MCQ
Eutrophication causes $a/ an:$
- ADecrease in organic matter.
- BIncrease in inorganic nutrients.
- ✓Decrease in dissolved oxygen.
- DIncrease in dissolved oxygen.
✓
Answer
Correct option: C.
Decrease in dissolved oxygen.
Decrease in dissolved oxygen.
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Insulin used to cure diabetes was earlier extracted from pancreas of slaughtered cattle and pigs. Insulin extracted from an animal source, though caused some patients to develop allergy or other types of reactions to the foreign protein. Human insulin consists of two short polypeptide chains : chain $A$ and chain $B$, that are linked together by disulphide bridges. In mammals including humans, insulin is synthesised as a pro$-$hormone which contains an extra stretch called the $C-$peptide. This $C$ peptide is not present in mature insulin and is removed during maturation into insulin.
→Insulin used to cure diabetes was earlier extracted from pancreas of slaughtered cattle and pigs. Insulin extracted from an animal source, though caused some patients to develop allergy or other types of reactions to the foreign protein. Human insulin consists of two short polypeptide chains : chain $A$ and chain $B$, that are linked together by disulphide bridges. In mammals including humans, insulin is synthesised as a pro$-$hormone which contains an extra stretch called the $C-$peptide. This $C$ peptide is not present in mature insulin and is removed during maturation into insulin.
- Identify $A$ in the given figure.
- Polypeptide chain $A.$
- Polypeptide chain $B.$
- Polypeptide chain $C.$
- None of these.
- The following is a list of some stages involved in producing human insulin from genetically engineered bacteria.
- The bacteria are cultured in a fermenter for large scale production.
- Recombinant insulin is extracted from the bacterial cells that expresses insulin gene.
- The same restriction enzyme is used again to cut the bacterial plasmid for insertion of the human insulin gene.
- Bacteria take up the plasmid carrying the insulin gene.
- A restriction enzyme is used to cut human $\text{DNA}$ to extract the insulin gene.
- $1, 5, 3, 4, 2$
- $2, 4, 3, 5, 1$
- $4, 5, 3, 2, 1$
- $5, 3, 4, 1, 2$
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- $\text{DNA}$ ligase is able to join the segments of human and bacterial $\text{DNA.}$
- The exact length of nucleotides matching the insulin gene is removed from the plasmid.
- Both the bacterial and human $\text{DNA}$ will contain sticky ends.
- Sticky ends in the cut plasmid and insulin gene are complementary.
- Why is the fermentor important for the production of human insulin by transgenic bacteria?
- It provides optimal conditions for the transgenic to multiply rapidly.
- It facilitates the extraction and purification of insulin from the transgenic bacteria.
- It maximise the rate of fermentation of the transgenic bacteria.
- It provides the low$-$oxygen conditions that are important for insulin production.
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- Bacteria with the $\text{rDNA}$ will not be able to form colonies in a fermenter.
- The resulting plasmids are not able to enter the $E.$coli bacteria even after applying heat shock.
- The resulting $E.$coli bacteria do not contain the human insulin gene.
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