Chapter 11 Excretion Lesson 1 - Introduction to Excretion
- 1. Chapter 11
- 2. Chapter 11 Excretion Learning Objectives: Define excretion as the removal of toxic materials and the waste products of metabolism from organisms. Describe the removal of carbon dioxide from the lungs.
- 3. Chapter 11 Excretion Learning Objectives: Identify on diagrams and name: kidneys, bladder, urethra; and state the function of each. Describe dialysis in kidney machines as the diffusion of waste products and salts (small molecules) through a membrane – large molecules (e.g. protein) remain in the blood.
- 4. Chapter 11 Excretion Please write down on the piece of paper what do you think are the products of excretion? Answer : Main waste products are carbon dioxide, urea, excess water & excess heat. NOT FAECES !!
- 5. Chapter 11 Excretion Excretion is the removal of toxic materials and the waste products of metabolism from the body. Egestion is the removal of undigested food matter which have never been involved in the metabolic activities of cells, from the alimentary canal. faeces
- 6. Metabolism = Anabolism + Catabolism Anabolism : The building up of complex substances from simpler ones with an intake of energy
- 7. Example of Anabolism: Synthesis of glycogen from glucose (Chapter 4 pg 57) Glycogen Glucose molecules
- 8. Catabolism : The breakdown of complex substances into simpler substances with the release of energy. Examples: Tissue respiration (chpt 10, pg 195) C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + Energy enzymes
- 9. 2) Breakdown of excess amino acids to urea (Deamination) (chpt 6 pg 108) (toxic to cells) urea in urine) amino group ammonia (non toxic,excreted R deamination carbon residue glucose glycogen (stored in liver and muscles) NH 2 -CH-COOH
- 10. Metabolism…. Metabolism produces waste products When present in high concentration… WASTE PRODUCTS Therefore, waste products must be excreted from the body become TOXIC!!
- 11. Excretory Organs in Man Skin (chpt 12) Lungs (chpt 10) Kidneys (chpt 11) Liver (chpt 6)
- 12. Excretory Products in Man Carbon Dioxide Excess Water excreted mainly via excreted mainly via also thru’ &
- 13. Excretory Products in Man 3) Urea 4) Excess Heat excreted mainly via excreted mainly via
- 14. Excretory Products in Man 5) Bile Pigments are produced by the breakdown of haemoglobin in Excreted in the faeces