The actual site of gas exchange in the mammalian respiratory system is: MCQ with Answer and Explanation

Explanation:
Cones are photoreceptor cells in the retina responsible for photopic (daylight) vision and color perception. There are three types of cones sensitive to blue, green, and red wavelengths. Rods are responsible for scotopic (dim light) vision and do not detect color. The cornea and lens focus light onto the retina.

Explanation:
The pancreas, liver, and salivary glands are accessory digestive glands that secrete enzymes or substances aiding digestion into the alimentary canal. The pancreas produces pancreatic juice (enzymes and bicarbonate) released into the duodenum. The stomach and small intestine are part of the main digestive tract, and the esophagus is a conduit for food.

Explanation:
Photosynthesis consists of light-dependent reactions occurring in the thylakoid membranes (grana) where water is split, releasing oxygen, and light-independent reactions (Calvin cycle) occurring in the stroma where CO2 is fixed. The oxygen released during photosynthesis comes from the photolysis of water, not from carbon dioxide. Thus, statements 1 and 2 are correct.