The correct answer to the question above is cytoskeleton. Microtubules, microfilaments, and intermediate filaments make up the cytoskeleton, which lies beneath the plasma membrane and provides support, movement, and shape for the cell. These structures definitely form cytoskeleton for the support and structure.
Answer:
Electron microscope would be used for if,
C) details of cell structures needed to be distinguished.
Explanation:
- The general principal of electron microscopy is analogous to light microscopy except that it uses electrons to analyse the specimen instead of light.
- Electron microscopy focuses a beam of electron on the target sample and records the difference in absorption by different surfaces.
- Electron microscopy is used to get the detailed structure of cells and surface features of various viruses and bacteria.
- However, it is not possible to view living biological samples through electron microscope because high velocity electron have immense energy to kill living cells.
- These samples are thus, fixed and then viewed.
Answer:
The correct answer is D. The surface of the skin can be mapped into distinct regions, each served by a single spinal nerve: these regions are called dermatomes.
Explanation:
A dermatome is the area of skin innervated by a single spinal nerve and its spinal ganglion. The cutaneous nerves are those that reach the skin, picking up the sensitivity of the skin. Each cutaneous nerve is distributed in a certain area of skin, called a dermatome.
A pair of posterior or sensory roots and a pair of anterior or motor roots arise from each cord segment, joining laterally at the level of the intervertebral foramen to form a mixed spinal nerve. Each of these innervates a strip of skin called a dermatome, so the body surface can be considered a true mosaic of these.
In the extremities the arrangement of dermatomes is more complicated because of the embryological rotation of the limbs as they grow from the trunk.