B11-hormonal control Flashcards
What does the hormonal system do
are chemical messengers from glands
they generate a response by regulation by homeostasis and other processes
-their effect is they travel to the target organ in the bloodstream and bind to receptors on the surface of organs (slower than nervous system! But longer lasting)
-e.g. insulin, ADH, adrenaline, thyroxin, cortisol, testosterone, oestrogen
What are hormones
They are chemical messengers from the glands
What are target hormones
Where the hormones produce an effect and have receptors on the cell membrane that pick up the hormone molecules triggering a response in the cell
What is type 1 diabetes
It is when your pancreas doesn’t make enough or any insulin your blood glucose concentration is not controlled. Which caused various problems when eating and with weight and tiredness.
What causes type 1 diabetes
There seems to be a genetic element to development of the disease usually starting in young children and teenagers.
Treatment of type 1 diabetes
You have to inject insulin as replacement insulin before meals every day and it is successful but it does not cure it and there is no cure yet. Also you need to be careful about the levels of carbohydrates you eat, regular meals and exercise but it needs to be carefully planned to keep your blood glucose levels steady. There are possible cures for type 1 diabetes from pancreatic transplants and maybe embryonic stem cells
What is type 2 diabetes
The pancreas still makes insulin but it may make less than your body needs and your body cells stop responding properly to the insulin made.
What causes type 2 diabetes
A very common diabetese and gets more common as you get older and is often linked to obesity lack of exercise or both and there is a strong genetic tendency to develop it.
Treatment of type 2 diabetes
No need for injections and many people can restore their normal blood glucose balance by: eating a balanced diet with carefully controlled amounts of carbohydrates, losing weight and doing regular exercise. If this doesn’t work there are drugs that help insulin work better on the body cells make more insulin in the pancreas and reduce the amount of glucose you absorb from your gut but if none of these work you probably need insulin injections.
The endocrine system gland:pituitary gland
Found in the brain -Controls growth in children - Stimulates the thyroid gland to make thyroxine (which controls rate of metabolism) - Stimulates ovaries to produce and release eggs in females - Stimulates testes to make sperm and testosterone in males
The endocrine system gland:adrenal
Located at the top of your kidneys secretes adrenaline which boosts the delivery of oxygen and glucose to your brain and muscles preparing for your body for flight or fight once danger over it stops, doesn’t involve negative feedback loop
Adrenaline causes
Your heart rate and breathing rate to increase
Stored glycogen in the liver to be converted to glucose for respiration
The pupils of your eyes to dilate to let in more light
Your mental awareness to increase
Blood to be diverted away from your digestive system to the bug muscles of the limbs
Endocrine system gland:ovaries(female)
Controls development of female secondary sexual characteristics and is involved in menstrual cycle also makes the female sex hormone oestrogen
Endocrine system gland:testes(male)
Controls the development of the male secondary sexual characteristics and is involved in the production of sperm
Endocrine system gland:pancreas
Controls the levels of glucose in the blood
Endocrine system gland:thyroid
In the neck uses iodine from diet to produce hormone throxide which controls the basal metabolic rate of the body(how quickly substances are broken down and built up, how much oxygen tissues use, how the brain of a growing child develops) plays an important role in growth and development buy in adults usually stays stable, this happens because of negative feedback vomteol involving pituitary gland and hormone it produces-thyroid stimulating hormone or TSH
Negative feedback system of throxine
If levels of thyroxine in the blood fall it’s detected by sensors in the brain so the amount of TSH released from the pituitary gland increases. TSH stimulates the production of thyroxine by the thyroid gland as the levels of thyroxine goes up it’s detected by the sensors and in turn the level of TSH released falls
If blood glucose levels rise from normal blood glucose level
Insulin is ‘secreted’ by the pancreas the effect of this is soluble glucose is converted into glycogen to be stored away in the liver it is also moved into the cells where it is used so blood glucose levels drop back to normal glucose level
If blood glucose levels drop from normal blood glucose level
Glucagon is ‘secreted’ by the pancreas the effect of this is the stored glycogen is converted back to glucose by making your liver break it down to the cells and bloodwhere it is used and amnio acids/fats are broken down so blood glucose levels rise back to normal blood glucose level
By using 2 hormones and the glycogen in your liver
Your pancreas keeps your blood glucose concentration fairly constant by using negative feedback control which involves switching between the 2 hormones
Autoimmune is
When the immune system attacks the pancreas
What is the negative feedback system
Works to maintain a steady state, if a factor in the internal environment increases changes take place to reduce it and restore the original level. And if a factor in the internal environment decreases changes take place to increase it and restore the original level. Whatever the initial change in negative feedback the response causes the opposite. Many hormones are involved in negative feedback systems like insulin and glucogen, most female sex hormones and thyroxine [LOOK AT DIAGRAM IN BOOK]
Day 1 of the menstrual cycle
Day 1 the lining breaks down and until day 7 oestrogen and progesterone as doesn’t move
Day 7 of menstrual cycle
The amount of progesterone released increases and the amount of oestrogen stays very similar until day 14 the lining is being built up at the moment but day 11 the amount of progesterone starts decreasing
Day 14 of the menstrual cycle
Egg is released and the lining is maintained as the oestrogen is back to normal levels by day 16 and the levels of progestrone start decreasing by day 22
Day 21 of the menstrual cycle
The egg has reached the uterus and the lining falls and it is ready for it to be fertilised
What is ovulation
When Every 28 days a mature egg is released
Puberty for boys
Penis testis and scrotum grow, body becomes more muscular and sperm is produced
Puberty for boys and girls
Sexual ‘drive’ develops, hair grows under arms and growth spurt
Puberty for girls
Vagina, oviducts and uterus develops, controlled by oestrogen and progesterone and breasts develop
Menstrual cycle is coordinated by the interaction what 4 different hormones
F-FSH or follicle stimulating hormone
O-oestrogen
L-LH or luteinising hormone
P-progesterone
FSH
started when it is secreted by the pituitary gland and makes eggs mature in their follicles in the ovaries and stimulates the ovaries to produce hormones including oestrogen.
Oestrogen
(the female sex hormone) is made and secreted by the ovaries in response to FSH and stimulates the lining of the uterus to grow again after menstruation in preparation for pregnancy also high levels of it inhibit the production of more FSH and stimulate the response of LH
LH
from the pituitary gland stimulates the release of a mature egg from the ovary once ovulation has taken place LH levels fall again
Progesterone
secreted by the empty egg follicle in the ovary after ovulation and is one of the hormones that help maintain a pregnancy if the egg is fertilised it also inhibits both FSH and LH and maintains the lining of the uterus in the second half of the cycle so it is ready to receive the a developing embryo if the egg is fertilised
Hormonal control –
contraceptive pill description
A pill containing oestrogen and progestogen(mixed) or just progesterone both taken orally use female hormones to prevent pregnancy. Mixed pill inhibit the production and release of FSH by the pituitary gland affecting the ovaries so no eggs mature which prevents pregnancy. Also the hormones also stop the uterus lining from developing and make mucus in the cervix thick to prevent sperm getting through
Hormonal control contraceptive pill advantages
Perfect use was over 99% often reduces bleeding and period pain, and may help with premenstrual symptoms can be used by women who smoke and are over 35
Hormonal control contraceptive pill disadvantages
Missing pills or late pills vomiting or severe diarrhoea can make it less effective and typical use is around 91% side effects include raised blood pressure, thrombosis and breast cancer the pills that contain only progesterone have fewer side effects than the mixed but if not taken regularly can lead to an unexpected release of an egg and a baby
Hormonal control contraceptive patch description
A small patch stuck to the skin and releases oestrogen and progesterone
Hormonal control contraceptive patch advantages
Perfect use is 99% can also make bleeds regular lighter and less painful
Hormonal control contraceptive implant disadvantages
Typical use is around 91% may be seen and can cause skin irritation
Chemical control spermicides description
Chemicals that kill or disable sperm
Chemical control spermicides advantages
Readily available
Chemical control spermicides disadavantages
Not very effective
Barrier methods condoms description
Thin latex material placed over the penis during sex to collect the semen and prevent the egg and sperm meeting
Barrier methods condoms advantages
No side effects and do not need medical advice and is the only method that offer some protection to STI’s
Barrier methods condoms disadvantages
No side effects but can get damaged and let the sperm through
Barrier methods diaphragm description
Thin rubber diaphragm placed over the cervix before sex to prevent the entry of sperm
Barrier methods diaphragm advantages
No side effects
Barrier methods diaphragm disadvantages
No side effects but must be fitted by a doctor initially and if it is not positioned correctly sperm may get past and reach the egg but barrier methods work better with spermicide
Intrauterine devices description
Small structures inserted into the uterus by a doctor lasting 3-5 yrs. some contain copper and prevent any early embryos implanting in the lining of the uterus. Others contain progesterone releasing it slowly to prevent the build up of the uterus lining and to thicken the mucus of the cervix
Intrauterine devices advantages
Very effective and can be removed at any time if you want to become pregnant
Intrauterine devices disadvantages
They have to be inserted by a doctor and may cause period problems or infections
Abstinence-rhythm method/natural family planning description
Abstinence-not having sex until they want to get pregnant.
Rhythm method- pulling out the penis so it does not release sperm into the vagina
Family planning-abstaining from sex on certain days when the egg is most fertile so they do not get pregnant when an egg is in the oviduct or around ovulation,ovulation indicators make it more effective
Abstinence-rhythm method/natural family planning advantages
Some religious groups don’t accept the use of artificial methods of contraception can be reliable and no side effects
Abstinence-rhythm method/natural family planning disadvantages
No side effects and can be very unreliable
Surgical methods description
Can be surgically sterilised for men the sperm ducts are cut and tied preventing sperm getting into the semen this is called a vasectomy and for women the oviducts are cut or tied to prevent the egg reaching the uterus and the sperm reaching the egg
Surgical methods advantages
Gives effective permanent contraception with no risk of human error
Surgical methods disadvantages
Women need a general anaesthetic for the surgery which comes with its own risks and you can’t have children at all any more
How many couples in the uk have problems having a family when they want one
1in 6 couples
There can be many explanations to problems having a family like
Lack of female hormones?
Damaged oviducts?
Lack of sperm in the semen?
Sperm with poor mobility
These problems with having a family when people want one and the explanations are often linked with
Obesity, eating disorders, alcohol/drug consumption, age
How can you treat fertilisation
Hormonal injection
IVF (In Vitro Fertilisation [in glass])
A lack of ovulation can mean
when women don’t make enough FSH to stimulate the maturation of the eggs in the eggs of their ovaries but artificial FSH can be used as a fertility drug that stimulates eggs in the ovary to mature and also triggers oestrogen production. An artificial form of LH can be used to trigger ovulation. This may mean they are able to get pregnant naturally.
IVF is a form of fertility treatment used if
the oviducts have been damaged or blocked by infection, if a donor egg has to be used, if there is no obvious cause for long term infertility or if a man produces very few sperm or the sperm do not mature properly individual sperm may be injected into the egg in the process.
IVF advantages
gives people the chance to have a baby of their own who wouldn’t be able to normally, mature eggs made by a woman using fertility drugs may be collected and stored or fertilised and stored until she wants to get pregnant later
IVF disadvantages
ethical issues of the mature fertilised eggs that may be abandoned or left when a person dies, expensive for NHS and society and individuals as many people end up doing repeated cycles, not always successful can use eggs or sperm from younger people but then it is not biologically your child, use of fertility drugs can have some health risks for the mother and the process is very emotionally and physically stressful, increases the chance of multiple pregnancy which causes problems and higher risks of stillbirths etc and costs the hospital more if they have any problems or severe disabilities.
Process of IVF
- Fertility drugs are used to make lots of eggs mature at the same time for collection.
- The eggs are collected and placed in a special solution in a petri dish.
- A sample of semen is collected
- The sperm and eggs are mixed together
- The eggs are checked to make sure they have been fertilised and the early embryos are developing properly
- When the fertilised eggs have formed tiny
balls of cells, one or two are placed in the Womb of the mother. Hopefully, at least one embryo will survive.
