Introduction to endocrine

Question 1

Function of the endocrine system

Answer 1

Maintenance of homeostasis within the body.

Co-ordinates body energy levels, growth and development, reproduction, responses to stress/injury etc.

Question 2

Endocrine glands

Answer 2

Secrete into the blood

Question 3

Exocrine glands

Answer 3

Have ducts

Question 4

Endocrine

Answer 4

Hormones are released into the blood and act upon a distal site

Question 5

Intracrine

Answer 5

Acts within the cell

Question 6

Autocrine

Answer 6

Acts upon the cell from which it is released

Question 7

Paracrine

Answer 7

Acts upon adjacent cells

Question 8

Juxtacrine

Answer 8

An intracellular communication. Requires the cells to be in physical contact

Question 9

Name the 4 classes of hormone

Answer 9

Steroid, derivatives of arachidonic acid, derivatives of phenylalanine, peptide

Question 10

Synthesis of peptide hormones

Answer 10

Can be stored.

Preprohormone –> prohormone –> active hormone

Question 11

Synthesis of arachidonic acid derivatives

Answer 11

Membrane PL –> arachidonic acid –> prostaglandins etc.

PLA, COX

Question 12

Synthesis of phenylalanine derivatives

Answer 12

PA –> tyrosine –> dopamine –> NA/A

Question 13

Synthesis of steroid hormones

Answer 13

Synthesised from cholesterol.
Synthesised as required
4 classes: corticoids, progestin, androgens and oestrogens

Question 14

Mechanism of peptide/phenylalanine/arachidonic acid hormone signalling

Answer 14

Via cell surface receptors. Signals through second messenger systems which change cellular activity e.g. enzymatic
**as water soluble

Question 15

Mechanism of steroid hormone signalling

Answer 15

Lipid soluble and so cross the membrane, bind to cytoplasmic/nuclear receptors. Cause changes within gene transcription of receptive genes