Human Physiology Quick Notes

Questions and Answers

What is the role of Gonadotrophin releasing hormone (GnRH) in the body?

Promotes the growth of body fluids

Decreases the rate of neural coordination

Stimulates the secretion of gonadotrophins (correct)

Inhibits the release of melatonin

What hormone does the pineal gland secrete?

Somatostatin

Growth hormone

Melatonin (correct)

Gonadotrophin

Where is the pineal gland located in the human body?

On the dorsal side of the forebrain (correct)

In the temporal lobe

Attached to the pituitary gland

On the ventral side of the hindbrain

Which hormone inhibits the release of growth hormone from the pituitary?

Somatostatin Signup and view all the answers

What does melatonin regulate in the body?

24-hour diurnal rhythm Signup and view all the answers

What is the function of thymosins secreted by the thymus gland?

Differentiation of T-lymphocytes Signup and view all the answers

Which hormone is secreted by the posterior pituitary gland?

Oxytocin Signup and view all the answers

How does parathyroid hormone (PTH) affect calcium levels in the blood?

Increases calcium levels Signup and view all the answers

What is a potential consequence of hypothyroidism during pregnancy?

Defective development of the baby Signup and view all the answers

What causes goitre associated with hypothyroidism?

Deficiency of iodine Signup and view all the answers

Which gland is responsible for the direct neural regulation of the posterior pituitary?

Hypothalamus Signup and view all the answers

What type of hormone is secreted by the parathyroid glands?

Peptide hormone Signup and view all the answers

What is the anatomical location of the thymus gland?

Between the lungs behind the sternum Signup and view all the answers

What hormone is primarily responsible for regulating glucose levels in the body?

Cortisol Signup and view all the answers

What is the main consequence of prolonged hyperglycemia in the body?

Formation of ketone bodies Signup and view all the answers

Which hormone produced by the kidneys stimulates erythropoiesis?

Erythropoietin Signup and view all the answers

Which type of hormone generates secondary messengers upon binding to its receptor?

Peptide hormones Signup and view all the answers

What role does gastrin play in the gastrointestinal tract?

Stimulates secretion of HCl and pepsinogen Signup and view all the answers

Which of the following hormones has a function related to kidney function?

Aldosterone Signup and view all the answers

What is a characteristic feature of steroid hormones?

They do not generate secondary messengers Signup and view all the answers

What effect does ANF have on blood pressure?

Decreases blood pressure Signup and view all the answers

What condition is characterized by stunted growth, mental retardation, and low intelligence quotient?

Cretinism Signup and view all the answers

Which hormone increases blood calcium levels by stimulating reabsorption in the renal tubules?

Parathyroid hormone (PTH) Signup and view all the answers

What is the primary function of glucagon in the body?

To promote glycogenolysis Signup and view all the answers

Exopthalmic goitre is a symptom commonly associated with which condition?

Hyperthyroidism Signup and view all the answers

What type of hormone is insulin classified as?

Hypoglycemic hormone Signup and view all the answers

Which adrenal gland structure secretes catecholamines in response to stress?

Adrenal medulla Signup and view all the answers

Which of the following statements about the adrenal cortex is true?

It is involved in carbohydrate metabolism. Signup and view all the answers

What role does thyrocalcitonin (TCT) play in the body?

It helps regulate blood calcium levels. Signup and view all the answers

Study Notes

Chemical Coordination and Integration

Hypothalamus: Produces Gonadotrophin releasing hormone (GnRH), stimulating pituitary gonadotrophin release. Somatostatin inhibits growth hormone release.
Pituitary Gland: Comprised of anterior (Adenohypophysis) and posterior (Neurohypophysis) lobes. It secretes multiple hormones:
- Growth hormone (GH), Prolactin (PRL), Thyroid-stimulating hormone (TSH), Adrenocorticotrophic hormone (ACTH)
- Luteinizing hormone (LH), Follicle-stimulating hormone (FSH)
- Posterior lobe releases Oxytocin and Vasopressin.
Pineal Gland: Located in the forebrain; secretes melatonin, regulating diurnal rhythms and influencing sleep patterns.
Thymus: Situated between the lungs; critical for immune system development. Secretes thymosins, promoting T-lymphocyte differentiation for cell-mediated immunity.
Thyroid Gland: Consists of two lobes near the trachea.
- Synthesizes thyrocalcitonin (TCT) to regulate blood calcium levels.
- Iodine deficiency causes hypothyroidism, leading to goitre and developmental defects. Exophthalmic goitre (Graves' disease) indicates hyperthyroidism with symptoms of increased metabolism and weight loss.
Parathyroid Gland: Secretes parathyroid hormone (PTH), which elevates blood calcium levels. PTH promotes bone resorption and enhances renal and digestive calcium absorption.
Adrenal Gland: Contains adrenal medulla and cortex.
- Medulla: Releases adrenaline and norepinephrine, responsible for fight-or-flight response.
- Cortex: Produces corticosteroids, with cortisol as the main glucocorticoid; regulates metabolism and electrolytes. Aldosterone controls sodium and potassium balance.
Pancreas: Hosts Islets of Langerhans with α-cells (glucagon) and β-cells (insulin).
- Glucagon raises blood sugar by stimulating glycogenolysis in liver cells.
- Insulin lowers blood sugar by enhancing glucose uptake and conversion to glycogen.

Hormones of Other Organs

Heart: Atrial Natriuretic Factor (ANF) reduces blood pressure.
Kidney: Erythropoietin stimulates red blood cell production.
Gastrointestinal Tract:
- Gastrin promotes HCl and pepsinogen secretion.
- Secretin stimulates bicarbonate and water secretion.
- Cholecystokinin (CCK) enhances pancreatic enzyme and bile secretion.
- Gastrointestinal Inhibitory Peptide (GIP) inhibits gastric activities.

Mechanism of Hormone Action

Protein Hormones: Water-soluble, generate second messengers (e.g., cyclic AMP) upon binding to plasma membrane receptors (e.g., insulin, glucagon).
Steroid Hormones: Lipid-soluble, directly regulate gene expression without forming secondary messengers (e.g., cortisol, testosterone).

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge of human physiology with this concise quiz. Covering key concepts and essential information, these one-page notes will help you prepare efficiently. Challenge yourself and enhance your understanding of human body functions.