endocrine system

Question 1

What is the endocrine system?

Answer 1

A network of endocrine glands that functions as a chemical messenger system

Question 2

What are hormones?

Answer 2

Chemical messengers produced by endocrine glands. They can be proteins/peptides/amino acid derivatives (hydrophilic) or steroids (hydrophobic).
* hormones regulate many bodily functions
* metabolism
* growth
* sexual function
* concertation of glucose and eletrolytes in the blood.

Question 2

What are protein hormones like, and where are their receptors located

Answer 2

Protein hormones are hydrophilic and their receptors are on the plasma membrane of target cells

Question 2

What are steroid hormones like, and where are their receptors located?

Answer 2

Steroid hormones are hydrophobic and their receptors are in the cytosol/nucleus of target cells

Question 3

How do endocrine glands release hormones?

Answer 3

They release hormones directly into the bloodstream, without using ducts

Question 4

What are the two major lobes of the pituitary gland? and it’s function

Answer 4

The anterior pituitary and the posterior pituitary
* forms a link between the brain and other endocrine glands
* it is the target of hormones produced by the hypothalamus

Question 5

What type of tissue makes up the anterior pituitary? and it’s function

Answer 5

Glandular epithelial cells with interspersed capillaries
* acted on by hormones from the hypothalamus
* e.g. TAH from the hypothalamus causes TRH to be released by the anterior pituitary gland.

Question 6

What type of tissue makes up the posterior pituitary? and it’s function

Answer 6

Nervous tissue consisting of nerve fibers and nerve endings from the hypothalamus
* doesn’t produce hormones
* recieves hormones from the hypothalamus via verve fibres and stores hormones e.g. ADH (targets kidneys) and oxytocin (targets the uterus)
* hormones sre stored and later released

Question 7

What are the two main regions of the adrenal glands?

Answer 7

The outer cortex and the inner medulla

Question 8

What type of tissue is the adrenal cortex and what does it produce?

Answer 8

Glandular tissue that produces corticoid hormones (steroids) like aldosterone and cortisol

Question 9

What type of cells make up the adrenal medulla and what do they produce?

Answer 9

Chromaffin cells (modified nerve cells) that produce adrenaline and noradrenaline
* produces adrenalin and noradrenaline - fight and flight response leading to increased heart rate and glucose release

Question 10

targets tissues and receptors

Answer 10

receptor size;
* location on a cell where hormone binds (lock)
target tissue;
* group a cells that respond to specific hormones
specificity;
* specific hormones bind to specific receptor sites

Question 11

hypothalamus

Answer 11

• acts as a link between the nervous and endocrine system
• produces hormones that act on the pituitary gland.

Question 12

which system is faster

Answer 12

the nervous system is faster than the endocrine as the nerve cells are larger and making them better at spreading messages and signals throughout the body.

Question 13

thyroid gland

Answer 13

• 2 lobes joined by connective tissue in the lower neck.
• secretes T4 and T3 (collectively known as thyroid hormone TH)
• TH regulate metabolism, growth and development

Question 14

parathyroid glands

Answer 14

• 4 parothyroid glands - 2 behind each lobe of the thyroid
• produces parathyroid hormone (PH) which is involved in blood calcium regulation by acting on bones and kidneys.