Biology
Biology
5th Edition
ISBN: 9781260487947
Author: BROOKER
Publisher: MCG
bartleby

Videos

Textbook Question
Book Icon
Chapter 50, Problem 1TY

Which is the defining feature of hormones?

  1. a. They are only produced in endocrine glands.
  2. b. They are secreted into the blood, where they may reach one or more types of distant target cells, thereby altering cell function throughout the body.
  3. c. They are released only by neurons.
  4. d. They are never released by neurons.
  5. e. They are secreted into ducts, where they diffuse to another nearby gland or other structure.
Expert Solution & Answer
Check Mark
Summary Introduction

Introduction: The chemical messengers that are produced in the body are called hormones. Hormones act on target tissues as their secretions are directly poured in the bloodstream. Usually, endocrine glands constitute the hormone-producing cells. These hormone-producing cells make up the endocrine system.

Answer to Problem 1TY

Correct answer: Hormones are chemical messengers that are directly secreted into the bloodstream. In the bloodstream, they reach the target cells, thereby alter the functioning of the cells throughout the body of an individual. Hence, the correct answer is option b.

Explanation of Solution

Reason for correct answer:

Hormones are chemical messengers that may be produced by endocrine and exocrine glands. Endocrine glands in the body produce hormones which control functions of various parts and organs present in the body of an individual. These endocrine glands are ductless glands due to which they pour their secretions directly in the bloodstream. Hormones released by the ductless glands reach the target cell or tissue, and alter their function throughout the body of an individual.

Option b. is given as “They are secreted into the blood where they may reach one or more types of distant target cells, thereby altering cell function throughout the body”.

Hormones are chemical secretions released by endocrine glands directly in the bloodstream and alter the function of the target tissue or cell. Hence, the correct answer is option b.

Reasons for the incorrect answer:

Option a. is given as, “They are only produced in endocrine glands”.

Hormones are chemical messengers which are produced usually in endocrine glands. However, secretions of the pancreas are produced in endocrine as well as exocrine glands. Thus, hormones are not exclusively produced in endocrine glands. Hence option a. is incorrect.

Option c. is given as, “They are released only by neurons”.

The secretions of the neurons are called neurotransmitters. These neurotransmitters are not hormones but constitute sensory stimulus which in turn activates the endocrine system to produce hormones. Thus, hormones are the secretions of exocrine and endocrine glands. Hence, option c. is incorrect.

Option d. is given as, “They are never released by neurons”.

Neurons released neurotransmitters stimulate the endocrine glands to secrete hormones. Hormones are poured directly into the bloodstream to act on the target tissue by the ductless endocrine glands. Hence, option d. is incorrect.

Option e. is given as; “They are secreted into ducts where they diffuse another nearby gland or structure”.

Ductless endocrine glands put their secretions known as hormones directly into the bloodstream. These hormones are transported to a distant site where they act on the target tissue to produce their action. However, exocrine glands have ducts which produce the hormone in the local environment. Hence, option e. is incorrect.

Hence, the options a., c., d., and e. are incorrect.

Conclusion

Hormones are chemical messengers secreted by endocrine glands. The endocrine glands pour these hormones directly in the bloodstream where they act on the target tissue to produce an action.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Which is the defining feature of hormones?a. They are only produced in endocrine glands.b. They are secreted into the blood, where they may reach one or moretypes of distant target cells, thereby altering cell function throughoutthe body. c. They are released only by neurons.d. They are never released by neurons.e. They are secreted into ducts, where they diffuse to another nearbygland or other structure.
What is the main difference between organizing effects and activating effects of hormones?A. Organizing effects are long-lasting, whereas activating effects are temporary.B. Organizing effects alter brain activity, whereas activating effects alter other parts of the body.C. Organizing effects are excitatory, whereas activating effects are inhibitory.D. Organizing effects depend on estrogens, whereas activating effects depend on androgens.
What casuses a cell to be sensative to particular hormone? A. all cells are exposed to the endocrine signals so they are all sensivtive to it B.the presense of receptors for that hormone c. the shorter the distance between the source cell and the target cell, the more sensitive the target cell is to the hormone.
Knowledge Booster
Background pattern image
Biology
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
  • Text book image
    Concepts of Biology
    Biology
    ISBN:9781938168116
    Author:Samantha Fowler, Rebecca Roush, James Wise
    Publisher:OpenStax College
Text book image
Concepts of Biology
Biology
ISBN:9781938168116
Author:Samantha Fowler, Rebecca Roush, James Wise
Publisher:OpenStax College
Great Glands - Your Endocrine System: CrashCourse Biology #33; Author: CrashCourse;https://www.youtube.com/watch?v=WVrlHH14q3o;License: Standard Youtube License