B11 - Hormonal Coordination 2️⃣✅ Flashcards
Label the diagram of the endocrine system.
What is the gland that is refered to as the ‘master gland’?
The pituitary gland
What does the pituitary gland secrete?
Secretes numerous hormones with many acting on other endocrine glands
What does the pancreas secrete?
Secretes the hormone insulin
What does the thyroid gland secrete?
Secretes thyroxine
What do the ovaries secrete?
Secretes oestrogen and progesterone
What do the testes secrete?
Secrete testosterone
What does the adrinal gland secrete?
Secretes a wide range of hormone involved in homeostatis and especially adrenaline
What does adrenaline do?
Prepares the body for ‘flight or fight’ and it:
* increases heart rate
* boosts delivery of oxygen and glucose to the brain and muscles
What does insulin do?
Lowers the bodys blood sugar levels
What does thyroxine do?
Its important in growth and metabolic rate
Complete this fill in the gaps on the nervous and endocrine system
The messages in the nervous system travel ____ but in the hormone system they travel ____. The hormone system is made up of ____ but the nervous system is made up of ____.
Messages are carried by ____ in the nervous system but carried by ____ in the endocrine system
The effect of the messages carried by the ____ usually only last a short time but those carried by the ____ usually last longer.
The messages in the nervous system travel quickly but in the hormone system they travel slowly. The hormone system is made up of glands but the nervous system is made up of nerves.
Messages are carried by nerve cells in the nervous system but carried by blood in the endocrine system
The effect of the messages carried by the nervous system usually only last a short time but those carried by the endocrine system usually last longer.
What gland produces a hormone which reduces the level of blood sugar?
Pancreas (insulin)
What gland is involved in the production of sex cells and the release of the female sex hormones?
Ovaries (oestrogen & progesterone)
What gland requires iodine to produce its hormone?
Thyroid gland (requires iodine to produce thyroxine)
What gland produces its hormone in conditions of stress or excitement?
adrinal gland (adrenaline)
Why do we need to make sure we have optimum blood glucose levels?
Because glucose is the energy source for all respiraton - which is used for cell division, protein syntheis and therefore the production of enzymes etc…
What 2 hormones are required to maintian blood glucose levels?
Insulin & Glucagon
What does insulin do?
InsuLin Lowers levels
Insulin lowers blood glucose levels when they are too high
What does Glucagon do?
When glucose is GONe you need glucaGON
Glucagon raises your blood glucose levels if they are too low
What happens if our blood glucose levels are too low?
We wont have any energy for respiration and therefore many other things insdie the body e.g. cell division
What happens if our blood glucose levels are too high?
If its too high then our cells start to dehydrate (affecting osmosis) and are damaged
What does our body do if blood glucose is too low?
Pancreas releases glucagon which causes glygogen to be converted into glucose therefore increasing levels
What is type 1 diabetes?
- The pancreas fails to supply sufficient insulin
- therfore patients suffer from high glucose levels
- treated with insulin injections
What is type 2 diabetes?
- Body cells no longer respond to insulin produced by pancreas
- Obesity is a common risk factor involved with Type 2
- treated with a carbohydrate based diet and exercise
How does negative feedback play a part in controlling blood glucose levels?
- Glucagon and insulin both are released accordingly to the bodys concentration of blood glucose
- negative feedback works by glucose/ insulin feeding back to the pancreas when they have both done their respective jobs to make sure the pancreas stops producing them so that the levels stay constant within the narrow limits/optiumum conditions e.g. over/undershoot.
What is negative feedback?
An action taken by the body to retain something within its optiumum conditions/ within narrow limits
What is a target organ?
An organ with complementary receptors for specific hormones on its surface
Label this diagram of the male reproductive system
Label this diagram of the female reproductive system
What 2 hormones are released by the ovaries?
Oestrogen & progesterone
What 2 hormoes are released by the pituitary gland?
(in relation to the female reproductive system)
Folicle stimulating hormone - FSH
Lutenizing hormone - LH
In what order are the 4 hormones involved in the menstrual cycle released?
- FSH
- Oestrogen
- LH
- Progesterone
What hormone is released for the shortest time in the menstrual cycle?
LH
What does FSH do?
Causes the maturation of an egg
What does Oestrogen do?
Stimulate the regrowth of the uterus lining
What does LH do?
Stimulate the release of an egg
What does progesterone do?
Keeps lining from shedding - keeps it developed due to implantation of egg
What is another name for progesterone?
The pregnancy hormone as it keeps lining if you are pregnant
Also progesterone - gestation - duration of a pregnancy - easy way to remember
What does IVF stand for?
In
Vitro
Fertilisation
List some barrier methods for contraception
- femidom (+spermicide)
- condom
- diaphragm
What is the negative feedback relationship in the menstrual cycle?
High oestrogen concentration switches of FSH production (so that no mor eegs mature)
What is a easy way to remeber the order of secretion of hormones in the menstrual cycle?
F - SH
O - estrogen
L - H
P - rogesterone
What does the progesterone only pill do?
- grows the uterus lining so thick that sperm cant get through as easily
- the presence of progesterone inhibits FSH & LH production therefore no ovulation
What doe the mixed pill do and contain?
- It contains oestrogen and progesterone
- the presence of oestrogen inhibits FSH production therfore no egg maturation
- the presence of progesterone inhibits FSH & LH production therefore no ovulation
How do plants respond to their environment in terms of growth?
Plants grow towards or away from the stimulus in their environment
What is a growth response called?
A tropic response
What are the 3 main stimulus that affects plants?
- light
- water
- gravity
What is it called when a plant responds to light?
phototropism
What is it called when a plant responds to water?
hydrotropism
What is it called when a plant responds to gravity?
geotropism/ gravitropism
What is a hormone?
Hormones are chemical messengers released by glands into the blood and carried to a target organ or organs
What is a gland?
An organ or tissue that synthesises and secretes a chemical messenger such as a hormone into the blood plasma
What is contraception?
Contraception is the term used to describe interventions that can stop fertilisation adn therefore pregnancy from occurring
What does the contraceptive implant do?
- Like the mixed pill - contains oestrogen and progesterone
- instead of ingestion the hormones are absorbed into the bloodstream
What is spermicide?
- A chemical method of contraception
- only 10% affective - usually coupled along side a femidom for maximum efficiency
What are intrauterine devices?
Small structures e.g. coil that are inserted into the uterus by a doctor some contain progesterone.
How does IVF work?
(6 listed steps in order)
- Woman is implanted with artificial FSH to stimulate release of egg
- Mature eggs are harvested from ovaries using fine needle
- Mature eggs are mixed with sperm in test tube & incubated for 24 hours
- If fertilisation has occured 2 nuclei will be seen - 1 from egg, 1 from sperm
- The fertilised egg undergoes mitosis and divides to form a tiny ball of cells called an embryo
- The embryo is placed into the uterus and should implant to develop into a baby
What are some of the cons to IVF?
- very emotionally and physically stressful
- sucsess rates are not high
- it can lead to multiple births which are a risk to babies and mother
What is so important about thyroxine and what makes it different to adrenaline?
- Thyroxine controls our metabolic rate
- It needs to be kept within narrow limits
- Therefore its controlled by negative feedback
- Adrenaline is not controlled by negative feedback - its controlled by a ‘stress response’ and is released in times of fear and stress by the adrinal gland - you only release adrenaline when you need it therefore it is not distributed by negative feedback
What do auxins do?
controls the growth/ stimulates of plants by promoting cell division and causing elongation in plant cells at the root tips and shoot tips
What does the plant hormone Ethylene do?
Ethylene is a plant hormone that regulates growth & ripening / ripening of fruits, opening of flowers & shedding of leaves e.g. can reduce/ increase ripening
What does the plant hormone Gibberellin do?
Gibberellin important for initiating seed germination.
How does insulin lower blood glucose levels?
Upon an increase in bood glucose levels the pancreas releases insulin. The insulin released into the blood stream b inds to receptors on liver/ muscle cells. This causes the glucose molocules that are taken up by the liver & muscle cells to form glycogen; removed from blood and therefore blood glucose levels decrease back down to normal
What is glycogen?
A large molocule that stores lots of smaller glucose molocules
What happens to auxins after they are produced?
After being produced in root tips/ shoot tips they diffuse backwards down the root/ shoot they are in
What do auxins do in shoots?
They stimulate growth
What do auxins do in roots?
They inhibit growth
For phototropism where will auxins always accumulate?
On the shade side, not the sunny side so when auxins promote growth on the one side away from the sun the shoot ends up curving towards the light
For gravitropism/ geotropism where will auxins always accumulate?
On the bottom side, not the top side so when auxins inhibit growth the top side grows more and ends up pointing the root down towards the ground
What is germination?
The growth/ development of a plant from a seed or spore after a period of dormancy.
