C14 - Hormonal Communication

Question 1

What is the role of an endocrine gland?

Answer 1

Secrete hormones into blood stream

Question 2

Describe the role of the pituitary gland

Answer 2

Secrete

• growth hormone for bones and muscles
• ADH - increases reabsorption of water in kidney
• Gonadotrophins - development of ovaries and testes

Question 3

Describe the role of the pineal gland

Answer 3

secrete

- melatonin - reproductive development and daily cycles

Question 4

Describe the role of the thyroid gland

Answer 4

secrete:

- thyroxine - controls rate of metabolism, rate at which glucose is used in respiration, promotes growth

Question 5

Describe the role of the thymus

Answer 5

secretes:

-thymosin - promotes production and maturation of WBCs

Question 6

Describe the role of the adrenal gland

Answer 6

secretes:

- adrenalin - increases heart rate, breathing and blood glucose levels

Question 7

Describe the role of the glands in the pancreas

Answer 7

secrete:

• insulin - converts glucose to glycogen
• glucagon - converts glycogen to gluose

Question 8

Describe the role of the glands in the testis

Answer 8

secrete:

-testosterone - sperm production and secondary sexual characteristics

Question 9

Describe the role of the glands in the ovary

Answer 9

Secrete:

• oestrogen - ovulation and secondary sexual characteristics
• progesterone - prepares uterus lining for receiving an embryo

Question 10

Compare Nervous and hormonal communication

Answer 10

(DS SPITS)
Duration
---N (short) H (slow and long)
Speed
----N (fast) H (slow)
Structures
----N (neurones) H (glands/secretory cells)
Pathway
----N (neurones) H (bloodstream)
Information
----N(electrical impulses) h (hormones/chemicals)
Target
----N(localised) H(whole organ/tissue)
Similarities
----cell signalling

Question 11

How do steroid hormones work

Answer 11

hormones that can work their way through the phospholipid bilayer, binding to proteins, act as TRANSCRIPTION factor to effect change

Question 12

What are the chemical properties of steriod hormones

Answer 12

Derived from cholestrol
hydrophobic
insoluble in water

Question 13

How do non-steroid hormones work

Answer 13

bind to receptor on plasma membrane

affect cellular processed through second messengers

Question 14

Give an example of a second messenger

Answer 14

CAMP

Question 15

What are the chemical properties of non-steriod hormones

Answer 15

proteins

water soluble

Question 16

What hormones are produced in the adrenal medulla?

Answer 16

Adrenelin

Question 17

What hormones are produced in the adrenal cortex?

Answer 17

• cortisol
• aldosterone
• androgen

Question 18

What is cortisol?

Answer 18

Steroid hormone produced in adrenal cortex
increases blood sugar levels
acts on GLUCOCORTICOID receptor in nulceus

Question 19

What is aldosterone?

Answer 19

Steriod hormone produced in adrenal cortex
controls blood pressure and sodium conversion in kidney
MINERALCORTICOID receptor in nucleus

Question 20

What is androgen?

Answer 20

Steriod hormone produced in adrenal cortex

precursor to testosterone and oestrogen

Question 21

What is adrenaline?

Answer 21

non-steriod hormone produced in adrenal medulla

controls fight/flight response and glycogenolysis (which will increase blood sugar levels)

Question 22

What part of the nervous system controls the production of noradrenaline?

Answer 22

Autonomic sympathetic

Question 23

What part of the nervous system controls the production of acetylchloine?

Answer 23

Autonomic parasympathetic

Question 24

Describe how adrenaline acts on a cell to increase the availability of glucose

Answer 24

Adrenalin binds to receptor site on cell surface membrane
Enzyme (adenylyl cyclase) inside membrane is activated
ATP converted to CAMP (second messenger)
CAMP activates a cascade of enzymes that eventually convert glycogen to glucose

Question 25

Describe the process in the body (starting at the amygdala) that result in the release in adrenalin in bloodstream

Answer 25

amygdala sends signal to hypothalamus Sympathetic NS activated noradrenaline released causes adrenal medulla to release adrenaline

Question 26

Describe the process in the body (starting at the amygdala) that result in the release in cortisol etc. in bloodstream

Answer 26

amygdala sends signal to hypothalamus pituatory gland releases ACTH (precursor to cortisol) Arrive at adrenal cortex Converted and released

Question 27

In the pancreas, what is resposible for digestive enzymes?

Answer 27

Acini cells

Question 28

In the pancreas, what is resposible for blood sugar hormones?

Answer 28

Islets of langerhans alpha - glucagon beta - insulin

Question 29

What. is the name of the process converting glycogen to glucose

Answer 29

glycogenolysis

Question 30

What. is the name of the process converting glucose to glycogen

Answer 30

Glycogenesis

Question 31

What. is the name of the process producing glucose from non-carbohydrate sources

Answer 31

Gluconeogenesis

Question 32

Describe how an increase in glucose leads to insulin being released

Answer 32

Resting potential in cell (-70mV) BS levels rise - Glucose enters cell via facilitated diffusion Glucose is matabolised and ATP is produced ATP binds to K channels, causing them to close K+ can not diffuse out, pd rises (-30mV) Voltage gated Ca2+ channels rise Ca2+ enter cell, causing excretory vesicles to release insulin via. exocytosis

Question 33

What is type 1 diabetes?

Answer 33

loss of beta cells failure to produce enough insulin genetic predispoition/autoimmune

Question 34

What is type 2 diabetes?

Answer 34

- failure to respond to insulin | - caused - excessive body weight/ insufficient excercise

Question 35

What are the symptoms of diabetes?

Answer 35

Weight loss Hunger Tiredness Glucose in urine

Question 36

What are the treatments for diabetes?

Answer 36

``` Type 1 - regular BS monitoring insulin injection Type 2 - drugs - exercise -regulation of food ``` Pancreatic transplants

Question 37

What controls our heart rate

Answer 37

Autonomic NS | Medulla oblongata

Question 38

What do the 2 centres in the Medulla oblongata that control our heart rate do?

Answer 38

``` 1- increase bpm sympathetic ns accelerator nerve 2- decrease bpm - parasymapthtic ns vagus nerve ```

Question 39

What are 2 receptors that help control our bpm and where are they found

Answer 39

``` Barorecetors blood pressure aorta, vena cava, carotid arteries Chemoreceptors - conc of chemicals eg. CO2 aorta, cartoid artery, medulla ```

Question 40

How do receptors change our bpm

Answer 40

Impulses sent to SAN, thus changing bpm

Question 41

How do Adrenaline and noradrenaline change our heart rate

Answer 41

Change frequency of SAN impulses directly