The protein responsible for muscle contraction are: MCQ with Answer and Explanation

Explanation:
Secretin was the first hormone ever to be identified, marking the birth of endocrinology as a distinct field. It was discovered in 1902 by British physiologists William Bayliss and Ernest Starling. They observed that when acidic chyme entered the duodenum, it stimulated the pancreas to secrete bicarbonate-rich juice, even if all nerves to the pancreas were cut. They concluded that a chemical messenger (which Starling coined the term 'hormone' for in 1905) was released from the intestinal mucosa into the blood to stimulate the pancreas. They named this messenger secretin.

Explanation:
Stomatal transpiration, which occurs through the stomata (pores) on the leaf epidermis, accounts for about 90% of the total water loss in plants. Cuticular transpiration occurs through the waxy cuticle and is minimal. Lenticular transpiration occurs through lenticels in woody stems and is also very small.

Explanation:
Crystallization is a property of non-living substances where molecules arrange in a definite pattern, e.g., salt crystals. Living organisms exhibit growth, reproduction, metabolism, cellular organization, and consciousness. Metabolism is a defining feature of all living organisms, occurring even in unicellular forms. Reproduction, though absent in sterile organisms like mules, is generally a characteristic. Growth in living beings is internal and intrinsic, unlike extrinsic accumulation in non-living things. Hence, crystallization is not a characteristic of life.