TSH- Thyroid-stimulating hormone

Here is the link to my podcast. https://docs.google.com/file/d/0B0n3ho2c-P5jakV1MldvbVVhVFE/edit

Transcript:

"Hello, my name is Blake Williams and in this podcast I will be teaching you about TSH, otherwise known as Thyroid-stimulating hormone. First of all, TSH is produced in the Anterior Pituitary Gland, and its function is that it stimulates the thyroid gland to produce thyroid hormones, such as T₃ and T₄. Those thyroid hormones are responsible for controlling the body’s metabolism. The production of T₃ and T₄ is controlled by a negative feedback loop based on the levels of these two thyroid hormones. When the levels are too low, for example, receptors on the plasma membrane of thyroid follicular cells send signals to the brain, specifically to the hypothalamus. The hypothalamus produces TRH, or Thyroid-releasing hormone, that travels to the Anterior Pituitary Gland and stimulates the production TSH. The TSH then binds to a TSH receptor on a thyroid cell, stimulating the production of T₃ and T₄. This system, in which the nervous system stimulates the endocrine system, is known as a neuroendocrine pathway.

It is good to take note that TSH production is regulated by the hypothalamus, and the TRH it releases. For example, if the concentrations of the thyroid hormones are too high, the hypothalamus will not send TRH to stimulate the production of TSH. Only once the concentrations of the thyroid hormone reach lower levels will the hypothalamus allow TSH to start producing again.

The last feature of TSH that I will talk about is that it is water-soluble. There is a big difference between water-soluble and fat-soluble hormones. Water-soluble hormones bind to receptors on the cell membranes, whereas lipid soluble hormones diffuse through the plasma membrane and bind with receptors on the inside of the cell. Also, fat-soluble hormones contain cholesterol, whereas water-soluble hormones do not."

References:



Benderson, Joshua B. "What is the function of thyroid-stimulating hormone (TSH) in the body?."    
          sharecare. 2014. http://www.sharecare.com/health/endocrine-system/what-function-tsh-in-body

"Thyroid Hormones (T3/T4)." Heal Yourself At Home. 2014.
          http://healyourselfathome.com/SUPPORTING_INFORMATION/CELL_
          MESSENGERS/HORMONES/AMINES/TH/t3_and_t4.aspx

"Thyroid stimulating-hormone." Wikipedia. 2014. http://en.wikipedia.org/wiki/Thyroid-
          stimulating_hormone

Cell Respiration Lab Report

TITLE: The Effect of Temperature on Cell Respiration in Yeast

ABSTRACT: In this lab, our goal was to find out whether or not temperature affects the rate of cell respiration. We used yeast as our organism, adding it, along with the glucose that it needs for cell respiration to occur, to four different vials. Each of these four vials had a syringe connected to it by a tube, allowing for us to see the volume of carbon dioxide produced by the cell respiration. After each of these vials were exposed to a different temperature, we found that the rate of cell respiration initially increased along with the increase in temperature, but as the temperature was increased past a certain point, or plateau, the rate of respiration then decreased.

INTRODUCTION: Cell respiration is a process that occurs in our cells, and involves converting glucose, which we get from the food we eat, into ATP energy. The chemical equation that represents cell respiration is C₆H₁₂O₆ + 6 O₂ à  6 H₂O + 6 CO₂ + 36-38 ATP. The Glucose is converted into ATP through 3 different processes, which are Glycolysis, the Krebs Cycle, and the Electron Transport System. Two products that are created through this reaction, other than ATP, are H2O and CO2. It is this produced CO2 that we will measure in our experiment to determine the rates of respiration. Since the volume of produced CO2 represents the rate of respiration, then temperatures affect on amount of CO2 produced directly represents its effect on the rate of respiration.

HYPOTHESIS: If equal amounts of yeast are added to a four different vials of water that each contain glucose, and are then exposed to four different temperatures, then the yeast exposed to a lower temperature than the control, which is the yeast at room temperature, will a lower rate of respiration than the control, and the yeast exposed to temperatures greater than the control will have higher rates of respiration than the control, because a decrease in temperature would result in less molecular motion, and less reaction, whereas an increase in temperature would result in an increase in molecular motion, and therefore an increase in rate of reaction, or rate of respiration.

MATERIALS:

1. 140 mL Water

2. 4.0 g Yeast

3. 4.0 g Glucose

4. 0.8 g Salt

5. Four Vials

6. Four Syringes

7. Four Connecting Tubes

8. Four Stoppers with Open Vent

9. Mass Scale

10. Heating Pad

11. Heater

12. Ice Bath

13. Graduated Cylinder

14. Beaker

15. Stop Watch

PROCEDURE:

1. Measure 35 mL of water and pour into four vials.

2. Measure and add 1.0 g glucose into each vial.

3. Measure and add 0.2 g salt to each vial.

4. Measure 1.0 g yeast for each vial.

5. Attach the four connecting tubes to the four syringes on one side, and to the stoppers with open vents on the other side. 

6. Push down the syringe to start at 1.0 mL. Then place the stoppers on each vial.

7. Put the vials into their temperature locations. One sits at room temperature, one is placed in an ice bath, one sits in a heater, and one sits in a beaker of water on a heating pad.

8. Pour the measured yeast into each vial, put the stoppers on, and start a timer.

9. Record the new mL shown on the syringes every 2 minutes. This represents the CO2 that is produced.

10. Make a data sheet and a graph.

RESULTS:

CO2 Produced + 1.0 mL
Minutes	Cold	RT	80*C	48*C
0	1.0 mL	1.0 mL	1.0 mL	1.0 mL
2	1.0 mL	1.0 mL	1.0 mL	1.0 mL
4	1.3 mL	1.2 mL	1.4 mL	1.0 mL
6	1.3 mL	1.1 mL	1.4 mL	0.8 mL
8	1.2 mL	1.7 mL	2.2 mL	2.6 mL
10	1.0 mL	2.0 mL	3.0 mL	5.0 mL
12	1.0 mL	2.2 mL	3.5 mL	8.0 mL
14	1.0 mL	2.3 mL	3.6 mL	10.0 mL

CONCLUSION: Our results from this experiment show that yeast held at temperatures below our control, which is room temperature, yield lower amounts of CO2 and therefore produce lower rates of cell respiration. On the other hand, yeast held at higher temperatures than the control yeast, once again the yeast at room temperature, yield larger amounts of CO2 and higher rates of cell respiration, but only up to a certain level. Since the yeast in the hottest temperature vial produced less CO2 than the yeast in the second hottest vial, this seems to suggest that their is a optimal temperature, and that after that temperature is exceeded, the rate of respiration will begin to decrease. Once the temperature passes the plateau, or temperature range that yields the highest possible rate of respiration, the enzymes that are used in the mitochondria are likely deformed and become no longer able to do their job. When one of these enzymes, for example ATP Synthase, become deformed, the substrates can no longer fit into the active sit and cannot be changed into products, such as ATP, water, and CO2. Our findings in this experiment somewhat reject my hypothesis. While I was correct in my prediction that lower temperatures than the control would yield lower rates of respiration, and higher temperatures than the control would produce higher rates of respiration, I did not predict that their would be high enough temperatures at which the enzymes would become deformed and cause a lower rate of respiration. Two constants in this experiment were the sugar that we added, glucose in all four, and the amount of the sugar added to each vial, which was 1.0 g for each. A potential sources of error for this experiment is that we don't think we added salt to one of the vials, and instead added double to one of them. Another potential source of error is that some CO2 may have escaped when one of the stoppers seemed loose.



CITATION:

Quick, Kevin, Holly Kiamanesh, Rosie Montague, Jennifer Blanchette, and Barbara

Akre. The Webb Schools Honors Biology Textbook. Claremont: CK-12

                Foundation, 2012. eBook.

Forensics Quiz

Leading Differential Diagnosis:

The bullet entered the left lateral side, went along the frontal plane, and then hit the inside part of his 8th rib, fracturing it. The bullet then fragmented and part of it ricocheted off the rib and came out 5 cm above the belly button. This is the most probable case because it is the least complicated path, and the shortest distance, for the bullet to go. It would have most likely gone through his heart, causing internal bleeding and death, since the heart is what controls the movement of your blood, so has a lot of blood coming through it. Below is a model of what I believe this path would look like.

Differential Diagnosis Model

Plausible Alternatives:

The bullet could have hit the second rib as it entered, and split into two pieces. One piece could of the bullet could have exited out 5cm above the belly button, while the other piece may have hit the eighth rib. This can be ruled out if the second rib was not damaged upon examination. This would mean that the bullet never hit this second rib.

The bullet could have hit the front of the vertebral body, fragmenting the bullet. With these fragments, the two injures would have been made. This could be ruled out by checking all of the vertebral bodies to see if they are normal or injured.

The bullet went down through his lateral left at a 45-degree angle and hit his right pelvic bone, and then bounced back up and exited 5cm above the belly button. After being shot, the victim fell down and fractured his rib, rolling onto his back before dying. If the pelvic bone is uninjured, then this can be ruled out.

Stem Cell Question!

If you were going to die, would you be okay with a clone being killed in order for you to receive the organ that will save your life?


If you were the president or ruler of your country, would you have clones made to fight in your country's military?


If scientists successfully become able to use Induced Pluripotent Stem Cells to cure diseases, rather than using Embryotic Stem Cells, will most people be okay with playing God?

Induced Pluripotent Stem Cells

     Induced Pluripotent Stem Cells (iPSCs) are stem cells that can be reprogrammed from adult cells, often skin cells. In most cases, skin cells are taken from an adult and reprogrammed using specific genes, four known ones being Oct4, Sox2, Klf4, and c-Myc. These genes, which are active only in embryos, are able to reprogram adult cells back into embyotic cells. At this state, the cell can become any of the 220 human body cells.

     Most of the testing done has been on mice. Scientist have been able to correct mutations, if they know where the mutation is located. They have been able to kill some diseases in mice that mimic human diseases.

     Scientist have been able to deliver these reprogramming genes through adenviruses, which only last for a short amount of time, but leave the genes permanently. Scientist have also been successful in tricking adult cells to reprogram using chemicals that mimic the reprogramming cells. Soon, scientist hope to make drugs that can reprogram instead of using viruses.

     At this point in time, there are too many risks, such growing a teratoma in the brain (a teratoma is a type of tumor formed from embryonic cells when something is injected under the skin), for scientist to experiment on humans. And there are many people who believe that playing the role of God is wrong, and who will never permit human testing.

The Island

     In our last class, we watched the first half of The Island. The movie deals with the morals of creating clones, and using the clones' organs as transplant organs for patients.

     In the movie, the clones are made for one purpose, and that is to supply organs for high paying patients. Once the desired organ is removed from the clone, they are killed (if not already killed from the process of removing the organ).

     The clones are forced to eat foods that better their health, as well as exercises often, in order to make sure that the organs are in best health. Additionally, they are stuck inside all day, and are told lies that keep them from questioning anything. They are also put to work, though it is unclear what there job is (they insert stuff into pipes or something like that).

     Is it fair to make clones for our own sake? That has been a question for many people. Very soon, people will have to make the choice whether it is ethical to make clones for our own profit, or to make an army of something like that.