inerworkings of plants topic 4 biod

Question 1

what is the cell walls role in the cell

Answer 1

stops plant from bursting when water enters by osmosis making it turgid

include turgid

Question 2

what type of glucose is cellulose made of

Answer 2

beta glucose

Question 3

what type of bonds are formed between beta glucose in cellulose

Answer 3

1,4 glycosidic bonds

Question 4

what has to happen in the glucose of cellulose for the bonds between them to form

Answer 4

every other glucose has to be inverted 180 degrees

Question 5

Compare the structure of cellulose with starch.

Answer 5

Cellulose is made of β-glucose, starch is made of α-glucose

Cellulose has straight, unbranched chains; starch is branched (amylopectin) or coiled (amylose)

Cellulose forms hydrogen bonds between chains, starch does not

Question 6

Describe the structure of cellulose.

Answer 6

every other beta glucose is flipped and joined by 1,4 glycosidic bonds forming long straight chains. chains form hydrogen bonds between eachother forming microfibrils.

Question 7

Explain why cellulose is strong.

Answer 7

Cellulose chains form microfibrils due to many hydrogen bonds between chains, which provide high tensile strength

Question 8

what is xylems function

Answer 8

to transport water and dissolved minerals through the plant from the roots to the leaves

Question 9

Describe the structure of xylem tissue.

Answer 9

long hollow tubes of dead lignified cells with pits for lateral movement.

Question 10

Explain how the structure of xylem is related to its function

Answer 10

pits allow sideway movement of water. lignin supports the cell and withstands high pressure. hollow tubes allow unrestricted movement of water

Question 11

what does passive mean in the context of movement

Answer 11

doesnt require any energy

Question 11

why would any cell have a chloroplast

Answer 11

to carry out photosynthesis

these word exactly or redo

Question 12

Parenchyma cells are found between the vascular bundles in a plant stem. Suggest a function for these cells

Answer 12

for storing nutrients and provide support to withstand waters pressure

Question 13

how would you identify sclerenchyma

Answer 13

unspecialised cells found near vascular bundles with large cytoplasm

Question 14

. Compare the phloem and xylem. (4 marks)

Answer 14

Phloem = living cells, Xylem = dead cells

Phloem moves sugars, Xylem moves water and minerals

Phloem flow = both directions, Xylem = one-way

Phloem has sieve plates and companion cells, Xylem has lignin and no end walls