Chapter 3 Metabolism

• metabolism


  chemical reactions that take place in cells and in organism of which cells are part of
• types of metabolism


  catabolism

  anabolism
• catabolism


  reactions in which large molecules are broken down to smaller ones, release energy

  digestion
• anabolsim


  reactions in which small molecules are built up into larger ices, require energy

  protein synthesis
• metabolism is concerned with

  maintaining balance between energy release and energy utilisation
• nutrients


  any substance in food that is ed for growth, repair or maintaining the body

  required for metabolism
• six groups of nutrients

  water

  carbohydrates

  lipids

  proteins

  minerals

  vitamins
• inorganic compounds


  not based in carbon chains most do not contain carbon atoms

  those that do are small molecules
• important inorganic compounds


  water

  minerals

  vitamins
• water (metabolism)


  important as the fluid where other substances are dissolved

  some cells chemical reactions occur in water
• minerals (metabolism)


  part of enzymes

  function as cofactors

  part of substances such as ATP
• vitamins (metabolism)


  act as coenzymes
• organic compounds


  molecules that have carbon chain

  contain number of hydrogen atoms
• carbohydrates


  main source of energy for cells

  carbon, hydrogen and oxygen atoms
• simple sugars (glucose) used in cellular respiration to:

  release energy
• complex carbohydrates (starch) are broken down to:


  simple sugars
• monosaccharides


  simple sugars

  glucose, fructose, galactose
• disaccharides


  formed when simple sugars join together to form larger molecules

  sucrose, maltose, lactose
• polysaccharides


  larger carbohydrate molecules formed when many simple sugars join together

  glycogen, cellulose, starch
• lipids


  fats and oil

  important energy source
• lipids broken down to

  fatty acids and glycerol
• glycerol can enter:


  glycolysis pathway of cellular respiration then broken down to release energy
• phospholipids


  important in cell membrane and steroids like cholesterol and sex hormones
• each lipid molecule consists of


  one molecule of glycerol and 1,2 or 3 fatty acid molecules
• triglyceride


  most common fat

  found in fat stored in body

  composed of glycerol and 3 fatty acids
• proteins are made up of

  many amino acids
• for metabolism most important protein is

  enzymes
• enzymes influence metabolism by

  controlling chemical reactions that occur in the body
• proteins also be used as

  source of energy but only if supply of carbohydrates and lipids is inadequate
• amino acid


  molecule containing both amino group and carboxylic acid group

  20 different in proteins each differing in structure of side chain
• peptide bond


  two amino acids bonded together and react to form it, releasing water molecule when it forms peptide bond
• proteins consist of (how many amino acids)

  100+ amino acids

  type and order based on DNA that codes for protein production
• each protein has characteristic shape due to

  the folding of chain
• dipeptides


  shorter lengths of amino acids

  two or more amino acids joined
• polypeptides


  made up of more than 10 amino acids
• nucleic acids


  ribonucleic acid RNA and deoxyribonucleic acid DNA
• DNA consists


  two chains of nucleotides that contain sugar deoxyribonucleic
• genetic material in nucleus stores

  inherited information
• RNA made up of

  single strand of nucleotides contains sugar ribose
• RNA carries


  information from DNA in nucleus to ribosomes for protein production