The head of a phospholipid can be described as a-polar and hydrophobic b-hydrophobic with a negative charge c-polar and hydrophilic d-nonpolar and hydrophilic

C-polar and hydrophilic

Explanation:

Phospholipids are the amphipathic molecules and have both polar and non-polar parts in their structure. The phospholipid head is a polar and hydrophilic part which makes the outer part of the bilayer in the cell membrane. The phospholipid tails are non-polar and hydrophobic and are buried in the core of the bilayer to stay away from water.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus.

this is so because calcium carbonate is the main component in the shells. calcium carbonate is strengthened by phosphorus.

explanation:

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