Cells that are metabolically active and use a lot of energy: include red blood cells. include white adipose (fat storage) cells. are found in the dermal layer, just under the skin. are densely packed with numerous mitochondria. generally are not found in the human body.

are densely packed with numerous mitochondria.

Explanation:

Mitochondria are considered as the energetic centers of the eukaryotic cells. These organelles (mitochondria) produce energy in the form of Adenosine Triphosphate (ATP) through the mechanism of cellular respiration, i.e., mitochondria are the organelles where aerobic phases of cellular respiration occur. In presence of oxygen, mitochondria convert chemical energy obtained from foods to ATP, which is the energy coin that cells use to carry out all their metabolic processes (e.g., reproduction, growth, development, etc). Thus, cells with high metabolic requirements need to have many mitochondria in order to produce more ATP.

the  frequency of a wave represents  the number of wavelengths that pass a specific point per second. the unit for  frequency  is hertz (hz).

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