BIO 131 Challenge Exam Study Guide Quizzes
Latest 2026 With Answers
Components of an atom
Atoms consist of protons, neutrons, and electrons. Protons and neutrons form the nucleus, while
electrons orbit around the nucleus.
Most abundant atoms in living things
The most abundant atoms in living organisms are carbon, hydrogen, oxygen, nitrogen,
phosphorus, and sulfur.
Covalent vs. non-covalent bonds
Covalent bonds involve the sharing of electron pairs between atoms, while non-covalent bonds
include ionic, hydrogen, and van der Waals interactions that do not involve electron sharing.
Types of chemical bonds
Chemical bonds include hydrogen bonds (attraction between polar molecules), ionic bonds
(attraction between charged ions), and hydrophobic forces (interaction of nonpolar substances in
water).
Importance of pH, acids, and buffers in the lab
pH affects enzyme activity and chemical reactions; buffers help maintain stable pH levels in
biological and chemical systems.
Basics of solutions and dilutions
,A solution consists of a solute (substance dissolved) and a solvent (substance doing the
dissolving). Concentration is the amount of solute per volume of solution, often expressed in
moles per liter (Molar) or percent solution.
Monomers and polymers of major macromolecules
Monomers are the building blocks of polymers; for example, amino acids are monomers of
proteins, nucleotides are monomers of nucleic acids, and monosaccharides are monomers of
carbohydrates.
Major functions of macromolecules
Proteins serve as enzymes and structural components, nucleic acids store and transmit genetic
information, carbohydrates provide energy and structural support, and lipids store energy and
form cell membranes.
Sugar-phosphate backbone of DNA
The sugar-phosphate backbone of DNA consists of alternating sugar (deoxyribose) and
phosphate groups, with nitrogenous bases (A, T, G, C) attached to the sugars.
Interaction of bases A, T, G, C
Adenine (A) pairs with Thymine (T) through two hydrogen bonds, while Guanine (G) pairs with
Cytosine (C) through three hydrogen bonds.
Central Dogma
The Central Dogma of molecular biology describes the flow of genetic information from DNA to
RNA (transcription) and from RNA to protein (translation).
, Differences between DNA and RNA
DNA is double-stranded, contains deoxyribose sugar, and uses thymine (T), while RNA is
single-stranded, contains ribose sugar, and uses uracil (U) instead of thymine.
Location of transcription and translation in the cell
Transcription occurs in the nucleus, while translation occurs in the cytoplasm on ribosomes.
How mRNA codes for proteins
mRNA is transcribed from DNA and carries the genetic code, which is translated into a specific
sequence of amino acids to form proteins.
Drawing mRNA from DNA
To draw mRNA from DNA, transcribe the DNA sequence by replacing thymine (T) with uracil
(U) and maintaining the complementary base pairing.
Important enzymes in DNA science
Key enzymes include DNA polymerase (replicates DNA), RNA polymerase (synthesizes RNA),
and restriction enzymes (cut DNA at specific sequences).
How enzymes work
Enzymes act as catalysts to speed up chemical reactions by lowering the activation energy
required, but they can be inhibited by factors like temperature, pH, or substrate concentration.
Important enzymes like DNA polymerase
DNA polymerase synthesizes new DNA strands during replication, while RNA polymerase
synthesizes RNA from a DNA template.
Latest 2026 With Answers
Components of an atom
Atoms consist of protons, neutrons, and electrons. Protons and neutrons form the nucleus, while
electrons orbit around the nucleus.
Most abundant atoms in living things
The most abundant atoms in living organisms are carbon, hydrogen, oxygen, nitrogen,
phosphorus, and sulfur.
Covalent vs. non-covalent bonds
Covalent bonds involve the sharing of electron pairs between atoms, while non-covalent bonds
include ionic, hydrogen, and van der Waals interactions that do not involve electron sharing.
Types of chemical bonds
Chemical bonds include hydrogen bonds (attraction between polar molecules), ionic bonds
(attraction between charged ions), and hydrophobic forces (interaction of nonpolar substances in
water).
Importance of pH, acids, and buffers in the lab
pH affects enzyme activity and chemical reactions; buffers help maintain stable pH levels in
biological and chemical systems.
Basics of solutions and dilutions
,A solution consists of a solute (substance dissolved) and a solvent (substance doing the
dissolving). Concentration is the amount of solute per volume of solution, often expressed in
moles per liter (Molar) or percent solution.
Monomers and polymers of major macromolecules
Monomers are the building blocks of polymers; for example, amino acids are monomers of
proteins, nucleotides are monomers of nucleic acids, and monosaccharides are monomers of
carbohydrates.
Major functions of macromolecules
Proteins serve as enzymes and structural components, nucleic acids store and transmit genetic
information, carbohydrates provide energy and structural support, and lipids store energy and
form cell membranes.
Sugar-phosphate backbone of DNA
The sugar-phosphate backbone of DNA consists of alternating sugar (deoxyribose) and
phosphate groups, with nitrogenous bases (A, T, G, C) attached to the sugars.
Interaction of bases A, T, G, C
Adenine (A) pairs with Thymine (T) through two hydrogen bonds, while Guanine (G) pairs with
Cytosine (C) through three hydrogen bonds.
Central Dogma
The Central Dogma of molecular biology describes the flow of genetic information from DNA to
RNA (transcription) and from RNA to protein (translation).
, Differences between DNA and RNA
DNA is double-stranded, contains deoxyribose sugar, and uses thymine (T), while RNA is
single-stranded, contains ribose sugar, and uses uracil (U) instead of thymine.
Location of transcription and translation in the cell
Transcription occurs in the nucleus, while translation occurs in the cytoplasm on ribosomes.
How mRNA codes for proteins
mRNA is transcribed from DNA and carries the genetic code, which is translated into a specific
sequence of amino acids to form proteins.
Drawing mRNA from DNA
To draw mRNA from DNA, transcribe the DNA sequence by replacing thymine (T) with uracil
(U) and maintaining the complementary base pairing.
Important enzymes in DNA science
Key enzymes include DNA polymerase (replicates DNA), RNA polymerase (synthesizes RNA),
and restriction enzymes (cut DNA at specific sequences).
How enzymes work
Enzymes act as catalysts to speed up chemical reactions by lowering the activation energy
required, but they can be inhibited by factors like temperature, pH, or substrate concentration.
Important enzymes like DNA polymerase
DNA polymerase synthesizes new DNA strands during replication, while RNA polymerase
synthesizes RNA from a DNA template.
