exercise and metabolism

• Metabolism

  SUM of all the CHEMICAL REACTIONS in an organism, which are regulated by ENZYMES.
• The energy transferred by RESPIRATION in cells is used by the organism for the continual ENZYME CONTROLLED processes of metabolism that create new molecules.
• ENZYMES are crucial as they control reactions, transforming SUBSTRATES into PRODUCTS.
• metabolic reactions:

  1.Multiple GLUCOSE molecules joining to form STARCH and CELLULOSE in plants, and GLYCOGEN in animals.

  2. Forming LIPIDS from ONE molecule of GLYCEROL and THREE molecules of FATTY ACIDS.

  3. Forming AMINO ACIDS by combining GLUCOSE with NITRATE IONS to produce PROTEINS.

  4. Breaking down GLUCOSE via RESPIRATION for TRANSFERRING ENERGY to power ALL reactions in the body.

  5. Breaking down EXCESS PROTEIN into UREA for EXCRETION.
• Exercise

  When you EXERCISE, your body undergoes changes to ensure enough ENERGY is supplied to your CELLS.
• Changes During Exercise:

  • MUSCLES contract more during exercise, requiring more ENERGY from increased RESPIRATION.
  • To supply OXYGEN for respiration, your BREATHING RATE, BREATH VOLUME and HEART RATE all increase.
  • If the exercise is VIGOROUS like sprinting, the elevated breathing and heart rate does not provide ENOUGH oxygen for aerobic respiration so ANAEROBIC RESPIRATION takes place.
  • This leads to MUSCLE FATIGUE and LACTIC ACID build up which causes the body pain and can lead to inefficiency in MUSCLE CONTRACTIONS due to fatigue.
• Anaerobic Respiration and Oxygen Debt

  • After the exercise is finished, your body has an OXYGEN DEBT that must be repaid to clear the LACTIC ACID that has built up.
  • To repay the OXYGEN DEBT, breathing and heart rate remains HIGH even AFTER stopping the exercise.
  • LACTIC ACID is transported to the LIVER to be converted back into GLUCOSE.