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.
Answer:
The correct is B Hormones are chemical signals between cells transported in blood or hemolymph.
Explanation:
Hormones are called chemical messenger of the cell because they transmit chemical information from one cell to the target cell and regulating the functioning of that target cell by activating specific proteins related to the functioning of that target cell.
Hormone is secreted from its source gland such as Pituitarygland, thyroid gland,adrenal gland.After being secreted hormones are transported via the blood stream to the target cell and binds to receptor of that target cell thus allowing the target cell to exert its biological function.
I would say c would be the best.
Answer:
C)
Explanation:
Meiosis creates sex cells (gametes) for sexual reproduction. And the resulting daughter cells have have the number of chromosomes as the parent cell.