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• Photosynthesis is going to take water, carbon dioxide, and turn it into oxygen and glucose
• Light


  Not a reactant in photosynthesis, but a condition that's needed
• Photosynthesis formula


  H2O + CO2 → O2 + C6H12O6
• Photosynthesis


  An endothermic reaction that takes in energy
• Requirements for photosynthesis


  • Chlorophyll
  • Water
  • Carbon dioxide
  • Sunlight
• Percentage level of carbon dioxide increases

  Rate of photosynthesis increases (up to a point)
• Percentage level of water increases

  Rate of photosynthesis increases (up to a point)
• Temperature increases


  Rate of photosynthesis increases (up to an optimal point)
• Temperature continues to increase past optimal point


  Rate of photosynthesis decreases as enzymes are denatured
• Light intensity increases


  Rate of photosynthesis increases (up to a point)
• Even when the graph is flat, there is still a steady rate of photosynthesis
• The actual rate of photosynthesis depends on many different factors
• Starch


  The glucose from photosynthesis is stored as starch, with potatoes being an obvious example
• Leaf structure


  • Palisade mesophyll (photosynthesis)
  • Cuticle (waxy layer)
  • Upper and lower epidermis
  • Spongy mesophyll (gas exchange)
  • Guard cells and stomata (transpiration)
• Xylem


  Carries water upwards from roots to leaves
• Phloem


  Carries ions and food downwards from leaves to roots
• Factors affecting rate of transpiration

  • Bright light
  • High temperature
  • High wind
  • Low humidity
• Parts of the endocrine system

  • Pituitary gland
  • Thyroid
  • Adrenal glands
  • Pancreas
  • Ovaries
  • Testes
• Testosterone


  Produced by testes, has effects of growing muscles, making balls and penis grow, increasing hair growth
• Estrogen


  Produced in ovaries, responsible for maturation of eggs and menstrual cycle
• Insulin


  Produced by pancreas, important for regulating blood glucose levels
• Adrenalin


  Produced by adrenal glands, part of fight or flight response
• Thyroxine


  Produced by thyroid, important in regulating metabolism
• Follicle stimulating hormone (FSH)


  Produced by pituitary gland, makes small egg grow to larger egg
• Luteinizing hormone (LH)


  Produced by pituitary gland, job is to release the egg
• Progesterone


  Builds up slowly to build up lining of uterus
• Methods of contraception


  • Condom (barrier)
  • Pill (hormonal)
  • Coil/IUD (hormonal)
  • Diaphragm (barrier)
  • Sterilization (permanent)
• Around one in six people can't have children naturally, with half due to male reasons and half due to female reasons
• IVF


  Involves taking many drugs with nasty side effects, is very expensive, and has a 40% success rate
• Homeostasis is the maintenance of a constant internal environment
• Things homeostasis controls


  • Blood glucose levels
  • Water levels
  • Temperature
• Brain


  The control center for homeostasis, sending signals to various parts of the body
• Control of blood glucose

  1. Blood glucose rises after a meal

  2. Pancreas produces insulin

  3. Insulin causes body cells to remove glucose from blood

  4. Blood glucose falls

  5. If blood glucose gets too low, pancreas produces glucagon

  6. Stored glycogen is converted to glucose and returned to blood

  7. Blood glucose rises again
• Type 1 diabetes


  Pancreas doesn't produce enough insulin
• Type 2 diabetes


  Cells become insensitive to insulin
• Symptoms of diabetes


  • Loss of weight
  • Increased need to urinate
  • Thirst
  • Blurry vision
  • Fatigue
  • Hunger
• Diffusion


  Movement of things from high concentration to low concentration down a concentration gradient
• Glycogen


  Stored form of glucose in muscle and liver cells
• Glucagon converting glycogen into glucose


  Causes blood glucose levels to rise again
• Type 1 diabetes


  Pancreas doesn't produce the right amount of insulin