What is the primary function of DNA polymerase?

Correct Answer: B

Rationale: The correct answer is B: Replicating DNA. DNA polymerase is an enzyme responsible for synthesizing new DNA strands during DNA replication. It adds nucleotides to the growing DNA strand based on the template provided by the existing DNA strand. This process ensures that genetic information is accurately copied and passed on to daughter cells during cell division. Option A, Packaging DNA, refers to the coiling and organization of DNA into chromatin, a process involving histones and other proteins. Option C, Transcribing DNA, involves the synthesis of RNA from a DNA template, a process carried out by RNA polymerase. Option D, Translating mRNA, refers to the process of protein synthesis where the information encoded in mRNA is used to assemble amino acids into a polypeptide chain.

Correct Answer: C

Rationale: Amylase is the enzyme responsible for breaking down carbohydrates in the small intestine. It specifically targets starches and sugars, breaking them down into smaller molecules like maltose and glucose that can be absorbed by the body. Pepsin is an enzyme that breaks down proteins in the stomach, not the small intestine. Lipase is responsible for breaking down fats, not carbohydrates. Trypsin is an enzyme that breaks down proteins in the small intestine, not carbohydrates.

Correct Answer: B

Rationale: A) Pectin is a soluble fiber found in fruits and vegetables. It forms a gel-like substance in the gut and can help lower cholesterol levels. B) Cellulose is an insoluble fiber found in plants, particularly in the cell walls of fruits, vegetables, and whole grains. It adds bulk to the stool and promotes gut motility by aiding in the movement of food through the digestive system. C) Beta-glucan is a soluble fiber found in oats and barley. It can help lower cholesterol levels and improve blood sugar control. D) Guar gum is a soluble fiber derived from guar beans. It can help with digestion and may have a role in managing blood sugar levels. In this case, the question specifically asks for the type of fiber that is insoluble and promotes gut motility, which is characteristic of cellulose.

Correct Answer: D

Rationale: A) Gas: Gas is a common symptom of lactose intolerance. When lactose is not properly digested, it can ferment in the colon, leading to the production of gas. B) Bloating: Bloating is another common symptom of lactose intolerance. The buildup of gas in the digestive system can cause bloating and discomfort. C) Diarrhea: Diarrhea is a common symptom of lactose intolerance. When lactose is not broken down in the small intestine, it can draw excess water into the colon, resulting in diarrhea. D) Nausea: Nausea is not a common symptom of lactose intolerance. While some individuals may experience mild stomach discomfort or cramps, nausea is not typically associated with lactose intolerance.

Correct Answer: D

Rationale: Ionic, covalent, and metallic bonds are all types of chemical bonds that involve the sharing or transfer of electrons between atoms. An ionic bond occurs when one atom donates an electron to another, creating positive and negative ions that attract each other. A covalent bond involves the sharing of electrons between atoms to achieve a stable electron configuration. Metallic bonds are formed between metal atoms where electrons are delocalized and move freely among the metal ions. On the other hand, a gravitational bond is not a type of chemical bond. It refers to the force of attraction between two objects with mass, such as the gravitational force between the Earth and objects on its surface. Therefore, the correct answer is 'Gravitational bond.'