Homeostasis

• What happens to blood sugar levels after eating?

  They increase as you eat.
• What happens to blood sugar levels during exercise?

  They decrease as you exercise.
• Why is it important to control blood sugar levels?

  It interferes with osmosis.
• What occurs if blood sugar levels are too high?

  Water leaves cells, causing them to shrivel.
• What is homeostasis?

  • Regulation of internal environment
  • Maintains optimum conditions for function
  • Essential for life
• What conditions need to be controlled for homeostasis?

  • Blood sugar levels
  • Body temperature
  • Water levels
• What is the role of the nervous system in homeostasis?

  It sends electrical impulses to control levels.
• How does the endocrine system function in homeostasis?

  It uses chemical responses to control levels.
• What is the main difference between the nervous and endocrine systems?

  Nervous system is faster; endocrine is slower.
• What is a stimulus?

  A change in the environment.
• What is a response in the context of homeostasis?

  An action to counteract a detected change.
• What do receptors do?

  They detect stimuli.
• What is the role of the coordination center?

  It receives and processes information from receptors.
• What are effectors?

  Muscles or glands that bring about a response.
• Describe the process of homeostasis.

  1. Stimulus detected by receptors
  2. Information sent to coordination center
  3. Response initiated by effectors
  4. Optimum levels restored
• What is the function of mitochondria in cells?

  They provide energy for cellular functions.
• What is the purpose of shivering?

  To generate heat through muscle contraction.
• What is a reflex action?

  A rapid, automatic response of the nervous system.
• Why are reflex actions protective responses?

  They help avoid danger quickly.
• What are the three types of neurons?

  1. Sensory neurons: send impulses to coordination center
  2. Relay neurons: connect sensory and motor neurons
  3. Motor neurons: send impulses to effectors
• What is a synapse?

  A junction between two neurons.
• What is the difference between diffusion and osmosis?

  Osmosis is water movement; diffusion is particle movement.
• What does the cerebellum control?

  Muscular activity and balance.
• What is the role of the hypothalamus?

  It controls temperature and involuntary activities.
• What are the functions of the pituitary gland?

  • Controls hormone release
  • Regulates various body functions
• What is the role of the retina in the eye?

  Contains light-sensitive cells (rods and cones).
• What is the purpose of the pupil?

  It allows light to enter the eye.
• What is the sclera?

  White outer layer of the eye.
• How does the ciliary muscle function?

  It changes the shape of the lens.
• What are the problems associated with the eye?

  • Vision impairment
  • Eye diseases
  • Need for corrective lenses
• What is the role of the optic nerve?

  It sends visual information to the brain.
• What does the bouncy layer of the eye contain?

  Light sensitive rods and cones
• What is the function of the white outer layer of the eye?

  It is tough and strong to prevent damage
• What is sent to the brain from the eye?

  Nerve signals
• What is homeostasis?

  Regulation of internal environment for optimal function
• What are the three controlled conditions in homeostasis?

  • Blood glucose levels
  • Water levels
  • Internal body temperature
• What is the purpose of a reflex action?

  To protect the body from danger
• What is a synapse?

  Junction between two neurons
• What are the components involved in a reflex action?

  • Sensory neurone
  • Motor neurone
  • Spinal cord or coordination centre
• What is a stimulus in the context of reflex actions?

  It is the trigger for a reflex response