Question
What are components of DNA and RNA?
▶️Answer/Explanation
Ans. D
Question
Watson and Crick worked out the three-dimensional structure of DNA.
What did the model they built show for the first time?
A. DNA is a polynucleotide.
B. DNA contains equal quantities of adenine and thymine.
C. DNA molecules have a helical shape.
D. DNA is a double helix with antiparallel sugar–phosphate backbones.
▶️Answer/Explanation
Ans. D
Question
This micrograph is from a dividing cell.
What is shown in this image?
A. Two condensed chromosomes consisting of four chromatids
B. A chromosome from a cell in telophase of mitosis
C. A chromosome from a cell in G1 of interphase
D. A chromosome from a cell in metaphase
▶️Answer/Explanation
Ans: D
Question
Which feature is common to both mRNA and DNA?
A Covalent bonds between adjacent nucleotides
B Hydrogen bonds between guanine and cytosine
C Ribose sugar attached to phosphate
D Antiparallel arrangement of polynucleotide strands
Answer/Explanation
Ans: A
Which structure found in eukaryotes has a single membrane?
A. Nucleus
B. Lysosome
C. Chloroplast
D. Mitochondrion
▶️Answer/Explanation
Markscheme
B
Lysosomes are organelles found in eukaryotic cells that contain digestive enzymes enclosed within a single membrane. They are involved in breaking down and digesting cellular waste materials, foreign substances, and cellular debris. The enzymes inside lysosomes are able to break down various biomolecules, including proteins, lipids, carbohydrates, and nucleic acids.
Question
What is the arrangement of subunits in a DNA nucleotide?
A. sugar – base – phosphate
B. sugar – phosphate – base
C. phosphate – sugar – base
D. sugar – phosphate – base – base – phosphate – sugar
▶️Answer/Explanation
C
Question
What is the arrangement of the components of nucleotides in a single DNA strand?
▶️Answer/Explanation
A
Question
What is the correct arrangement for the components of one strand in a DNA molecule?
▶️Answer/Explanation
C
Question
What is bonded to phosphates in a strand of RNA?
A. Only carbohydrates
B. Adenine, guanine, cytosine and thymine
C. Adenine, guanine, cytosine and uracil
D. Pentoses and bases
▶️Answer/Explanation
A
Question
What are linked by hydrogen bonds?
A. Hydrogen and oxygen within a water molecule
B. Phosphate and sugar within a DNA molecule
C. Base and sugar between DNA nucleotides
D. Hydrogen and oxygen in different water molecules
▶️Answer/Explanation
D