Question

Plant named Red Aglaonema has leaves which are red in colour. The red colour is due to the presence of
A. Chlorophyll
B. Carotenoids
C. Haemoglobin
D. Calcium

Answer 1

Hint: The bulk of Aglaonema propagation is achieved with cuttings and by separating the basal shoots. They have red coloured leaves as it contains the same pigment carrots have.

Complete answer: Aglaonema is a genus in the arum family, Araceae, of flowering plants. Aglaonema is widely known as Chinese evergreens. In plants, algae, and photosynthetic bacteria, carotenoids are pigments. The bright yellow, red, and orange colours of plants, vegetables, and fruit are created by these pigments. For humans, carotenoids function as a form of antioxidant. Carotenoids are water-repelling pigments with a very long chain that are synthesized in the plastids of plant cells. The sunflower produces a popular carotenoid, beta-carotene, to produce vivid yellow-orange colours in the chromoplasts of the ray flowers. A pigment mainly responsible for photosynthesis that imparts green colour is chlorophyll. In leaves called carotenoids, other pigments are also present. Carotenoids range from red to orange to yellow in colour. The blue wavelength mainly absorbs these pigments, allowing the longer wavelengths to be spread and the yellow colour to be formed. The carotenoids are leftover in the chloroplasts in the autumn foliage and revealed from chlorophyll loss. Light is absorbed maximally by carotenoids between 460 nm and 550 nm and appears red, orange or yellow in colour.
So, option B is the correct answer.

Note: Carotenoids are called accessory pigments that help to absorb photons for photosynthesis. But it has become evident over the past 30 years that they have a second role, no less significant than the first. And that is to redirect excess energy away from the molecules of chlorophyll.