2.2 biology

• Nervous system


  The Central Nervous System (CNS) and the nerves
• Central nervous system (CNS)


  The brain and the spinal cord
• Cerebrum


  Part of the brain responsible for conscious thought, memory and personality
• Cerebellum


  The part of the brain responsible for balance and coordination
• Medulla


  The part of the brain responsible for controlling heart rate and breathing rate
• Sensory neuron


  Carries impulses signal from sense organ to the inter neuron (spinal cord)
• Inter neuron


  Carries impulses from sensory to the motor neuron within CNS
• Motor neuron


  Carries impulses from the inter neuron to the muscle or organ
• Electrical impulses


  How messages are passed along neurons
• Chemicals


  How messages are passed through a synapse
• Synapse


  The gap between two neurons
• Receptor protein


  The proteins that detect an external stimulus
• Stimulus


  An external factor that can cause a response in the body (e.g. light, taste, sound, etc.)
• Effectors


  Carries out the response to a stimulus (e.g. muscle or gland)
• Reflex arc


  Rapid, automatic and protective response to protect the body from harm
• Endocrine gland


  Gland that produces hormones
• Hormones


  Chemical messengers that travel in the blood
• Target tissue


  Target tissue that has cells with complementary receptor proteins, so only that tissue will be affected by those hormones
• Receptors


  Protein found on target cells of hormones. They are complementary to hormones
• Liver


  Target tissue of insulin and glucagon. It stores excess glucose as glycogen
• Pancreas


  Organ that detects changes in blood glucose levels. It produces insulin and glucagon
• Insulin


  Hormone that is made when blood glucose increases. It lowers blood glucose by promoting the liver to convert glucose into glycogen
• Glucagon


  Hormone that is made when blood glucose decreases. It raises blood glucose by promoting the liver to convert glycogen back into glucose
• Glycogen


  Storage carbohydrate found in the liver
• Blood


  How hormones travel in the body
• when is insulin produced

  when blood glucose levels increase