Endocrine communication

Question 1

endocrine system

Answer 1

a communication system using hormones as signalling molecules.

Question 2

hormones

Answer 2

molecules that are released by endocrine glands directly into the blood. They act as messengers, carrying a signal from the endocrine gland to a specific target organ or tissue.

Question 3

target cells (for non steroid hormones)

Answer 3

cells that possess a specific receptor on their plasma membrane. The shape of the receptor is complementary to the shape of the hormone molecule. Many similar cells together form a target tissue.

Question 4

What circulatory system does the endocrine system use to transport its signals?

Answer 4

blood.

Question 5

What are the two types of hormones?

Answer 5

• protein and peptide hormones, imitating amino acids.
  (e.g adrenaline, insulin and glucagon)
• steroid hormones
  (e.g. oestrogen and testosterone)

Question 6

How do protein hormones work?

Answer 6

they are not soluble in the phospholipid membrane and do not enter the cell. Protein hormones need to bind to the cell surface membrane and release a second messenger inside the cell.

Question 7

How do steroid hormones work?

Answer 7

can pass through the membrane and enter the cell and the nucleus, to have direct effect on the DNA in the nucleus.

Question 8

How are hormones released directly into the blood?

Answer 8

The endocrine glands.

Question 9

What are the endocrine glands

Answer 9

ductless glands
consist of groups of cells that manufacture and release the hormone directly into the blood in capillaries running through the gland.

Question 10

The endocrine organs in the human body?

Answer 10

• pituitary gland
• thyroid gland
• thymus
• adrenal glands
• pancreas
• ovaries (females)
• testes (males)

Question 11

What are the cells receiving the endocrine signal called?

Answer 11

target cells

Question 12

peptide hormones

Answer 12

known as first messengers
signalling molecules outside the cell that bind to the cell surface membrane and initiate an effect inside the cell.
cause the release of another signalling molecule in the cell. known as second messenger stimulates a change in activity of the cell.

Question 13

first messengers

Answer 13

peptide hormones

Question 14

second messengers

Answer 14

signalling molecules

Question 15

G protein

Answer 15

how many peptide hormones act
is activated when hormone binds to the receptor.
It activates an effector molecule.
most molecules enzyme= adenyl cyclase

Question 16

What does adenyl cyclase do/

Answer 16

converts ATP to cyclic AMP.