The Thyroid

Discussion Assignment:

1. Thyroid hormones exert their effects on cells in a manner similar to steroid hormones; describe the mechanism of action of thyroid hormones.
2. Why would an imbalance in thyroid hormones have such widespread effects on the body?
3. Why was goiter observed in George’s case?
4. Why would calcium homeostasis be impaired in response to removal of the thyroid gland?
5. What could be used to specifically destroy the thyroid gland and have minimal effects on other cells and tissues in the body?

Case Study:

George is a thirty five year old hardware clerk. During his routine physical he casually mentions to his physician that he seems to be sweating more profusely than normal and most rooms that once were comfortable are now too "hot". At home a room that his wife and children find to be comfortable causes him to sweat profusely. George also reports that he seems to be losing weight even though his appetite has increased. He also complains that he has a shortened attention span and that he always wants to be moving around. Despite the fact that he feels fatigued, George claims to have difficulty sleeping and seems to have more frequent bowel movements, occasionally accompanied by diarrhea. The physician discovers George has lost 15 pounds since his last physical. In checking his chart, the physician finds that George has a negative history for chronic illnesses, does not smoke, and has a low risk for cardiovascular disease. He does however have a positive family history for autoimmune diseases. His father suffers from idiopathic thrombocytopenia, his mother has been diagnosed with rheumatoid arthritis and his oldest sister was recently diagnosed with systemic lupus erythematosus.

Results of George's physical examination were within normal ranges with the exception of the following: he demonstrated tachycardia, loud heart sounds, and apparent cardiac arrhythmias accompanied by slight hypertension. These arrhythmias were confirmed by electrocardiogram to be supraventricular in origin. George's eyeballs appeared large and protruding and his hair was fine and soft. He was also beginning to demonstrate some degree of alopecia. George was also observed to have palmar erythema. palpation of the neck revealed the presence of goiter. Results of blood tests indicated elevated concentrations of thyroid hormones (thyroxin and triiodothyronine), hypercalcemia, and decreased circulating concentrations of lipids. Based on the physical characteristics and the results of the blood tests, George's physician suspected that George was suffering from some form of hyperthyroidism and sent him to an endocrinologist to confirm the initial diagnosis.

Following the initial consultation and examination, the endocrinologist ordered tests to determine whether George was indeed hyperthyroid. The test results indicated an elevation in the concentration of thyroid hormones in the blood and the presence of thyroid-stimulating antibodies. These antibodies specifically stimulate the thyroid gland by binding with the thyroid stimulating hormone receptor located on the plasma membrane of the follicular cells of the thyroid gland. Based on these results, the endocrinologist concluded that George had Grave's disease, a form of hyperthyroidism believed to be autoimmune in nature. George was presented with a number of possible treatment options. These included treatment with chemicals (propylthiouracil and methimazole) that decrease the production of thyroid hormones by the thyroid gland, radioisotopic destruction of the thyroid gland by the use of ¹³¹I, and surgical removal of the thyroid gland. After considering all the options, especially the possible effects of radiation on gamete development, George chose surgery. Following successful surgery, George was prescribed synthetic thyroid hormone to ensure that his body was receiving adequate thyroid hormone and told to return within 2 months for a follow-up evaluation of circulating thyroid hormone concentrations. He was also cautioned to carefully monitor his calcium intake.

Subject Pathophysiology

What are four major functions of membrane proteins? How are membrane proteins inserted into the membrane - give details of two methods. Give a specific example of a protein that is an integral membrane protein. How can we determine from gene sequence information whether the protein will be an integral membrane protein?

Kidneys filter the blood and remove waste and extra fluid from the body and are essential for maintaining good health.

• What is one possible reason for kidney failure? Why would someone die if kidney failure occurs?
• Humans have two kidneys, but they can survive with one. Given the crucial function of the kidney, would you ever consider donating one of your kidneys to someone else? What factors would go into your decision?
• Hypothetically, what impact would having only one kidney have on a person’s health?

type in your own words

Questions to answer:

1. Do you think a potential new partner has the right to know if you had an STD?
2. At what time in a relationship do you share with a partner that you have an STD?
3. Would you mandate a new partner have an STD test before you get involved?
4. In your opinion, which 2 STDs would be the easiest to contract and why?

For your original post, you will need to create a thorough and thoughtful response to the discussion prompt. In your post, you must include information from at least two references A good post will clearly address the prompt and will include precise examples from the reading or source.  You also must end your post with a question/questions for the reader/students to respond to. 250 word requirement.

Describe a protocol for isolating mitochondria from rat liver and for estimating the purity of the preparation.

You obtain three samples from three different populations.

Observed genotype frequencies.

Population 1 AA=0.70 ; Aa=0.25 ; aa = 0.05

Population 2 AA=0.35 ; Aa=0.55 ; aa=0.10

Population 3 AA=0.45 ; Aa=0.40 ; aa=0.15

Populations 2 and 3 have no barrier between them. But populations 1 and 2, and populations 1 and 3 have a barrier between them.

What are the FST values between these three pairs of populations?

1: How are endocrine disruptors associated with IQ?

2: Why has research on endocrine disruption spurred so

much debate? What steps do you think could be taken

to help establish greater consensus among scientists,

industry, regulators, policymakers, and the public?

3: THINK IT THROUGH You are the parent of two young

children, and you want to minimize the environmental

health risks your kids are exposed to. Name five steps

that you could take in your household and in your daily

life that would minimize your children’s exposure to environmental

health hazards.

describe the structure and replication of DNA and how it allows genetic information to be passed on from generation to generation.

Organism 3

Field Notes: Specimen collected from shaded area along stream in South Cumberland State Park (Grundy County, TN)
Laboratory Analysis:
Body: Large leaves emerging from underground rhizome
Size: 63cm

Chromosomal Analysis: Plant body is diploid --chromosomes number of 44

Lignin test: Positive

Cuticle: Present

Leaves: Present -- large with branched veins. Underside has sori(containing haploid spores)
Roots: Present-----branch from the inside
Stem:Present--- vascular tissue(xylem and phloem)present



Life History: Diploid sporophyte dominant generation. Haploid spores germinate into heart-shaped, haploid, gametophyte. Water required for fertilization due to flagellated sperm; no seed is produced. Diploid zygote develops into sporophyte of life ---each bearing ether megasporangia or microsporangia but not both. Insects, especially beetles, appear important in pollination   

Question: Explain which domain, kingdom and phylum you believe this plant should be classified in.

Communication: The local media features the work of your team on their nightly news. During a live interview the reporter asks you " Apparently this plant requires water for fertilization, can you explain, can you explain why"?

Response: ------------------------

Application of the A&P of the Animal & Plant Cell: Relate the structures of the cell (animal or plant) to parts of some other concrete or abstract structure and explain how each structure connects.
Example: Gas to a car is to the mitochondria of the cell. Explanation: Without gas a car would have no means of energy for power to move. Just as the mitochondria "powerhouse" provides energy for the cell.
* Whatever structure chosen to compare the cell to that structure must be used throughout the entire comparison. . * There should be approximately thirteen (13) comparisons. One for each part of the cell. Please number each part in your comparison.

1. Which of the following is essential for male sexual behavior in both rats and monkeys?

a. The vomeronasal organ

b. The main olfactory bulbs

c. The amygdala

d. The medial preoptic area

e. All of the above

2. In a sex test with a male and female rhesus monkey, which of the following would be the best measure of the female’s attractivity?

-The male mounting the female

- T estosterone concentrations in the male’s blood

-The female approaching the male

- The female performing lordosis

- Estrogen concentrations in the female’s blood

1. The E. coli LacZ will be used as a reporter gene and the expression of the LacZ gene product will be detected by the enzymatic cleavage of the compound X-gal producing blue staining within the embryo. Why was an E. coli LacZ gene used as a reporter gene?

2. Why is there a Drosophila weak basal promoter located on the P[lacZ] enhancer-trap element?

3. The E. coli LacZ will be used as a reporter gene and the expression of the LacZ gene product will be detected by the enzymatic cleavage of the compound X-gal producing blue staining within the embryo. If blue staining is observed, what does that indicate about the P[lacZ] enhancer-trap element within the Drosophila embryo?
4. What classes of genes will be studied in this experiment?
5. When you examine your prepared slides you observe that some embryos do not show a staining pattern, give a technical reason for this observation. Give a biological reason for this observation.

1 The Krebs Cycle occurs in/on the

A matrix of the mitochondria.

B cristae (inner membrane) of the mitochondria.

C stroma of the chloroplast.

D cytoplasm of the cell.

E thylakoid membranes of the chloroplast.

At the end of glycolysis,

A a net of 2 ATP have been produced.

B one NADH has been produced.

C oxygen is released.

D two FADH2 have been produced.

E one glucose has been produced.

The majority of ATP produced by aerobic respiration is made in

A glycolysis.

B the Krebs Cycle.

C the electron transport chain.

D fermentation.

Glycolysis occurs in/on the

A matrix of the mitochondria.

B cristae (inner membrane) of the mitochondria.

C stroma of the chloroplast.

D cytoplasm of the cell.

E thylakoid membranes of the chloroplast.

_______________________ are stripped from the intermediate organic molecules of the Krebs Cycle.

A carbon and hydrogen atoms

B oxygen and electrons

C H+ and electrons

D ATP and NAD