Answer:
basale - spinosum - granulosum - lucidum - corneum.
Explanation:
The order of strata in the epidermis:
- Basale: it is the deepest stratum. It has one layer of cells called keratinocytes, which are stem cells for the epidermis.
- Spinosum: The keratinocytes in this layer have spiny shapes. They synthesize cytokeratin and lipids. In this layer, we can also find macrophages.
- Granulosum: The keratinocytes of the previous layer ascend and synthesize keratohyalin, which is in granules. The keratohyalin helps to join keratin filaments. Also, the cells release the lipids synthesized in the previous layer, and they form a barrier that stops dehydration.
- Lucidum: it is only on thick skin, like the one in the sole of the feet. The keratinocytes in this layer have expelled the nucleus and now are dead cells. The keratinocytes have a flat shape and form a thin layer.
- Corneum: it is the most superficial layer. It is made of dead keratinocytes filled with keratin in their cytoplasm. It is a thick layer that suffers desquamation when new dead cells filled with keratin ascend from the previous layer.
T cells. When HIV arrives in the lymph nodes – around 24 to 48 hours after exposure – they activate other immune cells, such as CD4 t-cells, HIV's primary target.
Answer:
receptor down-regulation
Explanation:
Downregulation is a control mechanism by which a cell decreases the amount of a cellular component, such as RNA or protein, in response to an external variable. In contrast, a reactive increase of a cellular component is called upregulation. An example of downregulation occurs when insulin binds to its receptor and the complex is endocyted in the cell in response to hormonal signaling.
Only about 2% of the energy of the sun is captured by plants for photosynthesis, the remain 98% are utilized for other purposes. Some of the energy are reflected back into space [about 30%], some are absorbed by land, the ocean and the atmosphere [about 68%] and the rest are transformed into heat.
Biotechnology is a broad area of biology, involving the use of living systems and organisms to develop or make products. Depending on the tools and applications, it often overlaps with related scientific fields.