The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. It allows the transfer of nutrients and oxygen from the mother to the fetus and the transfer of waste products and carbon dioxide back from the fetus to the maternal blood supply. Nutrient transfer to the fetus occurs via both active and passive transport.

Correct Option: B

The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. It allows the transfer of nutrients and oxygen from the mother to the fetus and the transfer of waste products and carbon dioxide back from the fetus to the maternal blood supply. Nutrient transfer to the fetus occurs via both active and passive transport.

Photosynthesis is a process used by plants and other organisms to convert the light energy captured from the sun into chemical energy that can be used to fuel the organism's activities. The general equation for photosynthesis is therefore: Carbon dioxide + electron donor + light energy ® carbohydrate + oxidized electron donor.

Correct Option: B

Photosynthesis is a process used by plants and other organisms to convert the light energy captured from the sun into chemical energy that can be used to fuel the organism's activities. The general equation for photosynthesis is therefore: Carbon dioxide + electron donor + light energy ® carbohydrate + oxidized electron donor.

Quinine, as a component of the bark of the cinchona tree, was used to treat malaria from as early as the 1600s. The bark of trees in this genus is the source of a variety of alkaloids, the most familiar of which is quinine, an antipyretic (anti-fever) agent.

Correct Option: B

Quinine, as a component of the bark of the cinchona tree, was used to treat malaria from as early as the 1600s. The bark of trees in this genus is the source of a variety of alkaloids, the most familiar of which is quinine, an antipyretic (anti-fever) agent.

The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.

Correct Option: B

The Iodine test is used to test for the presence of starch. Iodine solution — iodine dissolved in an aqueous solution of potassium iodide — reacts with the starch producing a purple black colour.

In onions, the bulbs consist of very short stems with closely packed leaves arranged in concentric circles round the stem. These leaves are swollen with stored food. The inner leaves are fleshy while the outer ones are dry. This is called as tunicated bulb since the concentric leaf bases form a complete covering or tunic.

Correct Option: C

In onions, the bulbs consist of very short stems with closely packed leaves arranged in concentric circles round the stem. These leaves are swollen with stored food. The inner leaves are fleshy while the outer ones are dry. This is called as tunicated bulb since the concentric leaf bases form a complete covering or tunic.