B.6A - DNA

How is information for a specific protein carried on the DNA molecule?

• As a sequence of nucleotides

• In the double-helix shape of the condensed chromosome

• In the ratio of adenines to thymines

• As a pattern of phosphates and sugars

Which part of a DNA molecule is responsible for the direct coding of specific traits in an organism?

• The number of hydrogen bonds that hold the strands of DNA together.

• The number of carbons in the DNA molecule.

• The sequence of nucleotide bases in the DNA molecule.

• The sequences of phosphates along each DNA strand.

How does DNA in cells determine an organism’s complex traits?

• DNA contains codes for proteins, which are necessary for the growth and functioning of an organism.

• DNA separates into long single strands that make up each part of an organism.

• DNA produces the energy an organism needs in order to grow.

• DNA folds into the nucleus of each of the cells of an organism.

Which of the following nucleotides is NOT found in DNA?

• thyamine

• cytosine

• uracil

• guanine

Nucleotides are composed of a phosphate group, a sugar, and a nitrogenous base. DNA is made up of long strands of nucleotides. Which part of the above molecule can differ between nucleotides?

• the sugar

• the phosphate group

• the nitrogenous base

• there is no differing structure in nucleotides

Twin colts were born from a black mare and a black stallion. One colt was black, one was brown. What is the most likely reason for the difference in the traits of the two colts?

• They inherited different numbers of chromosomes.

• They inherited different amounts of DNA.

• They inherited different nucleotide sequences.

• A mutagen altered the sequence of nucleotides in the brown colt.

Which of the following provides growth and development information to cells?

• deoxyribonucleic acid

• polymerase

• adenosine triphosphate

• cell adhesion molecules

5’ TTAGCG 3’

Which of the following nucleotide base sequences complements the section of DNA modeled above?

• 5’ UTCGCA 3’

• 3’ AATCGC 5’

• 5’ GCGATT 3’

• 5’ TTUCGC 3’

A biologist collects DNA samples from two sisters. The younger sister has blond hair. The older sister has red hair. The sisters have different traits because their DNA contains different —

• orders of nucleotides

• types of sugar molecules

• sized phosphate groups

• nitrogenous base

One strand in a molecule of DNA contains the sequence below.

ATTGCGTA

Which sequence is the complementary strand?

• ATTGCGTA

• UAACGCAU

• TAACGCAT

• GCCTATCG