

what is the function of the epidermis?

Answer 7

to proctect tissue

Question 8

What do xylem vessels transport?

Answer 8

Water and solutes such as salts/ mineral ions

Question 9

What do phloem vessels carry?

Answer 9

The phloem carries sucrose, soluble sugars and organic compounds

Question 10

What is the difference between the structure of sclerenchyma fibres and xylem vessels?

Answer 10

Sclerenchyma fibres are short and tapered with closed ends, whilst xylem vessels are cells joined end to end with their end walls broken down to allow vertical transport of water

Question 11

Where is the xylem, phloem and sclerenchyma located in the stem?

Answer 11

The xylem is located in the inner part of the stem, the phloem is located in the middle and the sclerenchyma is located in the outer part of the stem

Question 12

Which one contains living cells, xylem, phloem or sclerenchyma?

Answer 12

Phloem- it does not contain lignin so cells live.

Question 13

Why dies the xylem and sclerenchyma contain dead cells?

Answer 13

Because they contain lignin.
The cells in the phloem need to be alive to provide energy for active transport when transporting sucrose around the plant.

Question 14

What is translocation?

Answer 14

the active process in phloem, movement of organic solutes up and down the stem

Question 15

What are companion cells?

Answer 15

Cells found in phloem, that link to sieve tubes with many plasmodesmata. They are active cells (many mitochondria) that support the sieve tube cells.