Answer:
A silicon atom has 14 electrons around the nucleus, and of these, there are 4 valence electrons on the outermost orbital. When this is made into a single crystal, it can be used as a material for semiconductor products. When it crystalizes, the nuclei share electrons and they bond with 8 electrons around each nucleus.
A solar eclipse occurs when the moon gets between Earth and the sun
Answer:
A model can represent something very large like the solar system, A model can represent something very small like a single cell, A model can represent something that cannot be seen or touched, A model can represent something very complex like the flow of energy in an ecosystem.
Explanation:
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Answer:</h3>
B) partial pressure of oxygen
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Explanation:</h3>
- All tissues and cells in the body require oxygen to carry our respiration for the provision of energy in the form of ATP.
- Oxygen is exchanged in the lungs and is loaded into hemoglobin, a pigment in the red blood cells that carries oxygen in the tissues. This occurs through simple diffusion that is facilitated by a concentration gradient.
- In the tissues, internal respiration takes place where oxygen is unloaded from hemoglobin and diffuses into nearby cells. Diffusion occurs as a result of the difference in the partial pressure of oxygen in the blood vessels and that in the blood tissues.
- The partial pressure of oxygen in the blood vessels is higher compared to partial pressure in the cells, thus, the oxygen gas will diffuse into the cells.
Radiation - The other two ways are conduction and convection, both of which need matter to transfer energy.