Gradual changes in the frequency of diseases over long periods are known as SECULAR TIME TRENDS. For example, the rate of mortality in USA due to coronary heart diseases over a period of time. Onset of puberty in girls is also a secular time trend.
Secular time trend is also referred as Secular Variation and Secular Drift.
Answer:
Due to inability to survive in aerobic condition.
Explanation:
The strain dies when exposed to a normal laboratory atmosphere instead of nitrogen gas atmosphere because the mutation causes change in the capability of the strain to survive in the aerobic conditions. This mutation inactivate several enzymes which is also responsible for their capabilities of surviving under both anaerobic and aerobic environment so that's why the strain dies when exposed to normal atmosphere..
The epidermis is a barrier to ultraviolet rays, blocking much of the cancer-causing radiation from reaching the nuclei of cells called keratinocytes.
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What is keratinocytes?</h3>
- Skin cells, also known as epidermal keratinocytes, are highly specialized epithelial cells created for a very specific purpose: separating the organism from its environment.
- Keratinocytes, which make up the majority of the epidermis, have a variety of functions that are crucial for skin restoration.
- They carry out the re-epithelialization process, in which keratinocytes move, multiply, and differentiate in order to reestablish the epidermal barrier.
- The majority of the epidermis's cells, known as keratinocytes, begin in the basal layer, manufacture keratin, and help to create the epidermal water barrier by producing and secreting lipids.
- A kind of stratified epithelium known as keratinized stratified squamous epithelium has many layers of squamous cells, or keratinocytes, with the superficial layer of cells being keratinized.
- The skin's epidermis is made up of this kind of epithelium.
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