Hormonal Coordination A Flashcards
What is the human endocrine system?
Comprises glands that secrete hormones into the bloodstream.
What is different about the HES compared to the nervous system?
The effects of the HES are slower but last for longer.
What is does the pituitary gland do and why is this important?
Secrete several hormones - act on other glands to stimulate the release of other hormones, which brings about an effect.
What organ monitors blood glucose levels?
The pancreas.
What sort of ‘feedback’ control is the control of blood sugar levels?
Negative.
How is the control of blood sugar levels an example of negative feedback?
The pancreas switches production between insulin and glucagon to control blood glucose levels.
What is negative feedback?
A mechanism where changes to conditions cause an action to reverse the change, to keep conditions stable.
What happens with diabetes?
The body can either not produce enough or respond to insulin. It leads to uncontrolled blood glucose concentrations.
What are 2 differences between Type 1 and Type 2 diabetes?
- T1 - early onset, T2 later onset - obesity a risk factor.
- T1 - pancreas does not PRODUCE sufficient insulin, T2 - body does not RESPOND to insulin
- T1 - treated through injections + diet and exercise, T2 - treated through a carbon-controlled diet and exercise
What is lost from the skin in sweat?
Water, ions, urea
How are excess water, ions and urea removed?
In urine.
How do the kidneys produce urine?
Filtration of the blood and selective reabsorption of useful substances such as water, glucose and some ions.
What hormone controls water levels?
ADH
What does ADH do specifically?
Controls the amount of water absorbed by the kidney tubules
What type of cycle is the regulation of water levels?
Negative feedback.
What is kidney dialysis used for?
To treat people with kidney failure.
Fill in the blanks: The digestion of ________ from food results in excess _____ _____, which need to be ________ safely.
These are _________ in the liver to form _______.
- Proteins
- Amino acids
- Excreted
- Deaminated
- Ammonia
True or false: ammonia is safe.
False. Ammonia is toxic so is immediately converted to urea for safe excretion.
What is produced by the adrenal gland and what does it do?
Adrenaline - produced in times of fear or stress -> increases heart rate, boost delivery of oxygen and glucose to brain and muscles, prepares body for ‘fight or flight’ response
What is produced by the thyroid gland and what does it do?
Thyroxine - controls metabolic rate, important for growth and development
True or false: both thyroxine and adrenaline production is controlled by negative feedback.
False - adrenaline is NOT controlled by negative feedback. Thyroxine is.
What is released when the blood glucose level is too low?
Glucagon
What is released when the blood glucose levels are too high?
Insulin
What is glycogen converted into? (low blood glucose)
Glucose
What organ releases glucagon and insulin?
Pancreas
What is excess glucose converted into? (high blood glucose level)
Glycogen
When blood sugar is too high, what organ converts excess glucose into glycogen?
Liver (or muscle cells for storage)
When blood glucose levels are high, where does glucose move from and to?
Glucose moves from blood into cells
Explain the process that takes place when blood glucose levels are too low. (4 steps)
- Pancreas releases the hormone glucagon
- Glycogen is converted into glucose and released into blood
- Amino acids and fats are broken down by these
- Blood glucose rises so becomes a normal level again
What organ monitors and controls blood glucose levels?
Pancreas
Explain the process that takes place when blood glucose levels are too high. (4 steps)
- The pancreas releases insulin into the bloodstream
- Insulin stimulates the liver to convert glucose into glycogen and it causes cells to take up glucose
- This decreases the concentration of glucose back to normal levels
