BuyFindarrow_forward

Biology: The Dynamic Science (Mind...

4th Edition
Peter J. Russell + 2 others
ISBN: 9781305389892

Solutions

Chapter
Section
BuyFindarrow_forward

Biology: The Dynamic Science (Mind...

4th Edition
Peter J. Russell + 2 others
ISBN: 9781305389892
Textbook Problem

Researchers measured prolactin and growth hormone in the blood plasma of six subjects at regular intervals over a 24-hour period. The investigators were interested in determining if the levels of these two hormones cycle over a 24-hour period. The Figure presents the results of their experiments, with the y axis values showing the amount of each hormone expressed as a percentage of the 24-hour mean value, and each point showing the average of the six subjects’ levels.

Chapter 42, Problem 4ITD, Researchers measured prolactin and growth hormone in the blood plasma of six subjects at regular

FIGURE Mean concentrations of prolactin and growth hormone in plasma, averaged for six subjects and expressed as a percentage of the average concentrations measured for the 24-hour period.

Do the results support the hypothesis that the changes in prolactin level over a 24-hour period are associated with the sleep–wake cycle?

Source: From J. F. Sassin et al. 1972. Human prolactin: 24-hour pattern with increased release during sleep. Science 177:1205–1207.

Summary Introduction

To review:

Whether the results shown in the figure, support the fact that changes in prolactin level over a 24-hour period are related to the sleep–wake cycle.

Introduction:

The mammary gland in humans is known as the breast and under the influence of milk-producing hormone, it produces milk. The prolactin is the main hormone involved in the production of the milk. Prolactin hormone is released by the anterior lobe of pituitary gland. Other hormones that influence lactation are human placental lactogen, estrogen, prolactin, progesterone, oxytocin, follicle stimulating hormone, luteinizing hormone, human chorionic gonadotropin, growth hormone, as well as adrenocorticotropic hormone.

Explanation

The levels of prolactin fluctuate during the whole 24-hour period. In the day, after 12’ O clock, the levels of prolactin increases and subsequently decreases after every hour. After 4’O clock in the evening, the level increases till 9’O clock and then it falls again. It reaches its peak, maximal secretion during the sleep period.

The sleep period starts from 12’O clock in the night and lasts till 8 a...

Still sussing out bartleby?

Check out a sample textbook solution.

See a sample solution

The Solution to Your Study Problems

Bartleby provides explanations to thousands of textbook problems written by our experts, many with advanced degrees!

Get Started

Additional Science Solutions

Find more solutions based on key concepts

Show solutions add

In what way has biotechnology had an impact on agriculture in the United States?

Human Heredity: Principles and Issues (MindTap Course List)

How does the CNO cycle differ from the proton-proton chain? How is it similar?

Horizons: Exploring the Universe (MindTap Course List)

Chemical digestion of all nutrients mainly occurs in which organ? a. mouth b. stomach c. small intestine d. lar...

Nutrition: Concepts and Controversies - Standalone book (MindTap Course List)

Why is the oxidation of fatty acids referred to as -oxidation?

Chemistry for Today: General, Organic, and Biochemistry

Rank the electric potentials at the four points shown in Figure OQ25.7 from largest to smallest.

Physics for Scientists and Engineers, Technology Update (No access codes included)

Match the term listed in Column A with its definition from Column B

Nutrition Through the Life Cycle (MindTap Course List)