Seeds Flashcards
What are seeds adapted to?
protect embryo, aid dispersal and provide nutrition for the new plant
Define gelatinisation
starch granules are heated in water and suddenly well and absorb water to thicken the liquid (custard and wallpaper paste)
Why is starch easily extracted?
In granules which don’t dissolve in water but can be washed out
Describe starch foam
water contents of less than 10% gelatinisation occurs at high temp if pressure is raised the starch “puff”, used in cooking
Describe super absorbent
starch is chemically cross linked before gelatinisation then particles are formed that can be dried when rehydrated they take up large amounts of water
What happens when the ovules fertilised
Outer layers become lifnigfied forming a tough seed coat that protects the embryo in the seed
Whats endosperm?
storage tissue where foods stored outside embryo, found in stem or stalk
Describe the enzymes that break starch and proteins
Maltase and amylase break the starch into glucose converted to sucrose for transport to the radicle and plumule
Protese breaks down proteins in food store into amino acids
Lipase breaks down lipids into glycerol and fatty acids
Describe seed dispersal
Appropriate for wide dispersal helping off spring to avoid competing with parents
One method dispersal - wind, animal, water or self dispersal
How is water taken up?
When dormancy has been broken, water is taken through a small pore in the seed coat
Describe sustainability?
Fuel made of veg oil produces co2 which has been removed when the crop that produced it was grown
Paper bags - end up on ground when wet and transport heaviers bags uses more fuel
Plant bags remain intact, light, biodegrade
Most bacteria need o2 so if deeply buried they don’t biodegrade
not guaranteed by switching to products made by plants
