The answer is A. - Prokatyotic cells lack a defined nucleus while eukaryotic cells do have one :) I loved learning about the cells in biology! But I noticed your question is worded a little differently so the nucleus would be the one thing a eukaryotic cell has that a prokatyotic cell does not...
<span>The discoverers of DNA were not James
D Watson and Francis Crick. They are the first scientist to formulate an
accurate description of the DNA’s (deoxyribonucleic acid) complex ,
double-helical structure. They discovered that base pairing nucleotides must
be; adenine and thymine; and cytosine and guanine. These base pairs are held
together by a hydrogen bond, atype of chemical reaction that s easy to break
and easy to reform. The statement is “DNA
is a double helix made of two strands linked together with hydrogen
bonds.”</span>
C. Lactic acid fermentation
After crystal violet staining, the Gram-positive bacteria may appear dark blue or violet. The cell wall of gram positive bacteria have thick peptidoglycan layer, thus it retains the crystal violet stain compared to gram negative bacteria.
