Endocrine 1

Question 1

Name the 8 glands of the Endocrine System

Answer 1

Pituitary Gland, Pineal Gland, Thyroid and Parathyroid Gland, Thymus Gland, Adrenal Gland, Pancreas, Testis (male) and ovaries (female)

Question 2

What is the Endocrine System

Answer 2

a collection of glands that secrete hormones into the blood, which then travels to target cells throughout the body

Question 3

Describe the role of target cells of a given hormone and given an example

Answer 3

only the target cells for a given hormone have receptors that bind and recognise that hormone
for example, thyroid-stimulating hormone (TSH) binds to receptors on cells of the thyroid gland but not to other cells as they don’t have TSH receptors

Question 4

In which 3 ways is hormone secretion regulated

Answer 4

signals from the nervous system
chemical changes in the blood
other hormones

Question 5

What is the main function of the Endocrine System

Answer 5

to maintain homeostasis by monitoring the environment of the body and responding to change

Question 6

Name 4 things the Endocrine System can do

Answer 6

regulate the activity of smooth muscle, cardiac muscle and some glands
alter metabolism
initiate growth and development
influence reproductive processes

Question 7

What does the endocrine system work on the process of

Answer 7

positive and negative feedback loop

Question 8

Give an example of a positive feedback loop

Answer 8

during childbirth = oxytocin stimulates contractions of the uterus, uterine contractions = stimulate more oxytocin = more uterine contractions

Question 9

Give 2 details about positive feedback loops

Answer 9

usually occur when the body wants a quick response, cannot be maintained for long periods of time

Question 10

Give an example of a negative feedback loop - where patient is too hot and so needs to cool down

Answer 10

target set point is 37 degrees - a rise above this is sensed by the hypothalamus = sweat = sweat evaporates and heat is removed, vasodilation = blood vessels are nearer skin surface = heat lost by convection
causes a temp drop

Question 11

Give an example of a negative feedback loop - where patient is too cold and so needs to warm up

Answer 11

need to inhibit above responses, develop goose bumps to ‘pull’ skin in to conserve heat, vasoconstriction = prevents heat loss from the blood at the skin surface, body temp will increase until set body temp reached

Question 12

Describe the role of the pituitary gland

Answer 12

regulates other endocrine glands, secretes growth hormone

Question 13

Describe the role of the thyroid gland and the 4 parathyroid glands

Answer 13

regulates metabolic rate

Question 14

Describe the role of the thymus gland

Answer 14

assists in development of the immune system

Question 15

Describe the role of the 2 adrenal glands

Answer 15

regulates fluid and sodium balance, emergency warning system under stress

Question 16

Describe the role of the 2 ovaries/2 testes

Answer 16

controls development of secondary sex characteristics and functioning of sex organs

Question 17

Describe the role of the pancreas/pancreatic islets

Answer 17

helps regulate blood sugar

Question 18

Describe the role of the pineal gland

Answer 18

believed to regulate biorhythms and moods and stimulate the onset of puberty

Question 19

Describe the link between the hypothalamus and the pituitary gland and where each is found

Answer 19

the pituitary gland is controlled by the hypothalamus, the hypothalamus sits in the brain below the thalamus, the pituitary gland lies below in the pituitary fossa

Question 20

Which 6 hormones are released by the anterior pituitary gland

Answer 20

Human Growth Hormones - regulates growth
Thyroid-Stimulating Hormone - controls thyroid secretions
Luteinising Hormone and Follicle Stimulating Hormone - regulates the menstrual cycle, maintain pregnancy, prepare mammary glands for lactation
Adrenocorticotropic Hormone - stimulates adrenal glands
Prolactin - initiates milk production
Melanocyte-Stimulating Hormone - thought to influence brain activity

Question 21

Which 2 hormones are stored and released by the posterior pituitary gland

Answer 21

Oxytocin - enhances contractions during childbirth, stimulates milk release after delivery, responsible for parental caretaking behaviour toward young offspring
Antidiuretic Hormone - determines the amount of water excreted from the body

Question 22

Describe Antidiuretic Hormone (ADH) and high blood osmotic pressure and low blood volume

Answer 22

high blood osmotic pressure/ low blood volume due to dehydration/haemorrhage/diarrhoea/excessive sweating stimulates the hypothalamus to synthesise and release ADH

ADH targets kidneys = retain more water = decreases urine output, sudoriferous (sweat) glands reduce their activity thus reducing water loss by perspiration from the skin
Smooth muscle in blood vessel walls - constricts lumen of the vessel and increasing blood pressure

Question 23

Describe ADH and low blood osmotic pressure and high blood volume

Answer 23

low osmotic pressure/high blood volume = inhibits the hypothalamus = reduces/stops ADH secretion = kidneys then retain less water by forming a larger volume of urine = secretory activity of sweat glands increases/arterioles dilate = blood volume and osmotic pressure of bodily fluids return to normal

Question 24

Give 9 stimulants of ADH

Answer 24

Pain, Stress, Trauma, Anxiety, Acetylcholine, Nicotine, Morphine, Tranquilizers, Some anaesthetics

Question 25

What causes Diabetes Insipidus

Answer 25

Hypo secretion of ADH or non-functional ADH receptors

Question 26

Describe the thyroid gland

Answer 26

butterfly-shaped, located in the anterior neck, inferior to the larynx, upper border is level at C5, lower border is level at T1

Question 27

Describe how the thyroid gland uses iodine and its roles

Answer 27

uses iodine from the diet to produce the hormones thyroxine (T4) and triiodothyronine (T3), it produces calcitonin - important in maintenance of serum calcium level, helps control metabolism, heart rate and body temp growth and development, increased secretion of the thyroid hormones caused by cold environment, hypoglycaemia, high altitude and pregnancy

Question 28

Describe the Parathyroid Glands

Answer 28

4 small, rounded masses partially embedded in the posterior surfaces of the thyroid gland

Question 29

Describe the role of the parathyroid glands

Answer 29

produce parathyroid hormone (PTH) that
regulates calcium, magnesium and phosphate in the blood and bones
increases the number and activity of osteoclasts

Question 30

Describe the Pancreas

Answer 30

located in the curve of the duodenum,
Endocrine Function - secreting glucagon, insulin, somatostatin and pancreatic polypeptide from islets of langerhans
Exocrine Function - secreting digestive enzymes into the duodenum

Question 31

Describe the difference between glucagon and insulin

Answer 31

Glucagon = to increase blood glucose when necessary
Insulin = to reduce blood glucose when necessary

Question 32

Describe the regulation of Glucagon and Insulin Secretion

Answer 32

Glucagon causes the liver to increase glucose production = this is released into the blood and blood glucose level rises = if blood glucose level continues to rise = hyperglycaemia = inhibits release of glucagon = hyperglycaemia stimulates the secretion of insulin by the pancreatic islets = reduces glucose levels causing blood glucose level to fall= drops too low then stimulates release of glucagon

Question 33

Describe the links between digestion and exercise with glucagon and insulin

Answer 33

Digestion provides strong stimulation of insulin release

Exercise which causes blood glucose level to fall will stimulate glucagon secretion