Lac genes are most effectively expressed in presence of Lactose and its analogs when glucose is absent.
Explanation:
A unit of prokaryotic gene expression and regulation,which includes structural genes and regulatory sequences recognized by regulatory gene product is called operon.
<em>Lac </em>structural genes are a part of<em> Lac</em> operon. The <em>Lac </em>operon consists of three, structural genes,an operator and a promoter.The product of Lac operon is involved in the conversion of disaccharide lactose into glucose and Galactose.
Lactose and its analogs are inducers of<em> Lac </em>operon. So, the structural genes are best expressed in presence of Lactose. Glucose and galactose are repressors of lac gene so the genes are repressed in presence of glucose.
The alveoli. These little air sacs are found on the end of the bronchioles and are the place where oxygen enters the blood and the carbon dioxide leaves.
The wing of a bat is homologous to the flipper of a whale. Homologous structures are structures that have a similar ancestries and common traits but maybe not have the same function in an organism. For example the arm of a human, the wing of a bird or a bat, the leg of a dog and the flipper of a dolphin or whale are homologous structures.
In general, Yes True <span />
Eutrophication can result from excess nutrients pollution in bodies of water
