B1 Topic 2 Homeostasis Flashcards
Definition of osmoregulation
The control of water in your body
What is glucose control?
It controls how much insulin or glucagon you have
What does glucagon do?
Glucagon causes the liver to convert stored glycogen into glucose
Definition of homeostasis
The regulation of your internal environment
How do we lose water?
Sweating
Urinating
Breathing
What happens if you have too much water?
The kidneys produce more urine
What happens if you have too little water?
Your kidneys don’t produce urine, brain makes you feel thirsty
What is temperature controlled by in the brain?
The Hyptohalamus
What is thermoregulation an example of?
Negative feedback
What is negative feedback?
Where our body does the opposite to what it is feeling
What is the reflex arc?
A nerve pathway
What is the prompt to remember the reflex arc?
Smelly Rectum Smelly Smelly Rectum Smelly Men Eat Rectum
What order is the reflex arc?
Stimuli Receptor Sensory neurone Synapse Relay neurone Synapse Motor neurone Effector Response
What is a synapse?
A junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.
Electric-chemical-electric
Explain how a Type 2 diabetic can regulate their blood glucose concentration
Taking medication, including insulin
Exercise
Healthy diet
what is excess blood glucose converted into?
Glycogen in the liver
Explain how a Type 2 diabetic can regulate their blood glucose concentration
Taking medication, including insulin
Exercise
Healthy diet
What temperature do enzymes work best at?
37 degrees
Explain how the human body maintains a stable internal temperature when the
external temperature is 0 °C.
Hypothalamus detects temperature drop
Hairs on the skin trap more warmth if they are standing up
Your body shivers, friction= heat
Vaso-constriction - no blood flowing at surface
Sweat glands close, no further heat loss
Hypothalamus detects increase in temperature
Describe one way in which the skin helps in the control of body temperature.
Sweat glands release water, which evaporates and takes the heat energy with it which cools the surface of the skin.
Erector muscles in the skin contract, causes the hair to trap heat
Explain why humans need to maintain their body temperature at 37°C.
in order for the enzymes to be most effective / best /optimum temperature for enzymes to work
for chemical reactions to happen
at too high temperatures enzymes are denatured, at colder temperatures enzymes are less active
What is vasodilation?
Where your blood vessels widen, more warm blood flows near the surface.
What is Vasoconstriction?
Where your blood vessels are narrowed, less blood flows near the surface of the skin
Explain how thermoregulation causes this reduction in body temperature.
The Hypothalamus in the brain controls temperature
The body sweats more, the sweat evaporates taking the heat with it
Vasodilation of blood vessels
Heat lost by radiation
This is called negative feedback
Explain how exercise can cause body temperature to increase.
Muscles contract and relax, this causes friction which releases heat by respiration
Receptor cells in the skin detect temperature changes in the external
environment.
Explain how this information is transmitted to the brain.
(travel along) sensory neurones as electrical / electric impulses across synapses (gap between two neurones) using neurotransmitters reference to spinal cord
What is the benefit of the myelin sheath?
It speeds up the signal
Insulates the nerves
Describe what happens when your blood glucose levels are too high?
Pancreas releases insulin
Insulin travels to the liver
Tells liver to convert excess glucose into glycogen
Glucose levels return to normal
Describe what happens when your blood glucose levels are too low?
Pancreas releases glucagon
Glucagon travels to the liver
Tells the liver to turn glycogen into glucose
Glucose levels return to normal
What is insulin and glucagon an example of?
Hormone
What happens if your blood glucose levels are too high?
Pancreas releases insulin
Insulin travels to the liver
Insulin causes the liver to turn excess glucose into glycogen
Glucose levels return to normal
What happens if your blood glucose levels are too low?
Pancreas releases glucagon
Glucagon causes the liver to convert excess glycogen into glucose
Glucose levels return to normal
