Answer: C

Explanation:

Kingdom is the highest category in biological classification. It is a group of phyla or divisions having some common characteristics. There are currently five kingdoms: Animalia, Plantae, Fungi, Protista and Monera. Hence statement 2 is correct.

Monera – This kingdom contains unicellular prokaryotic microorganisms which are considered the least organized. Organisms in this kingdom play an important role in the carbon cycle and nitrogen and are metabolically diverse due to their use of substrates such as carbon and energy. Hence statement 1 is correct.

Answer: C

Explanation:

Dengue fever, typhoid, and malaria are all three infectious diseases that can affect humans. Each of these diseases has its own carrier.

•Dengue fever is spread by the bite of Aedes mosquito. Aedes mosquito is a type of mosquito that usually bites during the day or before dusk.

•Typhoid is caused by a bacterium called Salmonella Typhi. This bacteria spreads through consumption of contaminated food or water.

•Malaria is caused by a parasite called Plasmodium. This parasite is spread through the bite of an infected mosquito.

Answer: B

Explanation:

Cancer cells have changes in their genetic material that cause them to grow and divide abnormally compared to normal cells. Hence, statement 1 is correct.

Not all cancers are contagious. Some cancers, such as those caused by sexually transmitted infections (STIs), may be contagious, but others, such as lung cancer or breast cancer, are not. Hence, statement 2 is not correct.

A healthy diet and regular exercise can help reduce the risk of developing cancer. A healthy diet provides the body with essential nutrients, which can help prevent the development of cancer. Regular exercise helps keep the body healthy, which may also help reduce the risk of developing cancer. Hence, statement 3 is correct.

Answer: B

Explanation:

Germ line gene therapy and somatic gene therapy are both used to treat genetic disorders in humans. RNA interference is used in some cases, but it is still in the early stages of development.

Germ line gene therapy is used to change genes in embryos or sperm cells. This change is permanent in all cells, so it may prevent the disorder in future generations. Germ line gene therapy has so far been used only in a few experimental situations, but it has the potential to prevent the birth of genetically disordered children.

Somatic gene therapy is used to change genes in only a single cell or group of cells in the body. This change is limited to only the affected cells, so it cannot prevent the disorder in future generations.

RNA interference is a type of gene therapy that uses RNA to block the function of a gene. RNA interference is being used to treat certain types of cancer, viral infections, and genetic disorders.

Answer: C

Explanation:

The primary role of restriction enzymes in recombinant DNA technology is to facilitate accurate insertion of foreign DNA into the plasmid, a critical step in manipulating and studying genes.