Application Question 8 - Skin Problem

 
Application Question 8

    Due Feb 18 by 11:59pm Points 10 Submitting a file upload Available until Mar 26 at 1pm

This assignment was locked Mar 26 at 1pm.

Before we move on to some new topics about the skin, let's take a moment to reflect on our discussions in our last class meeting.  Feel free to look back at your notes or the Zoom recording of the last meeting to refresh your memory!

Some sort of disease, injury, or infection has afflicted someone’s skin! Your job is to figure out what’s going on and show your evidence for conclusion.

Clues
Keratinocyte: Desmosomes disrupted. Sending cytokines to attract WBCs. Keratinocyte Stem Cell: Dividing more rapidly to replace cells. Making complement proteins to seek out microbes. Melanocyte: Momentarily detected increased UV radiation in the skin but then the stimulus went away. Langerhans Cell: Identified numerous targets and am eliminating them. Fibroblast: There’s a need for a small amount of new dermal protein fibers. Dermal Dendritic Cell: No unusual activity requiring my services. Merkel Cell: Sensed a sudden increase in pressure in one area of the skin. Lamellated Corpuscle: No signals out of the ordinary.

Using a spare piece of paper or an index card or post it, create a diagram of the skin based on the clues. All 8 cell types and information from the clues should be represented. Show or label your idea of what the skin problem is!

Take a picture of your diagram and upload it here.

Don't spend too much time on the artistry!  Remember that we started this together during Zoom and I showed some ways to do this with simple lines and abbreviations!

Note: This is intended to be done on paper, not on a computer. If you're using the Canvas phone/table app, you can take a picture of your diagram with your device and upload it directly from there within the Canvas app.  If you're not using the app, you can send the picture to yourself by email and then upload it here on your computer.

Mostly Complete (10 pts): Diagram shows all 8 cell types in their appropriate positions/layers.  To clarify the locations of cells, check the location information in the clues in this sorting activity
Links to an external site..  You might compare those location descriptions to a diagram of the skin's layers, such as this one

Links to an external site..  Diagram shows or mentions a reasonable injury, disease, or infection based on the evidence in the clues.

Partially Complete (6 pts): One or more of the 8 cell types is not shown or appears in the wrong location in diagram.  Or information on a skin problem related to clues is absent.

Application Question 7-Abestos

 

Application Question 7

• Due Feb 11 by 11:59pm
• Points 10
• Submitting a text entry box
• Available until Mar 26 at 1pm

This assignment was locked Mar 26 at 1pm.

Now that you have had an opportunity to reflect on this question and get some ideas from colleagues, take this opportunity to more formally record a response...

Pretend you’re called as an expert witness in a court case about asbestos. The person suing (the plaintiff) worked in an asbestos mine in Canada and says it is now hard for him to breathe due to exposure to asbestos. As an expert witness, use your A&P knowledge to describe to the judge how the asbestos could relate to the plaintiff's difficulties.  You should...

Describe two different membranes that you think are likely impacted, including where those membranes are located, what specific tissue types they're are made of, and how you think the presence of spiky asbestos within those membranes could inhibit their normal functions.

You might want to open another window to go to earlier pages in this module and remind yourself of where asbestos can go to in the body.

Mostly Complete (10 pts): Describe mucous membranes and serous membranes in terms of their locations and cell/tissue composition.  Please be specific regarding tissue types (e.g., what type of epithelial or what type of connective tissue)!  Make a prediction (at least a guess!) at how the functions of those membranes might be impeded if stiff, spiky asbestos was embedded within them.

Partially Complete (6 pts): Mucous and serous membranes identified, but one of above details missing.

 

                 When asbestos fibers are inhaled, they can reach the alveoli, a tiny air sac of the lungs. Asbestos fibers are not only penetrate the pleura but also reach the alveoli. The pleura consists of a serous membrane, composed of a layer of simple squamous cells called mesothelium which is supported by connective tissue. The pleura located double-layered membrane in the thoracic cavity covers the lungs called parietal pleura and visceral pleura consist of a serous membrane.The pleura acts as protective barrier, reducing friction during lung movement and facilitating efficient breathing.  

                When inhale asbestos fibers, that spiky asbestos fibers embedded within mucous membranes and serous membranes. Asbestos fibers stuck on the alveoli  cause chronic inflammation and damage to the alveolar cells and endothelial cells.Asbestos fibers can lead to fibrosis and scarring of the epithelial lining.Fibrosis develops within  squamous epithelial cells that form the alveolar walls .Asbestos fibers on cells affect blood flow within the alveolar  membrane. Chronic inflammation leading to thickening of the pleura that caused reduce the pleura’s elasticity and impair lung expansion follow by impaired gas diffusion, reducing the efficiency of oxygen uptake and carbon dioxide removal so that the patient presenting with breathing difficultly progressive shortness of breath.

Application Question 6- Acne

 
Application Question 6

    Due Feb 11 by 11:59pm Points 10 Submitting a text entry box Available until Mar 26 at 1pm

This assignment was locked Mar 26 at 1pm.

Now that you have had an opportunity to reflect on this question and get some ideas from colleagues, take this opportunity to more formally record a response.

acnePretend a friend tells you, “I can’t believe I still get pimples even though I’m not a kid anymore! My doctor keeps telling me not to poke or scratch at my pimples, but I always want to just get them off!”

Use an A&P perspective to explain why your friend’s doctor would say to not poke or scratch pimples. Use the words “myofibroblasts,”  “collagen,” and "migrate" in your answer.

Feel free to refer to the journal article excerpt

Download journal article excerpt about "wound healing vs. fibrosis," the last segment of the Zoom recording from class.

Mostly Complete (10 pts): Include myofibroblasts, collagen, and migrate in your response. In particular discuss the special characteristics of myofibroblasts and how this situation could lead to excess collagen production and that would form a scar.  Refer to the article linked above and especially some of the info at the end about how/why fibrosis occurs. There are some specific roles for collagen, especially, that might occur if this person is constantly irritating the skin.

Partially Complete (6 pts): Discuss relevant information related to the three key terms, but answer does not connect excess collagen production to the scenario/fibrosis.

         When you scratch a wound, it disrupts the delicate balance of skin cells and collagen fibers involved in the repair process. While wound healing is essential, chronic inflammation and excessive repair can trigger the accumulation of extracellular matrix (ECM). Myofibroblasts, responding to chemical signals, migrate to the wounded area and produce collagen and other extracellular matrix proteins. Although myofibroblasts play a role in wound contraction, their persistent presence can lead to excessive scar tissue formation, known as fibrosis. This occurs when the synthesis of new collagen by myofibroblasts exceeds the rate at which it is degraded, resulting in an overall increase in collagen content over time.Continuously scratching the healing process disrupts the formation of smooth collagen, leading to irregular scar tissue and permanent scarring. Therefore, doctors advise against poking or scratching pimples, as it not only worsens inflammation but also contributes to fibrosis or scarring.

Application Question 5-identical twin

 
Application Question 5

    Due Feb 4 by 11:59pm Points 10 Submitting a text entry box Available until Mar 26 at 1pm

This assignment was locked Mar 26 at 1pm.

Now that you've gotten to check your ideas by seeing some of your classmates' responses, let's take an opportunity to record your final thoughts for now.  Your response might be the same or different from in the previous discussion, but please re-write (or paste in) your complete answer.

Screen Shot 2018-10-04 at 11.49.08 AM.png

You run into your old friend, Aaron, who tells you that (strange as it sounds) he and his identical twin brother Jared got married to identical twin sisters! He says it’s going to be really exciting, because both couples just had baby girls, so his and Jared’s kids will also be identical twins!

Using your understanding of meiosis (e.g., including crossing over/recombination & independent assortment), what do you say to Aaron in response?

(Hint: since the important processes here act on pairs of chromosomes, it can be helpful to use "within pairs" or "between pairs" or "from each pair" frequently in your responses!)

 

Mostly Complete (10 pts): Describe issues related to both independent assortment and crossing over/recombination.  Both of those processes mean it's extremely unlikely Aaron and Jared will produce identical sperm, much less that those sperm will fertilize identical eggs from their partners.  Make sure response is clear that those processes occur between each pair of chromosomes (not between chromosomes from different pairs) in each individual's body.  The Week 5 lecture recording includes a discussion/clarification of this!

Partially Complete (6 pts): Explain just one of the two concepts described above.  Also note that responses will be marked only partially complete if they indicate that crossing over happens between mother/father or male/female or egg/sperm chromosomes.  Crossing over happens before fertilization within a single individual's body between that person's chromosome pairs.  Crossing over is not expected to happen between egg and sperm chromosomes after fertilization.

           Jared  and Aaron 's DNA that is passed along to their baby will include new combinations of codes due to crossing over. Crossing creates the new combinations of genetic material on chromosomes that is not possible  for these twins to create identical twin babies.  Cross over,  created their reproductive cells are made in independent assortment, there are numerous different combinations using the equation of 2 to the power of how many pairs of chromosomes they have (23), which makes more than around 8 million combinations.

        Meiosis is a division that a single cell divides twice and produces four daughter cells which  contain half the amount of genetic material from parents called sex cells (gametes).Meiosis produces cells that are genetically unique from the parents and contain only half DNA from parents.  Although the baby can inherit some traits from the parents their baby can not become identity twins liked Jared  and Aaron.


 

Application Question 4 - Disscussion about Cancer

 
Application Question 4

    Due Jan 28 by 11:59pm Points 10 Submitting a text entry box Available until Mar 26 at 1pm

This assignment was locked Mar 26 at 1pm.

Now that you've had a chance to clarify your ideas by reviewing some of your colleagues' responses, take a moment to share some of your final thoughts on the prompt below.

Prompt:

DNA Your friend tells you she recently had genetic testing done, and her doctor said she “inherited a single mutation in a gene that is connected to breast cancer.”

Your friend is unsure what this means and is worried she will definitely get breast cancer later in life.

We’ve now discussed many reasons why your friend would not be 100% guaranteed to get cancer - particularly aggressive cancer - based on just 1 mutation!

Explain at least three specific, cell biology reasons why.

Mostly Complete (10 pts): 

• Discuss the roles of at least three of the following in cancer development: 
• Cyclins
• Oncogenes, 
• Tumor Suppressors,
•  Metastasis, 
• Angiogenesis, 
• Desmosomes/
• Adherens Junctions, 
• Cell Specialization, etc.

Partially Complete (6 pts): Discuss only one or two of the factors above, or discuss three things but with incomplete or incorrect descriptions of their roles.

 

Based on just one genetic mutation my friend may not get cancer.Oncogene is a mutated gene that has the potential to cause cancer. The normal healthy adult their genetic and cellular mechanisms can prevent the growth and spread of the cancer mutation.

Cyclins control the progression of the cell cycle by activating particular enzymes one kinase in humans activates the proteins that carry out DNA replication.In healthy adult the DNA damage everyday which called mismatch ,but  DNA fixed by itself.The error form different form sometime nucleotide match the correct way. Each nucleotide contain base each DNA during replication the enzyme DNA polymerase help to bring the right partner pair with every base. The enzyme catches the mismatch and repair it right away which called mismatch repair.

 The healthy adult body the DNA mismatch repair by it self. Sometime lots of different molecules could cause chemical changes to nucleotide which was the trigger such as exposure from our environment chemicals , substances , UV light, contain chemical compound in smokes that caused DNA damage.  But our body have specific enzyme to reverse or correct the damage. Our body cell also has more general repair pathways . Just one base is damaged it can usually fixed by a process called base excision repair.  

If  double strand DNA is not damage she may not get cancer.   Cancer needs a blood supply to grow or spread  is called angiogenesis. Metastasis is spreading the cancer to other part of the body.

Application Question 3 -Imatinib drug

 This assignment was locked Mar 26 at 1pm.

Now that you've had a chance to think about this and refine your ideas by seeing some colleagues' responses, let's take a chance to record your final (for now) thoughts on this prompt.  I highly encourage you to review your colleagues' responses to in the past discussion before submitting your answer here!

• Imatinib is a drug that is used to treat leukemia.
•   It dissolves easily in water and has been found to build to very high concentrations in diseased cells.

Recall that we discussed four ways materials move across membranes:

1) simple diffusion
2) facilitated diffusion
3) active transport
4) endo/exocytosis.

Refer to this yes/no decision tree

Download yes/no decision tree for determining modes of transportation for chemicals.

Given the information above, you should be able to eliminate some of those 4 methods as possibilities for imatinib.

Which of the four transport methods can you eliminate in this case and how do you know imatinib is not using those transport methods to get through cell membranes?

In case it helps, the slides for this topic can be found here and there's also a video

Links to an external site. about membrane transport.

Mostly Complete (10 pts): Note that because this chemical moves to higher concentrations (goes against concentration gradient) that means it cannot be moving by any form of diffusion.  So we can eliminate BOTH of our forms of diffusion.  The drug is hydrophilic, so that's yet another reason it cannot move by simple diffusion, which is reserved for hydrophobic chemicals.

Click here to see information on revising application questions for additional points

Imatinib drug is easy to dissolved in water , so that it cannot be simple diffusion .  It is not facilitate diffusion because  Imatinib drug build up highly concentration. The molecule is large it cannot across lipid bilayer so that it  need assistant to eliminate  by endo/exocytosis.

 

Application Question 2- Body temperature homeostasis

              When the person was infected  corona virus the patient having the symptom of high temperature. During a fever, the body is maintaining a temperature of 101°F, it is actually operating within a negative feedback loop.The hypothalamus, a part of the brain, acts as the body’s thermostat and detects the elevated temperature. Chemical signals are released to the brain, alerting it to the increased temperature.In response, the hypothalamus triggers various physiological mechanisms to reduce the body temperature and restore it to the normal range.These efforts include sweating and vasodilation (expansion of blood vessels), which aim to bring the temperature back to normal. The normal body temperature typically hovers around 98.6°F (37.0°C). During a fever, a new set point temporarily shifts upward (from 98.6°F to 101°F) due to infection.The negative feedback loop then works to bring the elevated temperature back toward this new set point. Maintaining a temperature of 101°F during a fever example of rheostasis, where the body adjusts its set point to respond to specific conditions.The negative feedback loop ensures that deviations from this adjusted set point are corrected, promoting overall health and stability.

 

Application Question 1- Homeostasis osteoporosis

    Our body maintains calcium by homeostasis. When we don’t consume enough calcium through our diet, the body compensates by adjusting calcium levels.A special gland parathyroid gland is the control center that  senses changes in blood calcium levels and responds accordingly. Low calcium (stimulus) triggers the (effector) parathyroid hormone release.Parathyroid hormone stimulates bone cells  to break down bone tissue this process is called resorption. As a result, calcium is released from the bones into the bloodstream.When blood calcium returns to normal, PTH secretion stopped.This is the example of Negative Feedback Loop.The system self-regulates to prevent extreme deviations from the set point.Ultimately, this helps prevent conditions of osteoporosis.