CCEA GCSE BIOLOGY unit 1 notes
UNIT 1: Photosynthesis
Photosynthesis Word Equation:
Carbon Dioxide + Water Oxygen + Glucose
How to test a leaf for starch:
1. Dip leaf boiling water for about 1 minute to soften it, stop further chemical changes and make the cell more permeable.
2. Turn off Bunsen burner.
Put the leaf into the half a test-tube of ethanol.
Stand the test-tube in the hot water for a few minutes.
(Takes green chlorophyll out of leaf)
3. Dip the leaf into water. (Softens the leaf)
4. Spread the leaf out on a white tile and cover it with iodine …show more content…
A poorly balanced diet or obesity can lead to Type 2 diabetes.
The body suffers sugar ‘overload’ and insulin stops being effective in controlling the sugar levels.
Digestion is the breakdown of large insoluble molecules into small, soluble food molecules so that they can be absorbed into the bloodstream
Starch Amylase Glucose
Protein Protease Amino Acids
Fats Lipase Fatty Acids & Glycerol
Parts of body, and functions with in digestion system:
Buccal Cavity- food is mixed with saliva, saliva contains the enzyme amylase.
Tongue- tastes and moves the food around.
Teeth- chew the food.
Epiglottis- Prevents food from getting to the lungs.
Oesophagus- Tube that connects the mouth and stomach. Has circular muscles in its wall which contract and squeeze in behind the food. This is called peristalsis.
Stomach- churns the food, mixing it with hydrochloric acid and gastric juices. Gastric juices contain protease which begins protein digestion.
Pyloric Sphincter- A ring of muscle that keeps food inside the