Endocrine System Overview

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What hormone is secreted by β - cells?

  • Insulin (correct)
  • Glucagon
  • Testosterone
  • Estrogen

Which condition is caused by insufficient secretion of insulin?

  • Diabetes mellitus (correct)
  • Hypoglycemia
  • Hyperthyroidism
  • Goitre

What hormone is primarily secreted by Leydig cells?

  • Insulin
  • Testosterone (correct)
  • Estrogen
  • Progesterone

Which hormone is secreted by the pineal gland?

<p>Melatonin (A)</p> Signup and view all the answers

What role does thyrocalcitonin play in the body?

<p>Lowers calcium levels in blood plasma (A)</p> Signup and view all the answers

Which gland secretes both T3 and T4 hormones?

<p>Thyroid gland (D)</p> Signup and view all the answers

What characterizes hypothyroidism?

<p>Goitre development (A), Low levels of iodine (B)</p> Signup and view all the answers

What is the primary function of hormones in the body?

<p>To regulate physiological processes (C)</p> Signup and view all the answers

What is the primary function of releasing hormones from the hypothalamus?

<p>Stimulate the release of hormones from the pituitary gland (B)</p> Signup and view all the answers

Which statement correctly contrasts hormonal control with nervous control?

<p>Hormonal control is not affected by previous experiences. (C)</p> Signup and view all the answers

Which types of glands discharge their secretions directly into the blood?

<p>Endocrine glands (C)</p> Signup and view all the answers

What disease can result from hyposecretion of the adrenal cortex?

<p>Addison's Disease (D)</p> Signup and view all the answers

What role does aldosterone play in the body?

<p>Maintains sodium and potassium levels in blood (A)</p> Signup and view all the answers

Which type of cells in the pancreas are responsible for secreting glucagon?

<p>Alpha cells (D)</p> Signup and view all the answers

Which gland secretes catecholamines, including adrenaline?

<p>Adrenal medulla (B)</p> Signup and view all the answers

What characterizes the effects of hormones compared to nervous impulses?

<p>Hormones can have long-lasting effects. (A)</p> Signup and view all the answers

What condition is associated with low secretion of growth hormone?

<p>Dwarfism (C)</p> Signup and view all the answers

Which hormone is responsible for milk formation and the growth of the mammary glands?

<p>Prolactin (B)</p> Signup and view all the answers

The hormone responsible for the reabsorption of water from the kidneys is called?

<p>Vasopressin (B)</p> Signup and view all the answers

Which hormone induces ovulation from Graafian follicles?

<p>Luteinizing hormone (A)</p> Signup and view all the answers

What is the primary function of thymosins produced by the thymus gland?

<p>Producing T-lymphocytes (A)</p> Signup and view all the answers

Which of the following glands is involved in the secretion of hormones that regulate metabolism?

<p>Thyroid gland (A)</p> Signup and view all the answers

Hormones generally have which characteristic regarding their action?

<p>They generally have a slower onset but longer-lasting effects. (D)</p> Signup and view all the answers

What role does a feedback mechanism play in hormone regulation?

<p>It regulates the action and levels of hormones. (C)</p> Signup and view all the answers

Flashcards

Hormones

Chemical messengers that regulate bodily functions, impacting specific target cells, tissues, and organs.

Endocrine Glands

Glands that release their secretions directly into the bloodstream, without ducts, often called ductless glands.

Exocrine Glands

Glands that release their secretions into ducts, which then carry them to their target area.

Adrenal Medulla

The inner part of the adrenal gland that secretes adrenaline (epinephrine) and noradrenaline (norepinephrine), also known as catecholamines, which are crucial for responding to stress and emergencies.

Signup and view all the flashcards

Adrenal Cortex

The outer part of the adrenal gland that secretes corticoids, including glucocorticoids like cortisol, which regulate carbohydrate metabolism, and mineralocorticoids like aldosterone, which maintain sodium and potassium balance.

Signup and view all the flashcards

Addison's Disease

Condition caused by insufficient secretion from the adrenal cortex, leading to various disturbances like fatigue, low blood pressure, and skin discoloration.

Signup and view all the flashcards

Cushing's Syndrome

Condition caused by excessive secretion from the adrenal cortex, leading to symptoms like weight gain, muscle weakness, and high blood pressure.

Signup and view all the flashcards

Islets of Langerhans

Specialized clusters of cells within the pancreas that produce hormones like insulin and glucagon, crucial for regulating blood sugar levels.

Signup and view all the flashcards

Dwarfism

A deficiency of growth hormone, resulting in stunted height.

Signup and view all the flashcards

Acromegaly

Excess growth hormone production, primarily affecting bones in the hands, feet, and face.

Signup and view all the flashcards

Prolactin

Hormone produced by the pituitary gland, crucial for milk production and development of mammary glands.

Signup and view all the flashcards

Thyroid Stimulating Hormone (TSH)

Hormone secreted by the pituitary gland, stimulating the thyroid gland to produce thyroxine.

Signup and view all the flashcards

Adrenocorticotrophic Hormone (ACTH)

Hormone produced by the pituitary gland, regulating the adrenal cortex's secretion of glucocorticoids.

Signup and view all the flashcards

Gonadotrophic Hormones

A group of hormones produced by the pituitary gland that influence the sex organs.

Signup and view all the flashcards

Oxytocin

Hormone from the posterior pituitary gland, responsible for uterine contraction and milk ejection.

Signup and view all the flashcards

Vasopressin

Hormone from the posterior pituitary gland, controlling water reabsorption by the kidneys.

Signup and view all the flashcards

Insulin

A hormone that lowers blood glucose levels by promoting glucose uptake and storage by cells.

Signup and view all the flashcards

Glucagon

A hormone that raises blood glucose levels by stimulating the liver to release stored glucose.

Signup and view all the flashcards

Diabetes Mellitus

A condition characterized by high blood glucose levels due to insufficient insulin production or action.

Signup and view all the flashcards

Hypoglycemia

A condition characterized by low blood glucose levels, often caused by excessive insulin production.

Signup and view all the flashcards

Testosterone

A hormone produced by the testes, primarily responsible for the development of male secondary sexual characteristics.

Signup and view all the flashcards

Estrogen

A hormone produced by the ovaries, involved in the development of female secondary sexual characteristics.

Signup and view all the flashcards

Progesterone

A hormone produced by the ovaries, involved in promoting the development of the uterine lining and preparing the breasts for milk production.

Signup and view all the flashcards

Hypothalamus

The control center for the endocrine system, responsible for releasing hormones that regulate the pituitary gland.

Signup and view all the flashcards

Study Notes

Hormones

  • Hormones are chemical messengers that regulate physiological processes in living organisms.
  • Hormones act on specific target cells, tissues, and organs.

Endocrine Glands

  • Endocrine glands secrete hormones directly into the bloodstream.
  • Exocrine glands secrete substances into ducts.
    • Examples of exocrine glands include salivary glands, sebaceous glands.
  • Major endocrine glands include pituitary, pineal, thyroid, adrenal, pancreas, parathyroid, thymus, and gonads.
  • Other organs, including the GI tract, liver, kidneys, and heart, also produce hormones.

Differences Between Hormonal and Nervous Control

Feature Hormonal Control Nervous Control
Transmission Chemically through blood Electro-chemically through nerve fibres
Speed Slow Rapid
Target Different organs Specific organs
Effects of previous experience Not affected Affected
Duration Long-lasting and short-lasting Short-lasting

Adrenal Glands

  • Divided into adrenal medulla and adrenal cortex.
  • Adrenal medulla secretes adrenaline (epinephrine) and noradrenaline (norepinephrine), which are called catecholamines (emergency hormones).
  • Adrenal cortex secretes corticoids, which include glucocorticoids (regulate carbohydrate metabolism, e.g., cortisol) and mineralocorticoids (regulate sodium and potassium levels, e.g., aldosterone).

Hyposecretion and Hypersecretion

  • Hyposecretion: Less secretion from an endocrine gland (e.g., Addison's Disease, insufficient insulin secretion leads to Diabetes Mellitus).
  • Hypersecretion: Increased secretion (e.g., Cushing's syndrome, over-secretion of insulin leads to hypoglycemia).

Pancreas

  • Islets of Langerhans contain alpha (α) and beta (β) cells.
  • Alpha cells secrete glucagon.
  • Beta cells secrete insulin.

Testis

  • Leydig cells secrete androgens (mainly testosterone).
  • Testosterone is involved in spermatogenesis and male secondary sexual characteristics.

Ovary

  • Secretes estrogen and progesterone.
  • Estrogen develops female secondary sexual characteristics.
  • Progesterone affects mammary glands and milk secretion.

Hypothalamus

  • Contains neurosecretory cells that produce releasing and inhibiting hormones.
  • These hormones regulate the synthesis and secretion of pituitary hormones.

Pineal Gland

  • Secretes melatonin which regulates the body's rhythm.

Thyroid Gland

  • Secretes tetraiodothyronine (thyroxine, T4) and triiodothyronine (T3).
  • Iodine deficiency can lead to hypothyroidism (goiter, cretinism, myxedema).
  • High iodine levels can lead to hyperthyroidism (increased metabolic rate).

Parathyroid Gland

  • Regulates calcium levels in the blood (increases reabsorption in renal tubules and digested food).

Pituitary Gland

  • Divided into adenohypophysis (anterior pituitary) and neurohypophysis (posterior pituitary).
  • Anterior pituitary: produces growth hormone, prolactin, thyroid stimulating hormone, adrenocorticotrophic hormone, gonadotrophic hormones (luteinizing hormone and follicle stimulating hormone), and melanocyte-stimulating hormone (MSH)
  • Posterior pituitary: produces oxytocin and vasopressin (antidiuretic hormone).

Other Hormones

  • Prolactin: Involved in mammary gland growth and milk production.
  • Thyroid-stimulating hormone: Stimulates thyroxine secretion.
  • Adrenocorticotropic hormone: Stimulates glucocorticoid secretion.
  • Gonadotrophic hormones: Regulate gonadal function.
  • Melanocyte-stimulating hormone assists in skin pigmentation.
  • Oxytocin helps in uterine contraction and milk ejection
  • Vasopressin or antidiuretic hormone helps reabsorb water by tubules
  • Hyperglycaemia: Increased blood glucose; involves glucagon and diabetes mellitus
  • Hypoglycemia: Reduced blood glucose; involves insulin

Characteristics of Hormones

  • Act as chemical messengers.
  • Secreted by living cells, tissues, or organs (glands).
  • Secreted in small quantities.
  • Act on specific target sites.
  • Generally slow but long-lasting effects.
  • Either accelerate or inhibit a reaction.

Studying That Suits You

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

Quiz Team

Related Documents

Endocrine System (Grade 10) PDF

More Like This

Système endocrinien et hormones
42 questions

Système endocrinien et hormones

TimeHonoredFlute7615 avatar
TimeHonoredFlute7615
Sistema Endocrino y Hormonas
48 questions

Sistema Endocrino y Hormonas

GlisteningMossAgate313 avatar
GlisteningMossAgate313
The Endocrine System Overview
17 questions

The Endocrine System Overview

IngeniousWillow5306 avatar
IngeniousWillow5306
Endocrine System Quiz
42 questions

Endocrine System Quiz

CheaperHibiscus4554 avatar
CheaperHibiscus4554
Use Quizgecko on...
Browser
Open
Browser
Browser