Hormonal Co-ordination in Animals - The Endocrine System + Kidneys + Kidney Treatments+ Flashcards
What is the endocrine system and what does it do?
- made of glands
- secretes hormones into bloodstream
- blood carries hormone to the target organ
- effects are slower, longer lasting compared to nervous system
What are hormones and what is their function?
- hormones are chemical molecules released directly into the blood
- are carried in the blood to other parts of the body, only effect particular cells in particular organs - target organs
- hormones control things in organs and cells that need constant adjustment
where are hormones produced?
produced and secreted by various glands, called endocrine glands
hormones have short/long lasting effects?
long
name 6 examples of glands within the human body:
- the pituitary gland
- ovaries - females only
- testes - male only
- thyroid
- adrenal gland
- pancreas
what is the function of the pituitary gland?
- produces many hormones that regulate body conditions
- hormones act on other glands–> directing them to release hormones that bring about change
what is the function of the testes?
- produces testosterone –> controls puberty + sperm production in males
what is the function of the ovaries?
- produces **oestrogen –> involved in the menstrual cycle
what is the function of the thyroid?
- produces thyroxine –> regulates things like :
- rate of metabolism
- heart rate
- body temperature
what is the function of the adrenal gland?
- produced adrenaline
- used to prepare the body for ‘flight or fight’ response
what is the function of the pancreas?
- produces insulin –> regulates blood glucose level
what are the differences between hormones and nerves?
NERVES:
- very fast reaction
- act for a very short time
- act on a very precise area
HORMONES:
- slower action
- acts for a long time
- acts in a more general way
what is blood glucose controlled by?
- homeostasis
- insulin and glycagon are the 2 hormones involved
What is the pancreas role in maintaining the blood glucose levels
- pancreas continuously monitors blood glucose levels
- Produces 2 hormones involved into regulation:
- insulin
- glucagon
- secreted into the blood stream
- travel in blood to their target organs (the liver) where response occurs
When blood glucose levels are too high what hormone is secreted, the process and what are the effects?
- pancreas secretes insulin
- Effect on Liver : insulin makes
liver converts glucose to glycogen, and stored in liver and skeletal muscles - Effect on glucose levels: goes down as glucose is removed from blood
When blood glucose levels are too low what hormone is secreted and what are the effects
- pancreas secretes glucagon
- glucagon makes liver converts glycogen —> glucose
- glucose levels increase as it is released into blood from the liver cells
The blood glucose level is kept constant by a n………….. f……………… m…………….
Negative feedback mechanism
What is negative feedback ?
- when the internal factor rises above the normal level, the body responds by lowering the factor
- vice versa when the internal factor is below the normal level
What is the kidney’s main function
To maintain the water balance of the body
- excess water, excess ions and urea are removed via the kidneys in the urine
The kidney is a specialised organ in which body system
Urinary system
How is water taken into the body?
ingesting food and drinks
What are the 2 ways water can leave the body?
- Exhalation
- Sweat
What substances are lost in sweat
- water
- ions
- urea
What happens during the filtration process?
- kidneys make urine by taking waste products out of your blood.
- substances are filtered out of the blood as it passes through the kidneys
What is selective re-absorption?
- useful substances like glucose, some ions and the right amount of water are absorbed back into the blood after the kidney filtrates unwanted substances out
How is Urea excreted from the body:
- ** Excess proteins and amino acids** cant be stored in the body — a process called deamination in the liver converts some amino acid into fats and carbohydrates, which can be stored
- ammonia is produced as a waste product
- ammonia is toxic so its converted to urea in the liver. Then transported to the kidneys, where its filtered out of blood and excreted from body in urine