The correct answer is: A. Nondisjunction
Let me know if this helped :)
C. Agar provides a solid surface for bacterial growth.
Agar is a substance obtained from red algae which when added to a culture media, provides a solid surface for the growth of bacteria. When the agar is not added then the culture media remains as the broth and when the agar is added then the broth gets solidified.
Agar is added 1.5-2% in the broth to get solidified. The growth of the bacteria depends on the amount of agar added. Agar is used for the growth of bacteria because it has gel like properties which holds the nutrients evenly and the bacteria can use it accordingly.
Vitamins refers to the components, which the body requires to develop and grow normally. There are in total 13 vitamins required by the body. These are classified as food soluble and water soluble vitamins.
It is generally advised to consume vitamins on a daily basis because the body has limited tendency of storage for various vitamins. Thus, they should be consumed on a regular basis in the diet.
A single animal cell ( like a red blood cell) placed in a hypotonic solution will fill up with water and then burst.
As a result the bacterial cells switch off transcription of genes involved in the production of tryptophan because the amino acid binds to the REPRESSOR.