Events In Germination Flashcards
How do seeds store food?
They store food in the form of oils, starch (especially in cereals and grasses) and protein (especially in legumes such as peas and beans)
Give some examples of seeds which store food as starch.
Cereals
Grasses
Give some examples of seeds which store food as protein
Legumes such as peas and beans
When does germination begin?
(Step 1)
(3)
Germination begins when the seed absorbs water
Water is absorbed through a tiny hole called the micropyle and through the testa
Water allows enzymes to be activated in the seed
How exactly does the seed absorb water?
It is absorbed through a tiny hole called the micropyle and through the testa
Explain how seeds digest food.
(Step 2)
(4)
In germinating seeds;
- oils are digested to fatty acids and glycerol
- starch is digested to glucose (involves the enzyme amylase)
- proteins are digested to amino acids
What are oils broken down into in seeds?
Oils are digested to fatty acids and glycerol
What is starch broken down into in seeds?
Starch is digested to glucose
What enzyme is involved in the breakdown of starch into glucose?
Amylase
What are proteins broken down into in seeds?
Proteins are digested into amino acids
What happens to the products of digestion in seeds?
Step 3
The products of digestion are moved to the growing embryo (i.e. the plumule and radicle)
What happens to glucose and amino acids in seeds?
Step 4
Glucose and amino acids are used to make new structures such as cell walls and enzymes
What happens to fats and some of the glucose in seeds?
Step 5
The fats and some of the glucose are used in respiration to produce energy
What happens to the seed after respiration has occurred?
Step 6
The dry weight (mass) of the seed falls due to the foods used in respiration
What happens to the embryo after the weight of the food stores falls?
(Step 7)
As the weight of the food stores (i.e. the endosperm and/or the cotyledon(s)) the weight of the embryo increases
