B3.2 The Endocrine System Flashcards
What are hormones?
Hormones are chemical messengers which travel in the blood and control body processes that need constant adjustment
What is homeostasis?
The maintenance of a constant internal environment
What are endocrine glands?
Glands that produce and secrete a hormone
What is the endocrine system
All endocrine glands and the hormones they produce
What are target organs?
Organs a hormone has an effect on
Differences between nervous impulses and hormones
Nerves travel to specific parts of the body, however hormones travel all around the body but only target organs respond. Nerves communicate very fast but hormones are slower. Nerves are short acting but hormones are long actingm
How do hormones work on target cells
Hormones diffuse out of blood to bind specific receptors on target cells. The receptors then stimulate the hormonal response.
Thyroid gland hormones
Thyroid gland secretes thyroid hormones which control the body’s metabolic rate
What is thyroxine
Thyroxine is a hormone produced in the thyroid gland, and it plays a vital role in regulating the body’s basal metabolic rate/
Function of thyroid gland
To take iodine and convert it into thyroxine by combining it with the amino acid tyrosine
What is negative feedback
Negative feedback is a system that detects a change in a condition. The system then acts to return conditions back to the desired level
Adrenal glands located
Adrenal glands are located on top of both kidneys
Adrenal gland hormones
At times of stress they secrete the hormone adrenaline, which prepares the body for intensive action, also known as ‘fight or flight’ response
Effects of adrenaline
Adrenaline increases rate of ATP production, increases rate of breathing, increases heart rate, and diverts blood to muscles.
What is the menstrual cycle
the menstrual cycle is the reproductive cycle of female humans which is controlled by reproductive hormones. It prepares the woman’s body for pregnancy.