A - Ff and Ff is the answer
A variation is a reference to the differences or deviations, such as the structure and form, as for crossing over is the exchange of genetic material between the non-sister chromatids of the homologous chromosomes during meiosis.
Answer:
<em>As scientists learned more about genetics and biochemistry , some organisms were moved out of existing kingdoms and into new ones.</em>
Explanation:
As the researches in the scientific world continued, scientists realized that there were, in fact, many genetic diversities present in organisms which were placed in the same groups. Hence, they realized that due to these differences these organisms should not be kept in the same group. As a result, the groups in the classification system increased.
Carolus Linnaeus just grouped organisms based on their features. But today, scientists classify organisms based on various perspectives such as the evolutionary history, genetic similarities etc.
DNA is a double helix composed of nitrogenous bases, which form hydrogen bonds with each other. It also contains a deoxyribose sugar and phosphate backbone.
<span> An action potential is when a neuron sends information down an axon and keeps it away from the cell body.</span>