For body cells to function properly, the following conditions need to be balanced:
1. BLOOD SUGAR
2. BODY WATER
3. BODY TEMPERATURE.
These three factors have to be in the right proportion for the cells and the body as a whole to function properly and to maintain homeostasis.
Blood sugar is the source of energy in the cell and it is required by all cell for carrying out the normal biochemical reactions in the body. The biochemical reactions in the body use water as a medium of reaction, thus the water balance in the body must be maintained. The body temperature also need to be kept at the normal level or else the normal biochemical reaction of the body will not be able to take place, due to the fact that incorrect temperatures deactivate the enzymes that mediate biochemical reactions.
A suspension is a heterogeneous mixture in which solute-like particles settle out of a solvent-like phase sometime after their introduction.
The neuron releases chemical messengers. Otherwise, there would be no 'signal transduction' in the postsynaptic cell. So, your answer is B.
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<h3>⇝ <u>Epidermis</u> :</h3>
Protective tissues includes epidermis & cork. Epidermis is basically a simple permanent tissue, protective in function. It forms one-cell-thick covering over all the parts of plant.
<h3>⇝ <u>Characteristics of Epidermis</u> : </h3>
- Epidermis is formed of living cells, arranged in a single layer.
- In aerial parts, epidermis is covered with a waterproof and noncellular waxy covering called cuticle.
- Cells form a continuous layer, but in leaves epidermis has small openings called stomata.
- Each stoma is guarded by a pair of bean-shaped guard cells which govern opening & closing of stomatal aperture.
<h3>⇝ <u>Functions of Epidermis</u> :</h3>
- Epidermis protects the underlying tissues from mechanical injury, chemicals & infection.
- Cuticle of epidermis protects against water loss & desiccation. It checks the rate of transpiration & evaporation and prevents wilting.
- Stomata in the epidermis of leaves help in gaseous exchange during respiration & photosynthesis.
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