Nucleic Acids Biology Quiz

Nucleic Acids

• Nucleic acids store, transmit, and help express hereditary information.
• The amino acid sequence of a polypeptide is programmed by a gene.
• Genes are made of DNA, a nucleic acid composed of nucleotides.
• DNA provides directions for its own replication.
• DNA directs the synthesis of messenger RNA (mRNA), which then controls protein synthesis.
• Protein synthesis occurs on ribosomes.
• There are two types of nucleic acids: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

Components of Nucleic Acids

• Nucleic acids are polymers called polynucleotides.
• Each polynucleotide is made of monomers called nucleotides.
• Each nucleotide consists of a nitrogenous base, a pentose sugar, and one or more phosphate groups.
• The portion of a nucleotide without the phosphate group is called a nucleoside.

Nucleotide Polymers

• Nucleotide polymers are linked together to form a polynucleotide.
• Adjacent nucleotides are joined by covalent bonds between the -OH group on the 3' carbon of one nucleotide and the phosphate on the 5' carbon of the next.
• These links form a sugar-phosphate backbone with nitrogenous bases as appendages.
• The sequence of bases along a DNA or mRNA polymer is unique for each gene.

Structures of DNA and RNA Molecules

• RNA molecules usually exist as single polypeptide chains.
• DNA molecules have two polynucleotide strands that spiral around each other, forming a double helix.
• In the DNA double helix, the two backbones run in opposite 5'→3' directions (antiparallel).
• One DNA molecule includes many genes.

DNA and Protein as Evolutionary Measures

• The linear sequences of nucleotides in DNA molecules are passed from parents to offspring.
• Two closely related species show more similarity in their DNA than distantly related species.
• Molecular biology can be used to evaluate evolutionary relationships between species.

Nitrogenous Bases

• The nitrogenous bases in DNA pair up through hydrogen bonds: adenine (A) with thymine (T), and guanine (G) with cytosine (C).
• In RNA, thymine is replaced by uracil (U), so adenine (A) pairs with uracil (U).
• Complementary base pairing can occur between two RNA molecules or between parts of the same molecule.

Test your knowledge on nucleic acids, their structure, and function in heredity. This quiz covers essential concepts including DNA and RNA compositions, protein synthesis, and the role of nucleotides. Challenge yourself with questions that delve into the molecular foundation of genetics.