भारतीय जनता में लगभग कितने प्रतिशत व्यक्तियों में Rh- ऋणात्मक (Rh-) तत्व होता है?

Which of the following statements are correct with reference to packaging of DNA helix? A. Histones are organized to form a unit of eight molecules called histone octamer. B. Histones are negatively charged basic proteins. C. Histones are rich in the basic amino acid residues - lysine and arginine. D. The positively charged DNA is wrapped around the histone octamer to form nucleosome. E. The packaging of chromatin at higher levels requires an additional set of proteins called non-histone chromosomal proteins. Choose the correct answer from the options given below:

Which of the following statements are true with reference to sex-determination in honeybees? A. An offspring formed from the union of a sperm and an egg develops as a female (queen or worker). B. An unfertilized egg develops as a male by parthenogenesis. C. A male has half the number of chromosomes than that of a female. D. Males produce sperms by meiosis. E. Honeybees have a haplodiploid sex-determination system. Choose the correct answer from the options given below:

Match List I with List II: List I: A. Incomplete dominance B. Co-dominance C. Pleiotropy D. Polygenic inheritance List II: I. Human skin color II. Inheritance of flower color in Antirrhinum sp. III. Phenylketonuria disease in humans IV. ABO blood groups Choose the correct answer from the options given below:

Which one of the following disorders is caused by the substitution of Glutamic acid (Glu) by Valine (Val) at the sixth position of the beta-globin chain of the hemoglobin molecule?

Which of the following statements are correct with reference to a transcription unit? A. A transcription unit in DNA is defined primarily by three regions: promoter, structural gene and terminator. B. The promoter is said to be located towards the 5'-end of the structural gene (with respect to coding strand). C. The promoter is a DNA sequence that provides binding site for RNA polymerase. D. The promoter defines the template and coding strands. E. The terminator is located towards the 3'-end of the coding strand and it defines the end of the process of transcription. Choose the correct answer from the options given below:

The development of antibiotic resistance in bacterial populations poses significant challenges for modern medicine and primarily exemplifies which of the following biological processes?

Which evolutionary process involves the transfer of genetic material between separate populations through migration and interbreeding?

Which evolutionary mechanism causes random shifts in allele frequencies within small populations over generations?