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Lab 14

Endocrine System

Laboratory Objectives

Identify the location of the primary endocrine organs.

List the hormones produced by the endocrine organs.

Relate the mechanisms of up-regulation and down-regulation to the cellular

sensitivity to hormones.

Illustrate examples or hormonal positive- and negative-feedback mechanisms.

Describe the cellular activation mechanisms of lipid-soluble and water-soluble

hormones.

Describe the anatomical and physiological relationship of the hypothalamus and

pituitary.

Relate the secretion releasing-hormones to the secretion of hormones from the

anterior lobe of the pituitary.

Describe the effects of a human-growth hormone hypersecretion disorder.

Describe the structure of the pancreatic islets.

Relate the terms glycogenolysis and gluconeogenesis to blood glucose regulation.

Relate the dysfunction of insulin production or action to the disorder diabetes

mellitus.

Describe the relationship of parathyroid hormone and calcitonin

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Activity 1: PowerAnatomy

Navigation: WileyPlus > Lab Exercise 25. Endocrine System > PowerAnatomy > Table of

Contents > 10 - The Endocrine System

Complete exercise A - Hormone Abbreviations by clicking on the “Exercises” link in

bottom left-corner.

Complete exercise B - Location of Endocrine Glands

Complete review assignment 1 - Main Endocrine Organs and Hormones by clicking

on the “Review” link

Complete review assignment 2 - Hormones

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Activity 2: Pituitary Gland

Navigation: WileyPlus > Lab Exercise 25. Endocrine System > Do > Activity 2: The Pituitary

Gland

1. Describe the structural and functional relationship of the hypothalamus with the

two lobes of the pituitary gland.

2. The pituitary is often referred to as the “master gland”. Is that true, or is the

hypothalamus a better fit?

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Activity 3: Hormone Regulation

Navigation: WileyPlus > Lab Exercise 25. Endocrine System > See > Animation -

Introduction to Hormonal Regulation, Secretion, and Concentration, > Sections 3.1- 3.3

1. Define and provide an example of a target cell.

2. How can a target cell increase its sensitivity to a hormone?

3. How does a target cell decrease its sensitivity to a hormone?

4. Relate insulin-resistance in type II diabetes to the process of down-regulation.

5. What would be the relationship if a patient had a high fasting blood glucose level

concurrent with a high fasting blood insulin level?

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > See > Animation -

Introduction to Hormonal Regulation, Secretion, and Concentration, > Sections 4.1-4.3

1. How do hormones regulate secretions from other cells?

2. Describe the origin and secretion of oxytocin. Relate the function of oxytocin to a

positive-feedback mechanism.

3. Relate the actions of the insulin and glucogon to glucose regulation by negative-

feedback.

Activity 4: Hormone Regulation

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > See > Animation -

Mechanisms of Hormone Action > Sections 2.1-2.3

1.If a hormone is lipid-soluble, what does that mean about its transport in the blood

and its mechanism to stimulate a target cell?

2. Where are the receptors for lipid-soluble hormones located?

3. If a hormone is water-soluble (lipid insoluble), what how does that relate to its

transport in the blood and mechanism to stimulate a target cell?

4. Where are the receptors for water soluble hormones located?

5. Why is adenylate cyclase referred to as an amplifier enzyme?

6. In easy-to-understand terms, what does it mean when a protein has been

phosphorylated by a kinase?

Activity 5: Hormone Action

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > Do > Homeostatic Imbalance:

The Case of the Growing Girl

1. What disorder caused the hypersecretion of HGH?

2. Why does the patient have a high blood glucose level?

3. Why does the patient’s intracranial pressure increase in this disorder?

Activity 6: The Case of the Growing Girl

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > Do > Activity 5: The Pancreas

1. What is the anatomical location of the pancreas in the abdominal cavity? .

2. What is the structure of the pancreatic islets?

3. Compare the location and function of the pancreatic islets and acini.

Activity 7: The Pancreas

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > Do > Interactive Exercise:

Glucose Regulation Feedback Loop

1. Compare the terms glycogenolysis and gluconeogenesis.

2. What is meant by the humoral-control of hormone release?

Activity 8: Glucose Regulation

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > Do > Homeostatic Imbalance:

The Case of the Girl with Fruity Breath

1. What is the cause of the patient’s frequent urination?

2. How does this patient’s condition differ from diabetes insipidus?

3. Why is the patient’s blood acidic?

4. Why is weight loss a common symptom of diabetes?

5. In type I diabetes, what is the common cause of beta-cell destruction?

Activity 9: The Case of the Girl with Fruity Breath

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Navigation: WileyPlus > Lab Exercise 25. Endocrine System > Do > Interactive Exercise:

Calcium Homeostasis

1. Define hypocalcemia and hypercalcemia.

2. Describe the location and hormones secreted from the following:

a. Follicular cells of the thyroid

b. Parafollicular cells of the thyroid

c. Principal cells of the parathyroid

3. Relate the change in bone density to the function of parathyroid hormone and

calcitonin.

Activity 10: Parathyroid and Calcitonin

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1. To relate hormones to disease states, complete the “Operations or Conditions”

under the review link in PowerAnatomy

2. Plasma protein levels are frequently reported in g/dl, plasma glucose in mg/dl.

Hormones, vitamins, and some medications are reported in international units (IU).

For example, the normal fasting level of insulin is 5-27 µIU/ml. What is an IU?

3. The kidneys are targets of parathyroid hormone (PTH). Why would PTH target

the kidney cells? Think about the hormone’s action.

4. Pituitary Surgery Video:

http://streaming.weber.edu:8080/ramgen/wsuonline/hs1110/pituitary.rm

Additional Activities: