Judy sat down, drank water from her bottle and wiped sweat from her face. She loves to sunbathe every summer. Judy decided that her usually pale skin had become quite tanned, in fact it turned out to be a little red.
Judy paused for a second to scratch her calf of the leg. For several days, the itch had been bothering her, and she decided that she had been bitten by mosquitoes the night before. She leaned over to take a closer look and was surprised to find that this was not a mosquito bite, but a mole. As long as she remembers herself, this mole was, but she had never itched before. She looked more closely and noticed that the "mole" looked a little different than she remembered. She was a little bigger and the edges were jagged. One edge was slightly darker than the other, and in the middle was a rising purple-black dot, which she tried to erase, but could not.
Judy shook her head: “In any case, I just noticed that the mole on the leg looks strange, and it itches, I should think.”
Mariah sat with a worried expression on her face: "Let me see this." When she looked at Judy’s leg, she said quietly: “Maybe you should go to the clinic”? While Judy looked at her, she continued: “My mother sent me a brochure about skin cancer last year. You know, trying to convince me to stop lying in the sun for a long time. I looked at it before throwing it in the bin. I remember some photos of skin cancer, and they looked like your mole. ”
"What are you talking about?" Judy exclaimed defensively. “How can I have skin cancer? I was not so long under the sun rays compared with you. "
"Good good. I'm not a doctor. I just remember these pictures. Well, let's just call the clinic so they can examine you. I’m sure they will tell you that I’m crazy. ”
Issues for discussion:
1. Judy has a change in her mole that occurred under the influence of the sun. What is the name of this process? Explain.
2. What is the reason for Judy's mole color change? What changes in the DNA molecule occurred under the influence of this factor?
3. What other factors can lead to the transformation of normal cells?
4. What type of tumor are moles? Explain the answer.
1) The change that have occurred in the mole is due to the sun light. The rays directed from the sun on the skin surface are Ultraviolet radiations. These radiations in a limited amount are not hazardous to the cells. But, sunburn which is an output of excessive exposure to these rays may trigger changes in the genetic structure of the cells such as the melanin producing melanocytes.The genetic content is present in the form of De-oxyribose nucleic acid and this in turn is altered and the process is referred to as DNA damage. This change can be reflected in the phenotype or the appearance of the cells.
2) First, the change that have been mentioned in the case is related to the melanocytes. These cells are the ones responsible for the phenotypic appearance of the skin. Let us consider a single mole cell being exposed to the UV rays. Due to this, DNA damage occurs and the altered cells proliferate in an unconstrained manner. The change happens in the structure of the DNA and this is referred to as mutation.
3) Now, from the above mentioned case, the gene encoding for the pigment will show change and there are chances that the mutated sequence will be transferred to the next generation. This is one factor responsible for the transformation process.Apart from this, there are certain mutagens like Ethidium Bromide which can result in the same output. Most of the factors associated with skin cancer should tend to have exposure to the skin surface.
4) Now, from the above mentioned case, the gene encoding for the pigment will show change and there are chances that the mutated sequence will be transferred to the next generation. This is one factor responsible for the transformation process. Apart from this, there are certain mutagens like Ethidium Bromide which can result in the same output. Most of the factors associated with skin cancer should tend to have exposure to the skin surface.