BIO 242 LATEST 2026 EXAM QUESTIONS AND ANSWERS
GRADED A+
✔✔Selective environment - ✔✔Environmental factors that influence which traits are
favored
✔✔Phylogenetic tree - ✔✔Diagram showing evolutionary relationships among species
✔✔Node - ✔✔Point on a phylogenetic tree representing a common ancestor
✔✔Clade - ✔✔Group consisting of an ancestor and all its descendants
✔✔Most recent common ancestor - ✔✔The most recent individual shared by two
lineages
✔✔Endosymbiont theory - ✔✔Theory that mitochondria and chloroplasts evolved from
bacteria
✔✔Evidence for endosymbiosis - ✔✔Own DNA, double membranes, bacterial size,
independent replication
✔✔Protein - ✔✔Functional molecule made of one or more polypeptides
✔✔Polypeptide - ✔✔Chain of amino acids encoded by a gene
✔✔Amino acid - ✔✔Building block of proteins
✔✔Primary protein structure - ✔✔Linear sequence of amino acids
✔✔Secondary protein structure - ✔✔Alpha helices and beta sheets formed by hydrogen
bonding
✔✔Tertiary protein structure - ✔✔Overall 3D shape formed by side-chain interactions
✔✔Quaternary protein structure - ✔✔Protein structure formed from multiple polypeptide
subunits
✔✔Peptide bond - ✔✔Covalent bond linking amino acids together
✔✔R group - ✔✔Side chain of an amino acid that determines its chemical properties
✔✔Nonpolar side chains - ✔✔Hydrophobic amino acids typically found inside proteins
, ✔✔Polar or charged side chains - ✔✔Hydrophilic amino acids typically found on protein
surfaces
✔✔DNA - ✔✔Double-stranded nucleic acid storing genetic information
✔✔Nucleotide - ✔✔Building block of DNA or RNA
✔✔Complementary base pairing - ✔✔A pairs with T; G pairs with C
✔✔Chargaff's rules - ✔✔Amounts of A=T and G=C in DNA
✔✔Semiconservative replication - ✔✔Each new DNA molecule contains one old strand
and one new strand
✔✔RNA - ✔✔Single-stranded nucleic acid involved in gene expression
✔✔mRNA - ✔✔RNA that carries genetic instructions from DNA to ribosome
✔✔tRNA - ✔✔RNA that brings amino acids to the ribosome during translation
✔✔Central dogma - ✔✔Flow of genetic information from DNA to RNA to protein
✔✔Transcription - ✔✔Process of making RNA from a DNA template
✔✔Translation - ✔✔Process of building a protein from an mRNA sequence
✔✔Gene regulation - ✔✔Control of when and how much a gene is expressed
✔✔Operon - ✔✔Prokaryotic gene regulation system with coordinated gene control
✔✔Promoter - ✔✔DNA sequence where RNA polymerase binds
✔✔Operator - ✔✔DNA site where repressors bind in operons
✔✔Repressor - ✔✔Protein that blocks transcription
✔✔Activator - ✔✔Protein that increases transcription
✔✔Enhancer - ✔✔DNA region that increases transcription in eukaryotes
✔✔Genome - ✔✔Complete set of genetic material in an organism
✔✔Gene - ✔✔Segment of DNA that encodes a functional product
GRADED A+
✔✔Selective environment - ✔✔Environmental factors that influence which traits are
favored
✔✔Phylogenetic tree - ✔✔Diagram showing evolutionary relationships among species
✔✔Node - ✔✔Point on a phylogenetic tree representing a common ancestor
✔✔Clade - ✔✔Group consisting of an ancestor and all its descendants
✔✔Most recent common ancestor - ✔✔The most recent individual shared by two
lineages
✔✔Endosymbiont theory - ✔✔Theory that mitochondria and chloroplasts evolved from
bacteria
✔✔Evidence for endosymbiosis - ✔✔Own DNA, double membranes, bacterial size,
independent replication
✔✔Protein - ✔✔Functional molecule made of one or more polypeptides
✔✔Polypeptide - ✔✔Chain of amino acids encoded by a gene
✔✔Amino acid - ✔✔Building block of proteins
✔✔Primary protein structure - ✔✔Linear sequence of amino acids
✔✔Secondary protein structure - ✔✔Alpha helices and beta sheets formed by hydrogen
bonding
✔✔Tertiary protein structure - ✔✔Overall 3D shape formed by side-chain interactions
✔✔Quaternary protein structure - ✔✔Protein structure formed from multiple polypeptide
subunits
✔✔Peptide bond - ✔✔Covalent bond linking amino acids together
✔✔R group - ✔✔Side chain of an amino acid that determines its chemical properties
✔✔Nonpolar side chains - ✔✔Hydrophobic amino acids typically found inside proteins
, ✔✔Polar or charged side chains - ✔✔Hydrophilic amino acids typically found on protein
surfaces
✔✔DNA - ✔✔Double-stranded nucleic acid storing genetic information
✔✔Nucleotide - ✔✔Building block of DNA or RNA
✔✔Complementary base pairing - ✔✔A pairs with T; G pairs with C
✔✔Chargaff's rules - ✔✔Amounts of A=T and G=C in DNA
✔✔Semiconservative replication - ✔✔Each new DNA molecule contains one old strand
and one new strand
✔✔RNA - ✔✔Single-stranded nucleic acid involved in gene expression
✔✔mRNA - ✔✔RNA that carries genetic instructions from DNA to ribosome
✔✔tRNA - ✔✔RNA that brings amino acids to the ribosome during translation
✔✔Central dogma - ✔✔Flow of genetic information from DNA to RNA to protein
✔✔Transcription - ✔✔Process of making RNA from a DNA template
✔✔Translation - ✔✔Process of building a protein from an mRNA sequence
✔✔Gene regulation - ✔✔Control of when and how much a gene is expressed
✔✔Operon - ✔✔Prokaryotic gene regulation system with coordinated gene control
✔✔Promoter - ✔✔DNA sequence where RNA polymerase binds
✔✔Operator - ✔✔DNA site where repressors bind in operons
✔✔Repressor - ✔✔Protein that blocks transcription
✔✔Activator - ✔✔Protein that increases transcription
✔✔Enhancer - ✔✔DNA region that increases transcription in eukaryotes
✔✔Genome - ✔✔Complete set of genetic material in an organism
✔✔Gene - ✔✔Segment of DNA that encodes a functional product
