Endocrine & Lymphatic systems Lab Exam

adrenal cortex secretes, is stimulated by, target tissue

Aldosterone, Cortisol; ACTH; all tissues

hypothalamic hormones

CRH, GnRH, PIH, TRH, GHRH, SS, PRF

pituitary gland secretes, is stimulated by, target tissue

GH, PRL, TSH, ACTH, FSH, LH, ADH, MSH, Oxytocin;

anterior pituitary gland secretes, is stimulated by, target tissue

GH, PRL, TSH, ACTH, FSH, LH; hypothalamus;

Tumors of the parathyroid gland often result in secretion of excess parathyroid hormone. Considering the function of this hormone, predict the effects of such a tumor.

Hyperparathyroidism; overproduction of PTH that results in excessive calcium reabsorption from bone, decreasing bone density, leading to fractures

posterior pituitary gland secretes, is stimulated by, target tissue

Oxytocin, ADH; hypothalamus; kidneys, mammary gland

adrenal medulla secretes, is stimulated by, target tissue

adrenaline and norepinephrine; ACTH; all tissues

CASE 3: The Parched Professor Your last call is to the aid of Professor Purple. Three witnesses are present from whom to take statements. Witness statements: Mr. Olive: "I swear that I saw him drink a full glass of water every half an hour today. He kept saying how thirsty he was!" Mrs. Blanc: "He must be going to the . . . well, you know, the little boys' room, two or three times every hour!" Ms. Feather: "He's been saying lately that his mouth is dry and that he feels weak. Personally, I think he should be drinking some of my herbal teas!" Based upon the witnesses' statements, what are your initial thoughts? Does one hormone come to mind that could produce these effects? Explain your reasoning.

because of the weakness and thirst he's experiencing, it sounds like he has low pressure, which stimulates antidiuretic hormone production

How are the endocrine system and nervous system similar? How do they differ? (be specific)

both control homeostasis; endocrine system regulates long term ongoing metabolic control while nervous system performs short term crisis management

CASE 2: The Bloated Mrs. Blanc Your next call is to the home of Mrs. Blanc. As before, you have three witnesses to interview. Witness statements: Ms. Magenta: "Between you and me, she's really let her- self go. She has fat deposits in all of these strange places, like around her face and trunk, and a weird hump on her back. If you ask me, some exercise may do her some good!" Col. Lemon: "Not that I want to talk about such things, but she's seemed bloated, a bit swollen, lately. She told me that even her blood pressure has gone up!" Ms. Feather: "The poor dear. She's been sick so much lately with all kinds of infections. Personally, I think her immune system needs boosting. But my herbal teas don't seem to help." What are your initial thoughts, based upon the witnesses' statements? Does one hormone come to mind that could produce these effects? Explain your reasoning.

cortisol, since it increases sugars in the blood, which explains the fat deposits. these signs also may point to stress

Based upon the witness statements and the laboratory analysis, what is your final diagnosis? (Hint: Think of the hormone that is supposed to trigger water retention from the kidneys. Is there a disease where this hormone is deficient?)

diabetes insidipus is the underproduction of ADH and causes chronic dehydration because too little ADH is produced and secreted, not enough water is reabsorbed by the kidneys. Although patients feel thirsty, and increase their fluid consumption, this doesn't effectively decrease the solute concentration in their blood because ADH levels are not high enough to trigger water reabsorption in the kidneys.

You interview Professor Purple and collect blood and urine specimens to be sent off to the lab for analysis. The lab reports that the urine osmolality is 150 mOsm/kg, which means that the urine is overly dilute (too much water in the urine). The blood osmolality is 300 mOsm/kg, meaning that the blood is overly concentrated (too little water in the blood). The lab also reports that his blood glucose is completely normal. What is the significance of these clues?

his low blood pressure and ADH is increasing fluid retention and stimulating thirst in order to raise blood pressure

The hormone calcitonin is prescribed to treat the disease osteoporosis. Explain why this hormone would help to reduce bone loss in patients affected with this disease.

it's role is inhibiting the activity of osteoclasts and increasing osteoblast activity

You see the Colonel and collect some blood to send off to the lab. The analysis comes back as follows: T3 (triiodothyronine): 0.03ng/dl (normal: 0.2-0.5ng/dl) T4 (thyroxine): 1.1ug/dl (normal: 4-7ug/dl) TSH (thyroid-stimulating hormone): 86mU/l (normal: 0.3-4.0mU/l) Analyze the results. Why do you think the T3 and T4 are low and the TSH is elevated?

low blood levels of T3 and T4 stimulate the release of thyrotropin-releasing hormone (TRH) from the hypothalamus, which triggers secretion of TSH from the anterior pituitary; conclusion: lack of thyroid hormone production

pineal gland secretes, is stimulated by, target tissue

melatonin; darkness; various tissues

In the condition called DiGeorge syndrome, infants are born with either an absent thymus or a thymus that isn't functional. Predict the consequences of this disease.

no production of thymosin, a hormone needed for the production of T cells. Affects growth and development of children

parathyroid gland secretes, stimulated by, target tissue

parathyroid hormone; low calcium levels; kidneys, intestine

Your next step is to speak with Mrs. Blanc. During the interview you notice a bottle of pills on her nightstand. You log the pills as evidence and send them off to the lab for analysis. The lab report shows the pills to be the medication prednisone, which you know to be a glucocorticoid similar to the hormone cortisol. It turns out she has been taking prednisone for every day for the last two years for an autoimmune condition. Is this finding significant? Why or why not?

prednisone contains glucocorticoids which her body doesn't need because her body already has glucocorticoids (cortisol) ACTH is already releasing in her body, it results in too many corticoid hormones; conclusion: overproduction of cortisol hormone

Endocrine glands are often called "ductless glands" because their products are secreted directly into the bloodstream. How is this an example of structure following function?

secrete hormones directly into the surrounding fluid and into different parts of the body

thyroid gland secretes, is stimulated by, target tissue

t3, t4, calcitonin; pituitary gland; most tissues, bone

Drugs known as potassium-sparing diuretics work by blocking the effects of aldosterone on the kidney. What effect would these drugs have on the amount of urine produced? What effect would these drugs have on blood pressure? What effects would these drugs have on the potassium ions concentration in the blood?

the blocking aldosterone prevents the reabsorption of sodium, encouraging water loss, leading to low blood pressure high potassium levels, increased amount of urine

Explain why blockage or removal of the lymphatic vessels can result in significant edema (accumulation of fluid in a limb or body part).

the lymphatic vessels wouldn't be able to drain fluid from tissues throughout the body which can cause swelling because of the fluid

CASE 1: The Cold Colonel You are called upon to visit the ailing Col. Lemon. Before you see him, you speak with three witnesses who were with him when he fell ill. Witness statements: Ms. Magenta: "Colonel Lemon has been hot-blooded for as long as I've known him. But I noticed that he couldn't seem to keep warm. He kept complaining about being cold. . . ." Mr. Olive: "Just between you and me, I've noticed that the old chap has put on quite a bit of weight lately." Professor Purple: "The Colonel and I used to go on major expeditions together. Now he just doesn't seem to have the energy to do much of anything." What are your initial thoughts about the witnesses' statements? Does one hormone come to mind that may be the cause? Explain your reasoning.

thyroid hormone isn't functioning sufficiently

Predict some potential consequences of removing the spleen.

weakened immune system, unbalance of bodily fluid