Answer: Option B - There are more than four genes that determine this trait.
Explanation:
The tobacco plant species have its leaf colour with characteristics that changes gradually over a range of values, which refers to continuous variation.
Note that continuous variation keep expressing gene variants in successive generations of the tobacco plants, that differs from the parents. So, there are MORE THAN four genes controling the expression of varying phenotypes in the leaves
<h2>Answer:</h2>
Bacteria provide genetic engineers with <u>_vector_ </u>and <u>_host_.</u>
<h3>Explanation:</h3>
Vector are vehicles or carriers which are used to carry the gene of interest. They are usually plasmids which are bacterial circular genome which can replicate independently.
Hence bacterial plasmids are used for the insertion of gene of interest and its transfer to the host cell.
As plasmids is taken from the bacteria, so mostly bacteria is used as the host for the gene of interest.
Drives comes from the Biological environment.The Incentive comes from the external environment.
The biological environment is termed as the natural biological environment. For example, plants and wild animals which affects life of human being.
External environment is composed of the outside factors which results in operation of business.
There are two types of external environment. For example, macro environment and micro environment.
Some factors like suppliers, financiers, marketing intermediaries, customers, and public per captions can affect a micro environment.