BIOL 133 EXAM 3 | COMPREHENSIVE BIOLOGY STUDY GUIDE, PRACTICE
QUESTIONS & ANSWERS 2026/2027
gene expression - ANS ✔✔the process by which information from a gene is used in the synthesis of a
functional gene product that enables it to produce end products, protein or non-coding RNA, and
ultimately affect a phenotype, as the final effect.
protein synthesis - ANS ✔✔the process by which amino acids are linearly arranged into proteins through
the involvement of ribosomal RNA, transfer RNA, messenger RNA, and various enzymes.
Central Dogma - ANS ✔✔DNA -> RNA -> Protein
Transcription- Translation
initiation of transcription - ANS ✔✔RNA polymerase binds to a promoter start (start!)
elongation of transcription - ANS ✔✔RNA polymerase unzips the DNA and assembles RNA nucleotides
using one strand of DNA as a template.
elongation of termination - ANS ✔✔When nonsense codon is reached, translation is terminated
Ribosome is separated into its subunits
RNA processing of primary transcript to BLANK - ANS ✔✔mRNA (mature RNA)
genetic code - ANS ✔✔collection of codons of mRNA, each of which directs the incorporation of a
particular amino acid into a protein during protein synthesis
How many codons are there? - ANS ✔✔64
How many amino acids are there? - ANS ✔✔20
Genetic code is BLANK BLANK AND BLANK - ANS ✔✔Universal, redundant, unambiguous
redundant codons - ANS ✔✔More than one codon codes for a specific amino acid.
Unambiguous property of the genetic code - ANS ✔✔one codon never codes for more than one amino
acid
Activation and repression gene transcription - ANS ✔✔activator and repressor proteins bind to control
elements of genes to activate or repress the RNA polymerase
Enhancers and transcription factors - ANS ✔✔bind activators and bend the DNA to loop back to
promotor
protein functions - ANS ✔✔enzymes, structural, receptors, transporters, regulatory.... MANY
, Types of regulation of gene expression (HOMEOSTASIS CHANGES) - ANS ✔✔Developmental (establish
fetal body and differentiation of tissue w germ cells that have RNA),
Physiological (changes in diet, hormones, and other functions homeostasis),
environmental (temp, radiation, toxins)
hemoglobin heterotetramers are composed of BLANK AND BLANK and are BLANK - ANS ✔✔2 a and 2B
global isoforms are differentially expressed due to form-stage specific hemoglobin heterotetramers
(HEME also)
what enhancer controls gene expression and on what gene region? - ANS ✔✔locas control region (LCR)
that loop back like enhancers to interact w promotors
B globin gene cluster
fetal hemoglobin - ANS ✔✔alpha and gamma
has a higher affinity for oxygen than adult hemoglobin
adult hemoglobin - ANS ✔✔alpha and beta
less oxygen then fetal
BCL11A - ANS ✔✔A transcriptional repressor that inhibits FETAL GLOBIN gene expression and results In
persistence of fetal hemoglobin in the adult stage
miRNAS negatively regulate gene expresión by BLANK - ANS ✔✔inhibiting mRNA translation
______________ are parts of __________ molecules that do not contain information about a protein's
primary structure. - ANS ✔✔introns
pre-mRNA
What does glucagon stimulate? - ANS ✔✔glucagon stimulates the liver to release glucose during fasting
by activating the transcription of specific genes. After eating, insulin blocks the release of glucose
Which characteristic of the genetic code lowers the likelihood of a mutation causing a mutant
phenotype? - ANS ✔✔redundancy
Which of the following mutations would likely be most dangerous to a cell? - ANS ✔✔deletion of one
nucleotide
Deletion of one nucleotide would shift the reading frame, altering the coding for all subsequent amino
acids. In most cases, this would destroy the function of the protein produced from this gene.
The CODING strand of a DNA molecule that encodes an mRNA molecule: - ANS ✔✔has the same
nucelotide sequence as the mRNA molecule (with Ts instead of Us).
Tetracycline is an antibiotic that kills bacteria by blocking the A-binding site on the bacterial ribosome.
This kills the bacterium by inhibiting - ANS ✔✔translation
Epigenetic changes alter the base sequence of a DNA molecule. - ANS ✔✔false
QUESTIONS & ANSWERS 2026/2027
gene expression - ANS ✔✔the process by which information from a gene is used in the synthesis of a
functional gene product that enables it to produce end products, protein or non-coding RNA, and
ultimately affect a phenotype, as the final effect.
protein synthesis - ANS ✔✔the process by which amino acids are linearly arranged into proteins through
the involvement of ribosomal RNA, transfer RNA, messenger RNA, and various enzymes.
Central Dogma - ANS ✔✔DNA -> RNA -> Protein
Transcription- Translation
initiation of transcription - ANS ✔✔RNA polymerase binds to a promoter start (start!)
elongation of transcription - ANS ✔✔RNA polymerase unzips the DNA and assembles RNA nucleotides
using one strand of DNA as a template.
elongation of termination - ANS ✔✔When nonsense codon is reached, translation is terminated
Ribosome is separated into its subunits
RNA processing of primary transcript to BLANK - ANS ✔✔mRNA (mature RNA)
genetic code - ANS ✔✔collection of codons of mRNA, each of which directs the incorporation of a
particular amino acid into a protein during protein synthesis
How many codons are there? - ANS ✔✔64
How many amino acids are there? - ANS ✔✔20
Genetic code is BLANK BLANK AND BLANK - ANS ✔✔Universal, redundant, unambiguous
redundant codons - ANS ✔✔More than one codon codes for a specific amino acid.
Unambiguous property of the genetic code - ANS ✔✔one codon never codes for more than one amino
acid
Activation and repression gene transcription - ANS ✔✔activator and repressor proteins bind to control
elements of genes to activate or repress the RNA polymerase
Enhancers and transcription factors - ANS ✔✔bind activators and bend the DNA to loop back to
promotor
protein functions - ANS ✔✔enzymes, structural, receptors, transporters, regulatory.... MANY
, Types of regulation of gene expression (HOMEOSTASIS CHANGES) - ANS ✔✔Developmental (establish
fetal body and differentiation of tissue w germ cells that have RNA),
Physiological (changes in diet, hormones, and other functions homeostasis),
environmental (temp, radiation, toxins)
hemoglobin heterotetramers are composed of BLANK AND BLANK and are BLANK - ANS ✔✔2 a and 2B
global isoforms are differentially expressed due to form-stage specific hemoglobin heterotetramers
(HEME also)
what enhancer controls gene expression and on what gene region? - ANS ✔✔locas control region (LCR)
that loop back like enhancers to interact w promotors
B globin gene cluster
fetal hemoglobin - ANS ✔✔alpha and gamma
has a higher affinity for oxygen than adult hemoglobin
adult hemoglobin - ANS ✔✔alpha and beta
less oxygen then fetal
BCL11A - ANS ✔✔A transcriptional repressor that inhibits FETAL GLOBIN gene expression and results In
persistence of fetal hemoglobin in the adult stage
miRNAS negatively regulate gene expresión by BLANK - ANS ✔✔inhibiting mRNA translation
______________ are parts of __________ molecules that do not contain information about a protein's
primary structure. - ANS ✔✔introns
pre-mRNA
What does glucagon stimulate? - ANS ✔✔glucagon stimulates the liver to release glucose during fasting
by activating the transcription of specific genes. After eating, insulin blocks the release of glucose
Which characteristic of the genetic code lowers the likelihood of a mutation causing a mutant
phenotype? - ANS ✔✔redundancy
Which of the following mutations would likely be most dangerous to a cell? - ANS ✔✔deletion of one
nucleotide
Deletion of one nucleotide would shift the reading frame, altering the coding for all subsequent amino
acids. In most cases, this would destroy the function of the protein produced from this gene.
The CODING strand of a DNA molecule that encodes an mRNA molecule: - ANS ✔✔has the same
nucelotide sequence as the mRNA molecule (with Ts instead of Us).
Tetracycline is an antibiotic that kills bacteria by blocking the A-binding site on the bacterial ribosome.
This kills the bacterium by inhibiting - ANS ✔✔translation
Epigenetic changes alter the base sequence of a DNA molecule. - ANS ✔✔false
