Germination + Investigating Conditions Needed Flashcards
1
Q
how do germinating seeds get a great deal of energy quickly?
A
- they use their food stores using enzymes that break down carbohydrate stores
- these are then used as a fuel in respiration to release energy
- this occurs until the leaves are in a position to photosynthesize
2
Q
in order to germinate what do plants need?
A
oxygen - to aerobically respire
warmth - optimum temperature for enzymes
water - to activate the enzymes
3
Q
the investigation of conditions needed for germination
A
- cress seeds are added to cotton wool in test tubes
- tube A is put in a fridge (no warmth) and the rest are kept on a windowsill
- in tube C, the cotton wool is moistened with boiled water and an oxygen absorber such as sodium pyrogallol is added (no oxygen)
- tube E is wrapped in foil (no light)
- the cotton wool in tube B is kept dry (no water)
- tube D has all the conditions present
- check for germination after 2-3 days - you could combine class results and calculate % germination or mean length of seed for each condition
4
Q
how can we tell if a seed has germinated?
A
it will have a shoot
5
Q
what different molecules do the seeds use as energy stores?
A
starch
6
Q
why is water needed for germination?
A
- water dissolves the minerals in the soil so they become available to the seed
- softens seed coating
7
Q
why is warmth needed for seed germination?
A
- speeds up enzymes which increases kinetic energy
- reactions are quicker
8
Q
why is light needed?
A
for photosynthesis
9
Q
why is oxygen needed?
A
for respiration
