A closer look at the interactions between the histones and the nucleosomal DNA reveals the structural basis for the binding and bending of the DNA within the nucleosome. Fourteen distinct sites of contact are observed, one for each time the minor groove of the DNA faces the histone octamer. State whether the following set of statements is true/false regarding this association?

I. The majority of these associations are between the proteins and the oxygen atoms in the phosphodiester backbone near the minor groove of the DNA.

II. The association of DNA with the nucleosome is mediated by a large number (about 40) of hydrogen bonds between the histones and the DNA.

III. Maximum numbers of hydrogen bonds are made between the protein side chains and the bases, and all of these are made in the minor groove of the DNA.

IV. The highly basic nature of the histones further facilitates DNA bending by masking the negative charge of the phosphates that ordinarily resists DNA bending.

V. The positively charged nature of the histones facilitates the close juxtaposition of the two adjacent DNA helices necessary to wrap the DNA more than once around the histone octamer.

#Question id: 3564

#Unit 8. Inheritance Biology

Population locus with four alleles. How many genotypes are present in the population?

#Question id: 3565

#Unit 8. Inheritance Biology

Mendel crossed yellow-seeded and green-seeded pea plants and then allowed the offspring to self-pollinate to produce an F2 generation. The results were as follows: 6,022 yellow and 2,001 green. Which of the following statements correctly describes the relationship of the allele for green seeds to the allele for yellow seeds?

#Question id: 3566

#Unit 8. Inheritance Biology

Two organisms, with genotypes BbDD and BBDd, are mated. Assuming independent assortment of the B/b and D/d genes, determine the genotypic ratios in offspring that would occur.

#Question id: 3567

#Unit 8. Inheritance Biology

Cross is made between a pure breeding plant having red coloured flowers with a pure breeding plant having white coloured flowers. All of these offspring are red colored flower. Upon selfing of these F1 red flower plant produced both red and white flower. Which of the following is not a conclusion of these cross?

#Question id: 3568

#Unit 8. Inheritance Biology

You begin to study a novel plant species and discover that this diploid plant has 16 chromosomes. How many linkage groups would you expect to find?

#Question id: 3569

#Unit 8. Inheritance Biology

Haploid cells in the human body: