Endocrine System Flashcards
What is sensitivity?
The ability to detect change and to respond is called sensitivity.
What is response?
Response is a form of defence that allows organisms to survive.
What is the endocrine system?
The endocrine system is a group of specialised tissues (glands) that produce chemicals called hormones, many of which are proteins
Hormones
Hormones are chemical “messengers”, produced in specialised glands, and transported in the blood to a particular area (the target organ), where they have their effect.
Where are hormones produced?
in specialised glands
What happens to hormones after they are produced?
They are transported in the blood to a particular area (the target organ), where they have their effect.
Where do hormones have their effect?
The target organ
What are the endocrine glands often called?
ductless glands
What do exocrine glands have that endocrine do not and what are they used for? Give an example
Exocrine glands have ducts to carry their secretions, e.g. salivary glands.
What do the endocrine glands work with and what do they do?
The endocrine glands interact with the nervous system to provide the communication, co-ordination and control within the body.
What is the action of hormones like and what do they control?
The action of hormones is slower and more general than nerve action and they control mainly long-term changes such as growth, metabolism and sexual maturity
What happens when hormones pass through the liver
On passing through the liver, the hormones are broken down and excreted by the kidneys.
What does the nervous system rely on and what is it involved in?
The nervous system relies on electrical signals, carried by specialised cells, and is involved in fast responses
What does the brain region do?
keeps a check on internal organs and activities, such as the level of carbon dioxide or water in the blood.
What is most hormone activity controlled by?
Most hormone activity is controlled directly or indirectly by the hypothalamus and pituitary gland.
What is the pituitary gland often called and what does it do?
They pituitary is often called the “master gland”, as many of its hormones trigger other glands to release theirs.
What does the pituitary gland produce?
It produces ADH to stimulate water reabsorption in the kidneys, TSH which stimulates the thyroid gland to release thyroxine and FSH which controls the fuctions of the reproductive organs.
Where is the the thyroid, what does it produce and what does this stimulate?
They thyroid gland, in the neck, produces thyroxine, which stimulates metabolism
what does the parathyroid produce and what does this increase?
The parathyroid produces parathyroid hormone, which increases blood calcium levels
What type of gland is the pancreas?
The pancreas is both an endocrine and exocrine gland
What does the Islete of Langerhans produce and what does the rest produce?
The Islete of Langerhans produces insulin, while the rest of the pancreas produces enzymes for digestion
What does insulin do?
stimulatese cells to absorb glucose from the blood, and store it as glycogen
What does the adrenal gland do?
produces adrenaline which helps the body cope with emergencies - the “flight of fight” hormone
What does the ovary do?
Produces oestrogen and progesterone to prepare the female for pregnancy
What do the testes do?
Produce testosterone which triggers sperm production and growth in the male
What can endocrine glands sometimes do?
malfunction
What can low levels of thyroxine do?
reduce the rate of metabolsim.
What can solve the problem of low levels of thyroxine?
Taking the hormone in tablet form once a day can solve the problem - hormone supplement
What can excess thyroxine do?
Excess thyroxine can greatly increase metabolic rate
What is the treatment for excess thyroxine?
Treatment is often by removal of part of the gland
What is it called when the pancreas cannot produce insulin?
In some people, the pancreas cannot produce insulin, which results in diabetes mellitus
What happens to glucose in diabetes mellitus?
Glucose cannot get into cells, which disrupts metabolism.
What is required if you have diabetes mellitus?
Regular daily injections of insulin are required - hormone supplement
What are taken to prevent pregnancy?
In oral contraceptives , oestrogen and progesterone are taken to prevent pregnancy - hormone supplement
