Endocrine System WorksheetBiology 100C

1. What is an Endocrine Gland?

This is a gland that secretes hormones

2. Endocrine glands are also called ___ductless glands____________ because they secrete their chemical messengers into _____body fluids_(usually the blood)_______.

3. The chemical messenger secreted by an endocrine gland is called a

Hormone

4. How does an Endocrine Gland differ from an Exocrine Gland?

Exocrine glands secrete fluid into a duct which conveys the products to the location

5. What are Neurosecretory Cells and why do they show that the endocrine system and the nervous system are related structurally, chemically, and functionally?

They are specialized nerve cells that secrete hormones. Several chemicals serve as both hormones and neurotransmitters.

6. Name three different local regulators, tell what the chemical composition is for each one, and give one function for each local regulator.

Nitric Oxide (NO) – secreted by neurons as a neurotransmitter, by WBC kills bacteria and cancer cells, by endothelia cells in blood vessels causes smooth muscle to relax.

Growth Factors – these are peptides and proteins, stimulate growth of various tissues

Prostaglandins – modified fatty acids, often derived from lipids of cell membrane,

7. Where could a hormone receptor be located?On cell membrane, in cytoplasm or in nucleus

8. A protein hormone and many peptide hormones would bind with a receptor located in this place. On cell membrane

9. Steroid hormones, thyroid hormones, and some local regulators would bind to receptors located in these places. In cytoplasm or in nucleus

10. Name 9 endocrine glands in a human body. Hypothalamus, pituitary gland, thyroid gland, parathyroid glands, pancreas, adrenal glands, gonads, pineal gland, thymus

11. What is the anatomical relationship between the hypothalamus and the anterior pituitary?(see Figure 45.7 and text on page 900) Be detailed about the connections between the two structures.

See figure and text for description

12. What is the anatomical relationship between the hypothalamus and the posterior pituitary? (see Figure 45.6 and text on page 963) Be detailed about the connections between the two structures.

See figure and text for description

13. What hormones are released by the hypothalamus to control the anterior pituitary gland. What is the chemical composition of these hormones and what is the action of each hormone? Releasing Hormones and Inhibiting Hormones, peptide in composition, to stimulate or inhibit the production and release of anterior pituitary gland

14. Where does the posterior pituitary come from during embryological development?From the brain

15. Where does the anterior pituitary come from during embryological development?From the roof of the mouth

16. What hormones are released from the posterior pituitary, where are they produced, what is their chemical composition, and what is the target organ and action for each hormone. See Table 45.1 Oxytocin and Antidiuretic Hormone, hypothalamus, peptide, target organ for Oxytocin is the uterine smooth muscle and mammary gland cells

17. What hormones are released from the anterior pituitary, where are they produced, what is their chemical composition, and what is the target organ and action for each hormone. See Table 45.1 Growth Hormone, Prolactin, Follicle Stimulating Hormone, Luteinizing Hormone, Thyroid-stimulating Hormone, ACTH, MSH, Endophins; anterior pituitary, peptide,

18. What single molecule from the anterior pituitary is cleaved into a number of smaller hormones and what are these hormones? Pro-opiomelanocortin – ACTH, MSH, and endorphins

19. What hormones are secreted by the Thyroid gland, what is the chemical composition of the hormones, and what do these hormones do in humans or other vertebrates? What element do these hormones contain (this element is found nowhere else in the body)? See Table 45.1 and pages 965-966. Triiodothyronine (T3) and Thyroxine (T4), modified amino acid, metamorphosis of the frog, metabolism in humans/mammals

19. Explain the concept of a Negative Feedback Control Loop using the Thyroid Hormone system. Use Figure 45.8 for your answer.

See Figure and text for example

20. What hormone is secreted by the Parathyroid Gland, what is the chemical composition of this hormone and what does this hormone do in the body?

Parathyroid Hormone!! Peptide, elevates blood Ca levels by stimulating Ca reabsorption from bone and kidneys

21. What hormone is secreted by alpha cells and what hormone is secreted by beta cells in the Pancreas, what is the chemical composition of these hormones, and what do these hormones do in the body? See page 966 and Figure 45.9 alpha cells = glucagon while beta cells = insulin, protein, insulin decreases blood glucose levels while glucagon increases blood glucose levels

22. What cells are stimulated by insulin and what cells are not stimulated by insulin? And stimulated to do what? Stimulated = all cells except neurons, to take up glucose from the blood. Neurons are always able to do this, even without insulin

23. What is meant by Type I and Type II diabetes (juvenile versus adult onset diabetes) and what is the cause of each type? See page 968 and Figure 45.10

Type I – Juvenile Onset, destruction of beta cells so no insulin is produced or secreted Type II – Adult Onset, fewer receptors on cell membrane so insulin has less of an effect.

24. What are the two parts of the Adrenal Gland, what hormones are secreted by each part, and what do these hormones do in the body?

Cortex – responds to endocrine signals by ACTH by secreting glucocorticoids such as cortisol and mineralocorticoids such as aldosterone which both have effects on glucose metabolism and bioenergetics.

Medulla – responds to nervous signals from autonomic nervous system, causing release of epinephrine and norepinephrine

25. What is the chemical composition of the adrenal medulla hormones? Modified amino acid hormones

26. The adrenal medulla has close developmental and functional ties with the Nervous System.

27. How is the adrenal gland involved in the stress response? See Figure 45.14

28. Give some examples of hormones found in invertebrate animals and give the function for these hormones.

See pages 956 and 957

29. Where is the pineal gland? What hormone does it produce? What is the chemical composition of the hormone, when is the hormone secreted, and what does the hormone do?

(page 902-903) in the brain, Melatonin, modified amino acid, during the dark part of 24-hr cycle, regulates reproductive cycles, biological clock, pigment cells in certain vertebrates

30. Endorphins are called the body’s natural Opiates, because they inhibit the perception of Pain. (page 902) The receptors for endorphins are also receptors for these exogenous compounds or drugs: Heroin and other opiate drugs