What are stimuli?
- Changes in the environment
What are inorganic molecules?
- Molecules that do not contain chains of carbon
- e.g. Water and mineral salts
What are 2 exceptions of inorganic molecules?
- CO2
2. CO
Why is water important?
- 70% living cells made up of water
2. Essential for life to exist
What 5 things is water important for?
- Water & metabolic reactions
- Water & transport
- Water & support
- Water & temperature control
- Water & protection
What is leaching?
- Washing out of minerals from soil
What is eutrophication?
- Process by which mineral nutrients accumulate in a freshwater body.
What are the basic functions of life?
- Movement
- Respiration
- Sensitivity
- Growth
- Reproduction
- Excretion
- Nutrition
- Death
Elements of protein
C H O N P Fe S
Monomer of protein
Amino acids
E.g. Glycine , alanine
Function of proteins
- Reserve energy source (after carbohydrates and lipids)
- Form antibodies
- Form hormones
- Make up 50% dry mass of cells
Structures and types of proteins
• 20 different kinds of amino acids
1. Dipeptide- 2 amino acids joined by a peptide bond
2. Tripeptide- 3 amino acids joined by a peptide bond
3. Polypeptide- short chain of amino acids
4. Protein molecule - chain of peptides
•amino acids linked by condensation reaction- release of water
• proteins broken down into amino acids through hydrolysis
• sensitive to extreme temps, pH levels
Million’s reagent test
- Place equal quantity of substance being tested with water into test tube.
- Add 1 ml of million’s reagent to test tube (be careful= poisonous)
- Heat test tube in a water bath containing boiling water
- Note the colour changes of the contents in the test tube
Biuret test
- Pour dilute NaOH (10ml) into test tube
- Add two drops of CuSO4 to solution
- Add substance being tested to test tube
