Paper 2

• What is homeostasis?

  Regulation of internal conditions despite external changes
• What are three internal conditions regulated by the body?

  Blood glucose concentration, temperature, water levels
• How does the nervous system help maintain homeostasis?

  By sending signals to effectors based on stimuli
• What does CNS stand for?

  Central Nervous System
• What is the role of receptors in the nervous system?

  To detect changes due to stimuli
• What is the difference between sensory neurons and motor neurons?

  Sensory neurons carry signals to the CNS, motor neurons carry signals away
• What is a reflex arc?

  A pathway where signals bypass the brain for quick responses
• What is the function of glands in the body?

  To produce specific chemicals as needed
• How can you investigate reaction times?

  By dropping a ruler and measuring the distance caught
• What is the effect of stimulants on reaction time?

  They can decrease reaction time
• What is the formula to calculate reaction time from distance?

  $S =$$\frac{1}{2} a t^2$
• What are the three parts of the brain?

  Cerebral cortex, cerebellum, medulla oblongata
• What does the cerebral cortex control?

  Higher level functions like memory and speech
• What is the role of the cerebellum?

  Controls motor skills, movement, balance, coordination
• What does the medulla oblongata control?

  Unconscious actions like heart and breathing rates
• What is MRI used for?

  To see brain activity safely
• What is accommodation in the eye?

  Ability to change lens shape for focusing
• What happens to the lens when focusing on distant objects?

  The lens becomes thin
• What is myopia?

  Shortsightedness, can't focus on far objects
• How do glasses help with hyperopia?

  By slightly converging or diverging light
• What is thermoregulation?

  Control of internal temperature by the brain
• What happens when the body is too hot?

  Sweat glands produce sweat to cool down
• What is vasodilation?

  Widening of blood vessels to increase heat loss
• What is the role of the endocrine system?

  To produce hormones that regulate body functions
• What is the main gland in the endocrine system?

  The pituitary gland
• What hormone does the pancreas produce?

  Insulin
• What happens when blood glucose levels are too high?

  The pancreas secretes insulin to lower levels
• What is type 1 diabetes?

  When the pancreas can't produce enough insulin
• What is type 2 diabetes?

  When cells no longer absorb glucose effectively
• What is the role of ADH?

  To regulate water reabsorption in kidneys
• What is negative feedback?

  Body's response to return conditions to normal
• What is the purpose of dialysis?

  To filter blood when kidneys aren't working
• What hormone is involved in menstruation?

  Follicle stimulating hormone (FSH)
• What does estrogen do during the menstrual cycle?

  Thickens the uterus lining
• What is the role of LH in menstruation?

  Causes the egg to be released
• What is contraception?

  Methods to prevent sperm from meeting egg
• What is IVF?

  In vitro fertilization, fertilizing eggs in a lab
• What does adrenaline do in stressful situations?

  Increases heart and breathing rates
• What is thyroxin's role?

  Controls metabolic rate in the body
• What do gibberellins do in plants?

  Promote seed germination and flowering