To investigate the factors necessary for germination

Describe how you set up the apparatus for the investigation.

• Label test tubes A, B, C, D

• Add moistened cotton wool to A, B, C; dry cotton wool to D

• Place 6 cress seeds in each tube

• Add 10 mL of boiled water + oil layer to Tube C (anaerobic conditions)

• Leave Tube B in the fridge; A, C, and D at room temperature for 4 days

What were the results

only the seeds inn test tube A germinated because these had all three factors necessary for germination - heat, oxygen and water.

What is meant by dormancy ins seeds

Period of no germination

How does digestion contribute to successful seed germination

It makes food available for growth

State whether you carried out this investigation using starch agar or protein agar

Starch agar

type of enzyme in the seed that carriues out this digestion

amylase

why were the seeds soaked in water at the start of the investigation

soften the testa

Why is it recommend the you sterilise the seeds

prevents rotting

Why were the split seeds placed open side down on the agar

to expose the enzyme to agar

How did you know that digestive activity had occurred on one of your investigation plates

when iodine was added, clear zones appeared under the seeds

How did you know that digestive had not occurred on one of you digestive plates?

no clear zones appeared

Give one reason why digestive activity had not occurred

the seeds died because they were boiled

Under what conditions did you store the containing the seeds to allow germination to occur

at 20deg celsius for 2 days

how did you test to show that digestion had occured

add iodine

state three factors necessary for successful germination

water, oxygen, suitable temperature

state one advantage of dormancy

prevents overcrowding