B11 - Hormonal Coordination Flashcards
What’s the endocrine system?
A system of glands which secrets hormones into the bloodstream.
What’s a hormone?
Chemicals produced by glands and transported in the bloodstream which only affect their target organs and cause them to produce a response.
What’s the pituitary gland also known as?
The master gland
Where is glucose stored and what is it stored as?
Glycogen in your muscles and liver
What happens when glucose levels get too low?
The pancreas releases glycagon which causes the breakdown of glycogen into glucose.
What is glycagon?
Causes blood glucose levels to rise
What does insulin do?
Causes blood glucose levels to fall
What happens when blood glucose levels get too high?
The pancreas releases insulin which causes more glucose to move to cell for respiration and glucose that moved to muscle and liver cells is stored as glycogen.
What is the pituitary gland?
Tells the hormones to control all apart from pancreas as it has small amount of brain tissue.
What happens to glucose levels when a person eats?
Increases
What is the endocrine gland?
An organe that secrètes hormones into the bloodstream.
Why is the pituitary gland called the master gland?
Because it controls the other hormones apart from pancreas.
What’s the definition of diabetes?
A group of disorders where people are unable to control their blood glucose levels.
What’s the definition of type 1 diabetes?
A disorder in which the pancreas fails to produce sufficient insulin causing high blood glucose levels.
What’s the definition of type 2 diabetes?
A disorder in which the body cells no longer respond to insulin which is still produced by the pancreas. This causes both high insulin levels and high blood glucose levels.
What’s the cause of type 1 diabetes?
High blood glucose levels
What’s the cause of type 2 diabetes?
High insulin levels and high glucose levels.
What’s the definition of negative feedback system?
A system which reverses any changes to it keeping factors within acceptable levels.
What’s thyroxine?
A hormone secreted by the thyroid gland that is transported in the blood.
What does thyroxine do?
Régulâtes the basal metabolic rate in cells which controls growth and development.
What happens when thyroxine levels rise?
Less thyroxine is secreted by thyroid and pituary gland secrets less TSH
What happens when thyroxine levels fall?
More thyroxine secreted by gland and pituitary gland secrets more TSH.
What does TSH stand for?
Thyroid stimulating hormone
When is adrenaline produced?
Only when necessary and then it’s production stops and levels drop back to zero and breaks down
What is adrenaline?
A hormone produced by adrenal glands during times of stress or fear.
How is adrenaline transported?
In the blood to many tissues and organs
What does adrenaline increase?
Heart rate
Oxygen delivery to brain and muscles
Glucose delivery to brain and muscles
What’s the definition of puberty?
The development of secondary reproductive characteristics, leading to fertility.
What physical changes trigger follicle stimulating hormone (FSH)v
Egg natures in their follicles in the ovaries
What physical changes trigger oestrogen?
Stimulates the lining of uterus to grow again after menstruation in preparation for pregnancy.
What physical changes trigger luteinising hormone (LH)?
Stimulates the release of a mature egg from the ovary.
What physical changes trigger progesterone?
Helps maintain a pregnancy if egg is fertilised.
Maintains the lining of the uterus in second half of cycle.
Where is FSH produced?
Pituitary gland
Where is oestrogen produced?
Follicle/ovary
Where is LH produced?
Pituitary gland
Where is progesterone produced?
Follicle/ovary
Results of FSH?
Stimulates the ovaries to produce hormones including oestrogen.
Results of oestrogen?
High levels inhibit the production of more FSH and stimulate the release of LH.
Results of LH?
LH levels fall again once ovulation takes place.
Results of progesterone?
Inhibits both FSH and LH.
Contraception definition
Preventing sperm cells and egg cells from fusing to stop unwanted pregnancy
What are two hormone based contraception?
Oral contraception (The Pill)
Implants, patches or injections
What hormones are in oral contraception?
Progesterone (and sometimes oestrogen) that inhibit FSH which stops from maturing
What hormones are in implants, patches or injections?
Progesterone that inhibits FSH
What are the 5 non-hormonal contraceptions?
Barriers (condoms, diaphragms)
Spermicide - kills sperm
Intrauterine device
Abstinence shortly after ovulation
Surgical methods (tubectomy (F) vasectomy (M))
What causes infertility in men?
Low motility of sperm
No/little sperm production
Age
What causes infertility in women?
Insufficient FSH
Weight
Age
What is treatment 1 for infertility?
Fertility drugs before natural conception.
FSH and LH injections stimulate ovulation. The woman then gets pregnant in the normal way.
What are the 4 stages of treatment 2 for infertility?
- FSH and LH injections stimulate egg maturation.
- Eggs collected from the mother, then mixed with sperm in a petri dish.
- Fertilised eggs develop into embryos.
- When several embryos become balls of cells, they are inserted back into uterus.
What’s an advantage of treatment 2?
Allows infertile people to have babies.
What’s a disadvantage to treatment 2?
Emotionally and physically stressful
Low success rate
High risk of multiple births, riskier birth
What is treatment 2?
IVF
How are hormones versatile?
Can activate more than one target organ.
Can cause different responses in different tissues.
Can produce different responses at different concentrations.
What’s auxin?
A growth hormone in plants which causes tropisms.
What is topisms?
Directional growth in responses to a stimulus.
What is photo tropism?
Growth in response to light.
What is gravitropism?
Growth in response to fractional field (roots growing down to the ground cus of gravity)
Where is auxin produced?
The tip of plant
Where does auxin move in shoots?
To the shaded side of the plant
What does auxin do in shoots?
Helps cell grow quicker
What does uneven auxin distribution cause?
Uneven elongation which causes bending
What does auxin act as in roots?
A growth inhibiter
Where does auxin move in roots and what does it cause?
Moves to lower side and makes the root bend downwards
What is agriculture definition?
Growth of plants for food
What is horticulture?
Growth of plants for aesthetic purposes
What are the uses of auxin?
Rooting powders for cutting
Weed killer - causes excessive growth
What are uses of gibberellins?
To speed up germination (seed sprouting)
To make plants flower earlier
To increase fruit size
What is a use of ethene gas?
To speed up ripening during storage
