Starfish carry out movements with the help of tube feet that are part of the water vascular system. Apart from their function in locomotion, the tube feet act as accessory gills. The water vascular system serves to transport oxygen from, and carbon dioxide to, the tube feet and also nutrients from the gut to the muscles involved in locomotion.

Correct Option: A

Starfish carry out movements with the help of tube feet that are part of the water vascular system. Apart from their function in locomotion, the tube feet act as accessory gills. The water vascular system serves to transport oxygen from, and carbon dioxide to, the tube feet and also nutrients from the gut to the muscles involved in locomotion.

Riboflavin, also known as vitamin B₂, is one of the eight B-complex vitamins. It is a water-soluble vitamin that functions as a coenzyme, meaning that it is required for enzymes (proteins) to perform normal physiological actions. Riboflavin is found in milk, cheese, eggs, leaf vegetables, liver, kidneys, legumes, mushrooms, and almonds.

Correct Option: A

Riboflavin, also known as vitamin B₂, is one of the eight B-complex vitamins. It is a water-soluble vitamin that functions as a coenzyme, meaning that it is required for enzymes (proteins) to perform normal physiological actions. Riboflavin is found in milk, cheese, eggs, leaf vegetables, liver, kidneys, legumes, mushrooms, and almonds.

Insectivorous plants trap insects because they grow in a soil which is deficient in nitrogen (such as acidic bogs and rock outcrops). The insects they feed on help them in fulfilling their nitrogen needs. Venus flytrap, pitcher plant, utricularia, drosera and Rafflesia are the examples of insectivorous plants.

Correct Option: A

Insectivorous plants trap insects because they grow in a soil which is deficient in nitrogen (such as acidic bogs and rock outcrops). The insects they feed on help them in fulfilling their nitrogen needs. Venus flytrap, pitcher plant, utricularia, drosera and Rafflesia are the examples of insectivorous plants.

Xylem parenchyma is the only living component found in xylem tissue. They are living cells associated with the xylem that are found in between the vessels and the fibers. They act as storage house of starch and fat with assisting in conduction of water. Xylem is a complex permanent tissue specialized for the conduction of water and mineral substances in plants.

Correct Option: C

Xylem parenchyma is the only living component found in xylem tissue. They are living cells associated with the xylem that are found in between the vessels and the fibers. They act as storage house of starch and fat with assisting in conduction of water. Xylem is a complex permanent tissue specialized for the conduction of water and mineral substances in plants.

The main source of atmospheric free oxygen is photosynthesis, which produces sugars and free oxygen from carbon dioxide and water. The organisms that carry out photosynthesis include the plant life of the land areas as well as the phytoplankton of the oceans. 6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂

Correct Option: A

The main source of atmospheric free oxygen is photosynthesis, which produces sugars and free oxygen from carbon dioxide and water. The organisms that carry out photosynthesis include the plant life of the land areas as well as the phytoplankton of the oceans. 6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂