The structure of the skin is an effective barrier against bacteria. The multiple layers of epidermis, while can be invaded by foreign organisms, has a high turnover rate which means it is constantly shedding, therefore even the bacteria is shed protecting the body. Lastly, the skin's lipids maintain an acidic pH which slows and stops growth and replication of bacteria.
Answer:
Nerve cells release chemical signals into synapses between them (short distance). They also transverse their lengths with an electrical signal that can result in signal travel along a series of cells (long distance).
Explanation:
Nerve cells release neurotransmitters in the synaptic cleft which are capable of affecting nearby cells such as other nerve cells and muscle cells. Neurotransmitter molecules include, among others, serotonin, acetylcholine, dopamine, norepinephrine and histamine. Moreover, the synaptic cleft is the space that separates a neuron cell and its target cell. On the other hand, neurons transmit signals through electrical impulses. Electrical impulses travel long distances in the body carried by axons of the nerves. Thus, nerve impulses connect the brain and spinal cord and they carry signals to different parts of the body.
Answer:
Differences in their boiling points
Explanation:
When crude oil is distilled and separated into categories, the categories are characterized by the differences in their boiling points.
At different boiling points, each of the fraction will separate out.
- Crude oil is made up of different fractions of hydrocarbons.
- As the chain length of the hydrocarbon increases, the volatility reduces and boiling point increases.
- Components with short carbon lengths rises out from the column first and are cooled and extracted.
- The categories are thereby, classified based on differences in their boiling points.
