The extra X chromosome is received from mother.
<h3><u>Explanation</u>:</h3>
Klinefelter's syndrome is the condition of chromosomal aberration where the person has an extra X chromosome. This means the genotype of the person is 44+XXY and the total chromosome number is 47. This condition is achieved due to inappropriate meiotic division and one of the sperm or ovum has the an extra X chromosome.
Here both the parents are normal in terms of colour vision. So the father cannot have the gene of colour blindness because if it was present, then father would have been colour blind because he has only one X chromosome per cell. So its present in mother who is heterozygous in terms of colour blind gene. So the extra X chromosome also came from her which made the presence of two defective X chromosomes in the offspring and made it colour blind.
Answer:
RNA molecules are made of nucleotides. (Ans. C)
Explanation:
RNA, which is also known as ribonucleic acid is found in cytoplasm of the cell, and synthesized in the nucleus. It is shorter, and a single stranded molecule. It is composed of one or more nucleotides which are linked together by phosphodiester bonds.
In RNA, the ribonucleotide contains pentose sugar ribose, four nitrogenous bases (A,U,C,G), and a phosphate group. RNA plays many types of role in cells, but mainly involved in the translation process, and it's regulation which is known as protein synthesis.