Principles of endocrine control

Question 1

GLANDS

Answer 1

epithelial tissue derivatives specialised for secreting

Question 2

SECRETION

Answer 2

biochemical release from particular type of cell upon stimulation

Question 3

ENDOCRINE

Answer 3

secretions that enter the blood stream
ductless gland
End-internal gland-secretion

Question 4

AUTOCRINE

Answer 4

cell produced substance that has an effect on the cell by which it is secreted

Question 5

PARACRINE

Answer 5

hormone which has an effect only in the vicinity of the gland secreting it

Question 6

NEUROENDOCRINE

Answer 6

mechanism by which the hypothalamus maintains homeostasis composed of neurones

Question 7

HORMONE

Answer 7

chemical messenger that is secreted into the blood by endocrine glands in response to an appropriate signal-exerts effects on target cells which have receptors for the hormone

Question 8

2 types of hormones

Answer 8

hydrophilic and lipoohilic

Question 9

Hydrophilic hormones

…eg

Answer 9

• Peptides and catecholamines

- Adrenaline and noradrenaline

Question 10

Lipophilic hormones

…eg

Answer 10

• steroids

- eg thyroid hormone

Question 11

Peptide hormones

4 main points

Answer 11

• produced by normal protein synthesis machinery
• travel in blood solution
• cannot enter cells directly through the lipid bilayer
• bind to cell surface receptors
• trigger an event inside the cell (second messenger system)
• fast acting

Question 12

Example of a peptide hormone

Answer 12

Insulin

Question 13

Steroid hormones-main points

Answer 13

• produced by modification of cholesterol molecules
• travel in the blood count to plasma proteins
• enter cells easily
• intracelluar receptors
• Act on DNA to alter cell function-
• slow acting (transcription delay)

Question 14

what does the endocrine system regulate

Answer 14

• metabolism, water and electrolyte balance
• stress response
• growth and development
• reproduction
• RBC production
• coordination of circulation and digestion

Question 15

Pituitary gland

Answer 15

• Anterior and pituitary

- connects to the hypothalamus via the pituitary gland

Question 16

Hypothalamus

Answer 16

control of pituitary hormone release

interface between inside and outside of the body

Question 17

Hormones released from hypothalamus

Answer 17

• CRH (corticotrophin releasing hormone)
• GnRH gonadotrophin releasing hormone
• Dopamine (protecting inhibiting factor)

Question 18

What does the anterior pituitary control?

Answer 18

Activity of other endocrine glands that will then control:

• ovulation and pregnancy
• sperm production
• growth

Question 19

What hormones are released from the anterior pituitary?

Answer 19

• thyrotrophin (thyroid stimulating hormone)
• LH
• FSH
• Growth hormone
• prolactin

Question 20

what links the anterior pituitary with the hypothalamus?

Answer 20

blood vessels

Question 21

what is the posterior pituitary involved with regulating?

Answer 21

• overall water balance
• uterine contraction
• ejection of milk

Question 22

What hormones are released from the posterior pituitary?

Answer 22

ADH (antidiuretic hormone)

oxytocin

Question 23

what links the posterior pituitary to the hypothalamus?

Answer 23

Neurones

Question 24

What are the testis?

Answer 24

male external genitalia

they masculine the reproductive tract

Question 25

what do the testis do?

Answer 25

- promote growth and maturation of reproductive system at puberty - develop sex drive - secondary sexual characteristics

Question 26

what are secondary sexual characteristics?

Answer 26

pubic hair, adams apple...

Question 27

what is spermatogenesis?

Answer 27

development of spermatozoa by meiosis and mitosis

Question 28

which hormone is produced in the testes?

Answer 28

testosterone

Question 29

where does testosterone act in the cell?

Answer 29

on the nucleus

Question 30

Look at the diagram of spermatogenis

Answer 30

learn

Question 31

Which hormone causes the release of LH and FSH?

Answer 31

GnRH

Question 32

Does GnRH cause positive or negative feedback on FSH + LH?

Answer 32

Positive feedback

Question 33

During spermatogenesis what does FSH do?

Answer 33

Stimulates the sertoli cells to cause spermatogenesis OR release inhibin which negative feedback's and stops/slows the release of LH and FSH

Question 34

What does LH do during spermatogenesis?

Answer 34

Stimulates the leydig cells to produce testosterone | -this the stimulates spermatogenesis

Question 35

Draw out the diagram of spermatogenesis

Answer 35

...

Question 36

What do the ovaries do?

Answer 36

- stimulate the maturation and maintenance of the female reproductive system - ova maturation and release - prepare the uterus for development of n embryo and foetus

Question 37

what are the female secondary sexual characteristics?

Answer 37

pubic hair, breast enlargement

Question 38

what hormones are released by the ovaries?

Answer 38

Oestrogen and progesterone ( which are both steroids)

Question 39

what is the sequence of follicle formation?

Answer 39

``` primordial follicle (13-50yo) primary follicle (prenatal) secondary follicle (astral follicle 15-20days) graafian follicle (mature follicle) ovulation ```

Question 40

what are the phases of the menstrual cycle?

Answer 40

- follicular phase - ovulation - luteal phase