Read the following statements.

I. Pigs are being developed for use in testing the safety of vaccines before they are used on humans.

II. A transgene is a foreign gene that, when incorporated into a host cell, makes it transgenic.

III. ADA deficiency leads to Severely Combined Immuno Deficiency (SCID).

IV. The two insulin polypeptides are connected through hydrogen bonds.

Which of the above statements are correct?

II and III

I. Transgenic mice are being developed for use in testing the safety of vaccines before they are used on humans. Transgenic mice are being used to test the safety of the polio vaccine. If successful and found to be reliable, they could replace the use of monkeys to test the safety of batches of the vaccine.

II. A transgene is a foreign gene that, when incorporated into a host cell, makes it transgenic is correct .

A transgene is a gene that comes from a different species or organism and is introduced into the genome of another organism, known as the host cell. When the host cell incorporates this foreign gene, it becomes transgenic, as it now contains genetic material from two different sources. The introduction of transgenes is a fundamental process in genetic engineering, enabling the manipulation of an organism's genetic makeup to introduce specific traits or functions.

III. ADA deficiency causes Severely Combined Immuno Deficiency (SCID) is correct.

ADA deficiency is a genetic disorder that results from the lack of the enzyme adenosine deaminase (ADA) in the body. This enzyme is essential for the normal functioning of the immune system. Without ADA, the immune system is severely impaired, leading to a condition known as Severe Combined Immuno Deficiency (SCID). SCID is characterized by a severely weakened immune system, making affected individuals highly susceptible to infections and illnesses.

IV. The two insulin polypeptides are cross-linked via hydrogen bonds is incorrect .

Insulin is a hormone produced by the pancreas that plays a crucial role in regulating blood sugar levels. It is composed of two polypeptide chains, referred to as chain A and chain B. These chains are connected to each other through disulfide bridges, not hydrogen bonds. The disulfide bridges help maintain the three-dimensional structure of insulin, allowing it to function effectively in the body to regulate glucose metabolism.