Which of the following is an example of a living thing showing autotrophic nutrition? MCQ with Answer and Explanation

Explanation:
Melatonin, synthesized from serotonin, is released in darkness, regulating circadian rhythms and promoting sleep. Serotonin is a neurotransmitter, dopamine reward, acetylcholine muscle contraction.

Explanation:
AUG is the initiation codon and codes for methionine in eukaryotes (formylmethionine in prokaryotes). It signals the start of translation. Arginine codons include CGU, CGC, etc. Alanine is coded by GCU, etc. Glycine by GGU, etc. The genetic code is degenerate, meaning multiple codons can code for the same amino acid, but AUG is unique as the initiator.

Explanation:
In plant tissue culture, when an explant (a piece of plant tissue) is placed on a nutrient medium containing specific plant hormones (like auxins and cytokinins), the cells dedifferentiate and undergo rapid, unorganized division to form a mass of cells called a callus. This callus is undifferentiated. Under appropriate hormonal conditions, this callus can then be induced to redifferentiate and form organized structures like shoots and roots (organogenesis) or somatic embryos.