Metabolism S7 - Endocrinology

Question 1

Define tropic hormones

Answer 1

A hormone that has another endocrine gland as their target

Question 2

Define trophic hormones

Answer 2

a hormone that stimulates growth in a target tissue

Question 3

Define hormones

Answer 3

Chemical signals produced in endocrine glands or tissue, which travel in the bloodstream causing an effect on other tissues

Question 4

List the classes of hormones

Answer 4

1) Polypeptide hormones (largest group)
2) Glycoprotein hormones
3) Amino acid derivatives
4) Steroids

Question 5

Where is thyrotropin released from?

Answer 5

Hypothalamus

Question 6

What does thyrotrophin stimulate?

Answer 6

Release of thyroid stimulating hormone

Question 7

Where is thyroid stimulating hormone released from?

Answer 7

The anterior pituitary

Question 8

Where is corticotrophin released from?

Answer 8

Hypothalamus

Question 9

What does corticotrophin stimulate?

Answer 9

The release of adrenocorticotrophic hormone

Question 10

Where is adrenocorticotrophic hormone released from?

Answer 10

Anterior pituitary

Question 11

What does somatotrophin stimulate?

Answer 11

Growth hormone

Question 12

Where is growth hormone released from?

Answer 12

Anterior pituitary

Question 13

Where is somatotrophin released from?

Answer 13

Hypothalamus

Question 14

How are steroid hormones inactivated?

Answer 14

Relatively small changes in their chemical structure increases their water solubility. This allows them to be easily excreted from the body in the urine or via the bile

Question 15

How are protein hormones inactivated?

Answer 15

undergo extensive chemical changes and are degraded into amino acids that are then reused

Question 16

What major action does insulin have on carbohydrates, lipids and amino acid metabolism?

Answer 16

• Increased glycogenesis
• Increased glycolysis in liver/adipose tissue
• Increased lipoprotein lipase activity in capillary bed of tissues such as adipose tissue
• Increase amino acid uptake and protein synthesis in liver, muscle and adipose tissue
• Decreased proteolysis in liver, skeletal muscle and adipose tissue
• Decreased glycogenolysis in liver/muscle
• Decreased gluconeogenesis in liver
• Decreased lipolysis in adipose tissue
• Decreased ketogenesis in liver

Question 17

What major action doe glucagon have?

Answer 17

• Increased glycogenolysis
• Increased gluconeogenesis in the liver
• Increased ketogenesis in the liver
• Increased lipolysis in adipose tissue
• Decreased glycogenesis in liver

Question 18

What do β-cells in the islets of Langerhaans produce?

Answer 18

Insulin

Question 19

What do α-cells in the islets of Langerhaans produce?

Answer 19

Glucagon

Question 20

What are the main, general features of control systems in the body?

Answer 20

Communication - Hormones, action potentials
Control centre - Determines set point, analyse input, determines response
Receptor - Signal afferent pathway
Effector - Efferent pathway

Question 21

Give two examples of biological rhythms?

Answer 21

Circadian rhythm - controlled by the suprachiasmatic nucleus in the hypothalamus

Menstrual cycle

Question 22

Describe two methods of hormone transport?

Answer 22

Lipophilic - bound to transport proteins

hydrophilic - free in plasma

Question 23

What type of hormone would bind to cell surface receptors?

Answer 23

polypeptide and glycoprotein hormones

Question 24

What type of hormone binds to intracellular receptors, cytoplasmic or nucleus?

Answer 24

Steroid

Question 25

Where is the control centre for appetite?

Answer 25

Arcuate nucleus in the hypothalamus

Question 26

What hormone stimulates the primary excitatory centre?

Answer 26

Ghrelin - released from empty stomach

Question 27

What is released from primary excitatory centre?

Answer 27

Neuropeptide Y Agouti-related peptide

Question 28

What hormones stimulate the primary inhibitory centres?

Answer 28

Leptin - released from adipose PYY - Released from small intestine Insulin and amylin - released from the pancreas

Question 29

What is released from the primary inhibitory centre?

Answer 29

POMC - a pro-hormone that is cleaved to give: - α-MSH which act on melanocortin 4 receptors which suppresses appetite - ACTH - β-endorphins - reward system, euphoria and tiredness

Question 30

List the features of metabolic syndrome?

Answer 30

Hypertension, impaired glucose tolerance, insulin resistance, dyslipidaemia

Question 31

What is metabolic syndrome?

Answer 31

A common pattern of symptoms that arise in obese patients

Question 32

What is the Developmental Origins of Health and Disease?

Answer 32

Study that the incidence of certain adult disease are related to low birth weight. This suggests that the experience of the foetus in utero during development somehow determines the future health of the individual

Question 33

What is metabolic acidosis?

Answer 33

Metabolic acidosis is a condition that occurs when the body produces excessive quantities of acid or when the kidneys are not removing enough acid from the body

Question 34

Describe results you would see for a glucose tolerance test if glucose utilisation was abnormally slow?

Answer 34

Glucose levels rise but stay abnormally high for a long time and take a while to drop down to normal levels

Question 35

What enzyme is rate limiting in glycogenolysis?

Answer 35

Glycogen phosphorylase

Question 36

Give one example of negative feedback in the body?

Answer 36

- Insulin release in response to hyperglycaemia

Question 37

Give one example of positive feedback in the body?

Answer 37

Blood clotting Ovulation

Question 38

Explain why epigenetic is different to genetic mutation?

Answer 38

Genetic mutation involves changes in the nucleotide sequence (changes in DNA sequence) Epigenetics involves methylation of DNA and changes in histone structure that affect gene transcription