B14 Hormonal coordination Flashcards
what is a negative feedback system
Negative feedback systems work to maintain a
steady state
what is Thyroxine
Controls basal metabolic rate in body
where is Thyroxine produced
Thyroid gland
what does the Thyroid gland use to produce Thyroxine
uses iodine
which organ monitors blood sugar levels
pancreas
what is insulin
hormone that reduces blood sugar concentration
what is glucagon
hormone that increases blood sugar concentration
what is type 1 diabetes caused by
genetics
what is type 2 diabetes caused by
obesity
lack of exercise
type 1 diabetes
Pancreas doesn’t make
enough or any insulin
Glucose high in blood so
kidneys filter it out
Lose weight as the body breaks down
protein and fat for energy
what could happen if type 1 diabetes wasn’t controlled
coma / death
type 2 diabetes
Pancreas makes less insulin
Cells stop responding to
insulin
what could happen if type 2 diabetes wasn’t controlled
coma / death
where is glycogen stored
liver and muscles
How do insulin and glucagon move around the body?
Through the blood
How can you test for diabetes?
and what results would it show
urine using Benedict’s solution
turn from blue to orange if there is glucose in the urine.
what is glycogen
stored carbohydrates in liver and muscles
what is glucose
blood sugar
why does urine not contain any protein or glucose?
glucose is reabsorbed in the kidney back to the bloodstream
protein is not filtered therefore stays in the body
What are the human body’s two communication systems?
Endocrine system
Nervous system
What makes up the endocrine system?
Glands
Name 6 glands that secrete hormones
Pituitary gland
Pancreas
Thyroid
Adrenal Gland
Ovary
Testes
What does the pituitary gland do?
‘MASTER GLAND’
~ Secrete hormones into the blood to either have an effect on the body or to prompt other glands to produce hormones
What does the thyroid do?
Secretes thyroxine
Controls metabolic rate, heart rate and body temperature
What is the purpose of the hormone thyroxine?
Controls how much energy your body uses, oxygen use, brain growth
What does the adrenal gland do?
Secretes adrenaline
Involved in ‘fight or flight’ situations
What does the ovary secrete?
Oestrogen
What is oestrogen involved in?
Menstruation
Puberty
Where is testosterone secreted?
Testes
What is testosterone involved in?
Puberty
What does adrenaline do?
-increases heart rate
-boost delivery of oxygen
and glucose to brain and
muscles to prepare for
‘fight or flight’
How does IVF Treatment work?
mother is given FSH and LH to stimulate maturation of several eggs
eggs collected from mother and are fertilised in a lab
eggs develop in to embryos
one or two eggs are inserted in to the mothers uterus when embryos are still a tiny ball of cells
What is the purpose of hormones in plants?
To coordinate and control their growth and their responses to light and gravity
What is phototropism?
Orientation and growth of plants in response to light
What is geotropism?
Growth of plants in response to gravity
What are plant hormones used in?
Used in agriculture and horticulture to control the growth of desirable plants and crops
What is the function of AUXIN?
Plant growth regulator
- Unequal distributions of auxin cause unequal growth rates in plant roots and shoots
What is the agricultural use of AUXIN?
-Weedkiller
-Rooting powder
-Promoting growth in
tissue cultures
What is the function of ethene?
(plants)
Acts as a hormone to control cell division
What is the agricultural use of ethene?
Control ripening of fruit during storage and transport
(e.g bananas)
What is the function of gibberellins?
Regulates developmental processes
e.g initiating seed germination
What is the agricultural use of gibberellins?
End seed dormancy
Promote flowering
Increase fruit size
Describe the process of kidney dialysis
Blood temporarily removed from patients body
Filtered through a dialysis machine
Patients blood is passed over dialysis fluid
Dialysis fluid has no urea, so urea and waste products diffuse in to the fluid
Blood is then returned in to the body
Which hormone controls water level in the blood
ADH
ADH, affects the amount if water absorbed by the kidney tubules
Why is the ammonia produced from excess amino acids converted in to urea?
Ammonia is very toxic
What is urea made out of?
Excess/ worn out protein
Where is urea produced?
Liver
What is in the blood going in to the kidneys?
RBC
Urea
Mineral salts
Glucose
Water
Large proteins
What is in urine?
Waste urea
Excess mineral ions
Excess water
Urobilin
What is urobilin made up from?
Breakdown in the haemoglobin in the liver
What happens if the water conc. in blood is too high?
~Pituitary gland releases less ADH
~Kidney tubules reabsorb less water
~Lots of urine is produced
What happens if the water conc. in blood is too low?
~Pituitary gland releases more ADH
~Kidney tubules reabsorb more water
~Little urine is produced
What can lead to kidney failure?
Genetic
Build up of toxins
Damaged by other means
What are the advantages of dialysis?
~No problem with tissue matching
~Machines are usually available
What are the disadvantages of dialysis?
~Has to happen at least twice a week for the
rest of life
~Expensive long term
Why must a person take immunosuppressants after having an organ transplant?
Otherwise the immune system will recognise that the organ is ‘foreign’ and will attempt to reject it
Why must body temperature be maintained?
To keep enzymes at an optimum temperature
Homeostasis
What can change body temperature?
Illness
Environment
Metabolism
Exercise
‘Fat’ around your body
Blood Loss
Why do we sweat when we get too hot?
As the sweat evaporates from the skin there is an increased energy transfer away from the body
Evaporation causes cooling
Why do we shiver when we are cold?
Move muscle fibres = respiration = heat
What causes shivering?
Skeletal muscles contract rapidly
(when we are cold)
where is FSH secreted
P. Gland
what is the role of FSH
-causes egg to mature in ovaries
-stimulates ovary to produce oestrogen
where is oestrogen secreted and made
made and secreted in ovaries
what is the role of oestrogen
causes lining of uterus to develop in preparation for pregnancy
what do high levels of oestrogen do?
inhibits release of FSH
stimulates release of LH
what is LH
luteinising hormone
where is LH secreted
P. Gland
what is the role of LH
stimulates the release of egg
(ovulation)
where is progesterone secreted
secreted by empty egg follicle
what is the role of progesterone
maintains lining of uterus in the second half of the cycle
inhibits release of FSH and LH
when do progesterone levels fall
when uterus lining sheds and period starts
what are the methods of hormonal contraception?
-oral contraceptives
(birth control)
-implant
-an injection
-skin patch
state the disadvantages of IVF
emotionally and physically stressful
low success rate
can lead to risky multiple births
