If you're talking about eukaryotic cells then it's the cell wall. If it's a prokaryotic cell sometimes the slime layer secreted by some bacteria may harden and form a capsule around the bacterial cell.
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Calcareous ooze<span> is a form of calcium carbonate derived from planktonic organisms that accumulates on the sea floor. ... Below this depth, calcium carbonate begins to dissolve in the ocean, and only non-</span>calcareous<span> sediments are stable, such as</span>siliceous ooze<span> or pelagic red clay.</span>
Answer:
first give the following options bro..
Answer: Memory B cells
Explanation:
Memory B cells remember the same pathogen for faster antibody production in future infections.