Answer:
In humans, mature red blood cells are flexible and oval biconcave disks. They lack a cell nucleus and most organelles, to accommodate maximum space for hemoglobin; they can be viewed as sacks of hemoglobin, with a plasma membrane as the sack.
Explanation:
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A segment of DNA molecule found only in the body cells of organism
The sensory registers RECEIVED INFORMATION FROM THE EXTERNAL WORLD.
The sensory registers takes information from all the five sense organs and hold the information only for a few seconds, maximum of twenty seconds. Sensory register is the most intermediate form of memory which one have and it is the shortest form of memory.