Biology - Homeostasis

• Defintion of homeostasis

  The regulation of optimal conditions of a cell or organism in response to internal or external changes.
• Defintion of vasodilation

  The widening of blood vessels
• Definition of vasoconstriction

  Constriction of blood vessels
• Define negative feedback

  Receptors detect change for the effectors to counteract the change to bring conditions back to optimul levels
• Define refelx actions

  Automatic responses to protect the body that bypass the brain
• Describe what happens in someone's body when having type 2 diabeties

  • Liver doesn't respong to insulin
  • Pancreas secreates enough insulin
  • Glucose can't be stored as glycogen
• What happens when you have a low blood glucose level with type 2 diabeties

  • Blood glucose levels decreases
  • Pancreas produces glucagon
  • The liver turns the glycogen into glucose
  • Normalised blood glucose levels
• Risk factors of type 2 diabeties

  • Diet high in carbs
  • Obesity
  • Lack of exercise
• Treatments for type 2 diabeties

  • Carb contrlled diet
  • Exercise
• How do people get type 1 diabeties

  Genetics
• What happens to the body with someone who has type 1 diabeties

  • The pancreas doesnt produce enough insulin
  • Results in high blood glucose concentration
• Treatments for type 1 diabeties

  Insulin injections
• What happens when a persn with type 1 diabeties have a high blood gluocse concentration

  • Have a high blood glucose concentration
  • Pancreas produces insulin
  • Liver converts glucose into glycogen
  • Normalised blood glucose levels
• Name all the glands

  • Pituitary gland (master gland )
  • Thyroid gland
  • Adrenal gland
  • Pancreas
  • Ovaries
  • Testes
• Name all the hormones from the glands

  • Thyroxine
  • Adrenalin
  • Oestrogen
  • Testosterone
  • Insulin + Glucogon
• What does the pituitary gland do

  Secreates hormones to stimulate other glands to also produce hormones
• What does the thyroid gland do

  • Produces thryroxine which increases metabolism
  • Controls growth and developtment
  • Controlled by negative feedback
• What does the adrenal gland do

  • Produces adrenalin when sacred or stressted
  • Prepares the body for fight or flight
  • Increases heart rate so more oxygen is delivered to your muscles
  • Increases blood glucose concentration to muscles to respire more and have more energy
• What do the ovaries do

  • Produce oestrogen
  • Plays a role in reproduction, the menstrual cycle and puberty
• What do the testes do

  • Produce testosterone
  • PLays a role in reproduction, growth and puberty
• What does the pancreas do

  • Prodcues insulin when BGC is high
  • Produce glucogon when BGC is low
  • Insulin causes the excess glucose to go to your liver and convert it to glycogon
  • Negative feedback controls BGC
• What neurons (in order) are inbetween the recptor and effector

  • Sensory neuron
  • Relay neuron
  • Motor neuron
• Explain the steps of the required practical - Reaction time

  • Experimenter holds ruler from the end
  • The subject has their hand at the 50cm line around the ruler
  • Experimneter lets go of the ruler
  • Subject tries grab the ruler as quickly as possible
  • Write down the distance from the 50cm line
  • Repeat until there is enough for aon accurate enough mean
• Ruler drop test negatives

  • Repeating same actions can speed up your recation time = unfair results
  • Amount of sleep the previous night
  • Distractions in the room
  • Amount of food eaten previously
  • Caffine beforehand
• What is the nervous system

  It enables humans to react to their surroundings and coordinate their behavier
• What is the endocrine system?

  System of glands that secrete hormones
• What are hormones?

  Chemical messengers transported in the blood
• What is a cause of Type 1 diabetes?

  Genetics
• What causes Type 2 diabetes?

  Pancreas doesn't produce enough insulin
• What is a common treatment for diabetes?

  Insulin injections
• What results from high blood glucose concentration?

  It can lead to diabetes complications
• What factors contribute to Type 2 diabetes?

  High carb diet, obesity, lack of exercise
• What is glycogen?

  Storage molecule for glucose in cells
• What is glucagon's role in the body?

  Raises blood glucose levels
• What is homeostasis?

  Regulation of internal conditions in organisms
• What is vasodilation?

  Widening of blood vessels
• What is vasoconstriction?

  Constriction of blood vessels
• What is negative feedback?

  Receptors detect change and counteract it
• What do thermoreceptors detect?

  Changes in temperature
• What is the role of the coordination center?

  Processes information from receptors