Which of the following is a respiratory disease caused by a coronavirus? MCQ with Answer and Explanation

Explanation:
Gymnosperms have naked seeds on cones, not in an ovary; hence no fruit. Angiosperms have enclosed seeds. R correctly explains A.

Explanation:
Essential amino acids are those that the human body cannot synthesize in sufficient quantities and must be obtained through the diet. There are nine essential amino acids: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Glycine, alanine, and serine are non-essential amino acids that the body can produce.

Explanation:
The iris is the colored part of the eye containing smooth muscles (sphincter and dilator pupillae) that adjust the pupil diameter to control light entry. The cornea and lens focus, retina senses light.