For energy, provide raw materials to build and repair cells and to control chemical reactions
Definitions
Biomolecules
Biomolecules are organic molecules such as proteins, nucleic acids, carbohydrates, and lipids that are essential to the functioning and growth of living organisms.
Nutrients
Nutrients are substances obtained from the diet that are used by organisms to support growth, reproduction, and health maintenance. They include carbohydrates, proteins, fats, vitamins, and minerals.
Metabolism
Metabolism is the sum of all the chemical reactions in an organism
Trace Element
Needed in only tiny amounts in an organism e.g. Cu and Zn. Dissolved salts e.g. sodium (Na) or Magnesium (Mg)
Deamination
Excess amino acids are brought to the liver ad converted to urea which is carried by the blood to the kidney and removed as urine
Function of Food
Carbohydrates
Carbohydrates are primary energy sources for many organisms. Contain the elements C, H & O. General formula Cx(H2O)y. Structurally, they can be classified into monosaccharides (glucose), disaccharides (sucrose) and polysaccharides (glycogen). Structural role: cellulose in plant cell wall. Metabolic role: provide energy
Protein
Proteins are made up of amino acids, which are organic compounds that combine to form proteins. They play a crucial role in cell function and structure, acting as enzymes, and supporting immune responses. Contain the elements C, H, O & N. Structurally, they can be classified as peptides (<20aa), polypeptides (>20aa) or protein (at least 200aa). Structural role: keratin in hair. Metabolic role: make enzymes.
Fibrous protein: little folding e.g. keratin. Globular protein: a lot of folding e.g. egg white.
Lipids
Fats are solid at room temperature and oils are liquid at room temperature. Contain the elements C, H & O. Triglyceride: glycerol backbone attached to three fatty acids. Phospholipid: Glycerol backbone attached to two fatty acids and a phosphate. Structural role: cell membrane. Metabolic role: release energy.
Vitamins
Vitamins are organic molecules necessary for normal metabolism, important for maintaining health and preventing diseases.
Water soluble: Vitamin C: found in fruit and vegetables - used to make connective tissue - deficiency: scurvy
Fat soluble: Vitamin D: found in milk - made by skin - needed to absorb calcium into bones - deficiency: rickets/ osteoporosis
Minerals
Minerals are inorganic nutrients that play critical roles in bone health, nerve function, and blood production.
Plant: Calcium (Ca): absorbed from soil - binds cell walls - deficiency: poor growth
Animals: Iron (Fe): milk, cheese - form bones and teeth - deficiency: anaemia
Water
Water is a universal solvent, it absorbs heat energy, allows for chemical reactions to take place and transports a range of materials like minerals, amino acid and hormones