Which of the following is not part of the digestive system?

Correct Answer: D

Rationale: The correct answer is 'D: Pancreas.' While the pancreas contributes to digestion by secreting enzymes, it is not part of the main digestive tract. The esophagus, liver, and stomach are integral components of the digestive system. The esophagus helps in the transport of food to the stomach, the stomach aids in food breakdown, the liver produces bile for fat digestion, and the pancreas secretes digestive enzymes. Therefore, the pancreas is the correct answer as it is not part of the primary digestive tract but supports digestion through enzyme secretion.

Correct Answer: D

Rationale: The skin is the largest organ in the human body. It covers the entire body, serving as a protective barrier against pathogens, UV radiation, and physical damage. Additionally, the skin plays a crucial role in regulating body temperature and synthesizing vitamin D when exposed to sunlight. Choices A, B, and C are incorrect. The liver is the largest internal organ, the brain is the control center of the body, and the heart is a vital organ responsible for pumping blood throughout the body. However, none of these organs are the largest in terms of surface area or overall size.

Correct Answer: C

Rationale: Chromosomes, which contain genetic information, are found in the nucleus of a cell. They play a crucial role in cell division, gene expression, and inheritance. Mitochondria, responsible for energy production, are located in the cytoplasm, not the nucleus. The endoplasmic reticulum is mainly involved in protein and lipid synthesis and is not a component of the nucleus. Ribosomes, essential for protein synthesis, are found in the cytoplasm and on the endoplasmic reticulum, but not in the nucleus.

Correct Answer: B

Rationale: The correct function of the liver is to store bile. Bile is produced in the liver and stored in the gallbladder until it is needed to aid in the digestion of fats. While the liver does produce bile, its primary role is to store and release it. Choices A, C, and D are incorrect. Producing digestive enzymes is mainly the function of the pancreas, filtering waste products from the blood is primarily done by the kidneys, and transporting nutrients to cells is typically associated with the circulatory system rather than the liver.

Correct Answer: B

Rationale: The correct answer is B: Cardiac muscle. Cardiac muscle is the specialized muscle found in the walls of the heart. It contracts involuntarily to pump blood throughout the body, ensuring circulation. Smooth muscle is typically found in organs like the intestines and blood vessels, aiding in their functions. Skeletal muscle is attached to bones and plays a vital role in movement and posture. Voluntary muscle is a general term for skeletal muscles that are under conscious control, unlike cardiac muscle which contracts involuntarily to maintain the heart's continuous pumping action.