One reason why RNA molecules are the leading candidate as the first informational molecule is that a. some RNA molecules can function as enzymes. b. RNA nucleotides are a major component of cell membranes. c. RNA molecules are usually double stranded. d. RNA serves as the hereditary material in today’s prokaryotic cells.

Explanation:

There are two types of genetic material or nucleic acid RNA and DNA. RNA molecule is considered as first information molecule because of several reasons like -

RNA is less stable than the DNA which shows that a less stable form of genetic material gave rise to a more stable form of genetic material.

One of the most important prove is RNA is catalytic which means it can function as enzymes and can catalyze the reaction which is used to copy genetic material i.e RNA. So the correct answer is a.

fertilization, pictured in figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. the egg and sperm each contain one set of chromosomes. to ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. in mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. when a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. in placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in figure 24.23b. the fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. the nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.

explanation: