D Oxygen binding occurs in the cleft where the polypeptides come into contact. Question 6 1 Point Which of the following statements about DNA are true? Select all that apply. Ticking all the boxes will result in a mark of zero for this question. A A-form and B-form DNA are right-handed helices, but Z-form DNA is a left handed helix found only in single-stranded DNA. B Palindromic sequences can potentially form cruciform structures. C "The dideoxy method of sequencing DNA can be used on B-DNA, but not on Z-DNA. D Deoxyribose is bound to the nitrogenous base at C-1'. E A pyrimidine in one strand of DNA always hydrogen bonds with a purine in the opposite strand. The phosphodiester bonds that link adjacent nucleotides join the 3' hydroxyl of one nucleotide to the 5' hydroxyl of the F next. G All the monosaccharide units lack an -OH at C-2'. Question 7 1 Point