Hormones and the Endocrine System
16 Questions
1 Views

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

Where do free steroid hormones enter and bind within the cell?

  • endoplasmic reticulum
  • mitochondria
  • cytoplasm or nucleus (correct)
  • cell membrane

    • What is the half-life of free and unbound catecholamines such as epinephrine?

  • a minute or less (correct)
  • several hours
  • 30 to 90 minutes
  • 7 to 10 days

    • What is the function of hormones that affect growth and development?

  • normal growth and development of the whole human organism (correct)
  • interact with membrane associated receptors
  • regulate the production, use, and storage of energy
  • exert homeostatic control of metabolic pathways

    • Which hormones are primarily responsible for maintaining homeostasis of blood glucose?

    <p>insulin and glucagon</p> Signup and view all the answers

    What is the primary function of hormones that exert homeostatic control of metabolic pathways?

    <p>maintain homeostasis of metabolic pathways</p> Signup and view all the answers

    What is the primary function of hormones in the body?

    <p>To have a specific regulatory effect on the activity of an organ or organs</p> Signup and view all the answers

    What is the half-life of steroid hormones?

    <p>30 to 90 minutes</p> Signup and view all the answers

    What is the function of hormones that regulate the production, use, and storage of energy?

    <p>regulate the production, use, and storage of energy</p> Signup and view all the answers

    Which of the following hormone classification categories includes insulin?

    <p>Polypeptides or proteins</p> Signup and view all the answers

    What is the term for hormones that exert their action on the cells of origin?

    <p>Autocrine system</p> Signup and view all the answers

    What binds avidly to three binding proteins?

    <p>thyroxine</p> Signup and view all the answers

    How do polypeptide or protein hormones initiate their response?

    <p>By binding to cell membrane receptors</p> Signup and view all the answers

    What is the characteristic of steroid hormones in terms of their solubility?

    <p>They are hydrophobic and insoluble in water</p> Signup and view all the answers

    Which of the following is an example of an endocrine hormone?

    <p>Insulin</p> Signup and view all the answers

    How do endocrine hormones reach their target organs?

    <p>Through the bloodstream</p> Signup and view all the answers

    What is the characteristic of the half-life of polypeptide or protein hormones in plasma?

    <p>It is short (≤10 to 30 minutes)</p> Signup and view all the answers

    Study Notes

    Hormones

    • A hormone is a chemical substance produced in the body that has a specific regulatory effect on the activity of an organ or organs.
    • Hormones are produced at one site in the body and exert their action(s) at distant sites through the endocrine system.
    • Some hormones exert their action locally through the paracrine system, while others exert their action on the cells of origin, regulating their own synthesis and secretion via an autocrine system.

    Classification

    • Hormones are classified into three categories:
      • Polypeptide or protein hormones (e.g., ACTH, insulin, parathyroid hormone)
      • Steroid hormones (e.g., adrenal cortical hormones, androgens, estrogens)
      • Derivatives of amino acids (e.g., thyroxine, catecholamines)

    Polypeptide or Protein Hormones

    • These hormones are generally water-soluble and circulate freely in plasma as whole molecules or as active or inactive fragments.
    • They have a short half-life of ≤10 to 30 minutes in plasma, and their concentration may fluctuate in physiologic and pathologic circumstances.
    • They initiate their response by binding to cell membrane receptors and exciting a "second messenger" system.

    Steroid Hormones

    • These hormones are hydrophobic and insoluble in water.
    • They circulate in plasma, reversibly bound to transport proteins, with only a small fraction free and unbound, available to exert physiologic action.
    • They have a half-life of 30 to 90 minutes in plasma.
    • Free steroid hormones enter the cell by passive diffusion and bind to intracellular receptors in the cytoplasm or nucleus.
    • These hormones are derived from amino acids and are water-soluble.
    • They circulate in plasma bound to proteins (e.g., thyroxine) or free (e.g., catecholamines).
    • They interact with membrane-associated receptors and use a second messenger system.

    Release and Action of Hormones

    • Hormones have physiologic functions that can be broadly categorized into three areas:
      • Affecting growth and development
      • Exerting homeostatic control of metabolic pathways
      • Regulating the production, use, and storage of energy

    Growth and Development

    • Normal growth and development of the human organism is dependent on the complex integrative function of many hormones.
    • Several pituitary hormones are responsible for the growth and development of endocrine glands themselves.

    Homeostatic Control of Metabolic Pathways

    • Hormones are involved in the homeostatic control of diverse and complex metabolic pathways.
    • Insulin and glucagon are the two hormones primarily responsible for maintaining homeostasis of blood glucose levels.

    Studying That Suits You

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

    Quiz Team

    Description

    Learn about hormones, chemical substances produced in the body, and their regulatory effects on organs through the endocrine and paracrine systems.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser