DHN 311 STUDY GUIDE 2025/2026 QUESTIONS WITH
SOLUTIONS RATED A+
✔✔what are the three ways in which gene regulation's access to DNA can change -
✔✔acetylation - DNA relaxes (expressed)
de-acetylation - DNA contracts (not expressed)
methylation - DNA contracts (not expressed)
✔✔what is gene amplification - ✔✔increase in the number of copies of a gene
✔✔what are the two types of regulation that occur at the level of transcription - ✔✔1.
transcriptional regulation mediated by regulatory signals binding directly to intracellular
receptors (faster)
2. Transcriptional regulation mediated by cell-surface receptors (indirect)
✔✔Describe direct transcriptional regulation during gene regulation - ✔✔the receptors
are intracellular proteins located in the cytosol or the nucleus
these receptors respond to small hydrophobic signaling molecules that diffuse across
the plasma membrane
✔✔what type of molecules can directly bind during transcriptional regulation -
✔✔lipophilic, small molecular weight molecules such as steroid hormones (cortisol,
estrogen), vitamin A, vitamin D, or thyroid hormones
✔✔what does ligand binding do during transcriptional regulation - ✔✔have direct effects
on the receptors, repress or activate
✔✔all types of RNA's are post transcriptionally modified by - ✔✔ribonucleases
✔✔splicing - ✔✔the process of removing introns and reconnecting exons
✔✔isoforms - ✔✔closely related proteins whose function is similar but whose affinity for
ligands differs (generated by splicing)
✔✔when would gene regulation occur at the level of translation - ✔✔1. proteins
required for translation are unavailable
2. limited amino acid availability
3. accumulation of damaged proteins or peptides that hold up the process
✔✔what are two different types of gene regulation that occur co-and-post-translationally
- ✔✔1. phosphorylation - the process of adding a P group (kinases, increase or
decrease function)
2. glycosylation - adding carbs to a protein chain
, ✔✔protein folding - ✔✔the process by which a protein structure assumes its functional
shape or conformation
determined by the primary structure or facilitated by chaperone proteins
✔✔what happens to misfolded or defective proteins - ✔✔they are marked for
destruction
✔✔what happens during protein destruction - ✔✔broken down by the proteasome in the
cytosol
amino acids can be recycled
✔✔three types of nutritional genomics - ✔✔1. nutrigenetics
2. nutrigenomics
3. epigenetics
✔✔what happens during genetic variations when a nucleotide base changes -
✔✔polymorphism
✔✔what is a single nucleotide polymorphism - ✔✔a variation in a single base pair in a
DNA sequence
✔✔nurtigenics - ✔✔genetics dictate nutrition or diet
how variations in genes may increase or decrease the body needs for specific nutrients
✔✔how is PKU an example of nurtigenetics - ✔✔mutation in phenylalanine hydroxylate,
need a diet low in phenylalanine because the mutation causes you to not be able to
consume it
✔✔nutrigenomics - ✔✔diet effects gene expression
dietary components can turn genes on or off (gene expression)
✔✔Epigenetics - ✔✔the influence of environment/lifestyle (diet), age, and disease
conditions on changes in gene expression without changing the DNA sequences
there is a change in the phenotype without a change in the nucleotide sequence of DNA
or the genotype
"tag" on the gene, can turn them on or off
✔✔is epigenetic heritable - ✔✔yes
SOLUTIONS RATED A+
✔✔what are the three ways in which gene regulation's access to DNA can change -
✔✔acetylation - DNA relaxes (expressed)
de-acetylation - DNA contracts (not expressed)
methylation - DNA contracts (not expressed)
✔✔what is gene amplification - ✔✔increase in the number of copies of a gene
✔✔what are the two types of regulation that occur at the level of transcription - ✔✔1.
transcriptional regulation mediated by regulatory signals binding directly to intracellular
receptors (faster)
2. Transcriptional regulation mediated by cell-surface receptors (indirect)
✔✔Describe direct transcriptional regulation during gene regulation - ✔✔the receptors
are intracellular proteins located in the cytosol or the nucleus
these receptors respond to small hydrophobic signaling molecules that diffuse across
the plasma membrane
✔✔what type of molecules can directly bind during transcriptional regulation -
✔✔lipophilic, small molecular weight molecules such as steroid hormones (cortisol,
estrogen), vitamin A, vitamin D, or thyroid hormones
✔✔what does ligand binding do during transcriptional regulation - ✔✔have direct effects
on the receptors, repress or activate
✔✔all types of RNA's are post transcriptionally modified by - ✔✔ribonucleases
✔✔splicing - ✔✔the process of removing introns and reconnecting exons
✔✔isoforms - ✔✔closely related proteins whose function is similar but whose affinity for
ligands differs (generated by splicing)
✔✔when would gene regulation occur at the level of translation - ✔✔1. proteins
required for translation are unavailable
2. limited amino acid availability
3. accumulation of damaged proteins or peptides that hold up the process
✔✔what are two different types of gene regulation that occur co-and-post-translationally
- ✔✔1. phosphorylation - the process of adding a P group (kinases, increase or
decrease function)
2. glycosylation - adding carbs to a protein chain
, ✔✔protein folding - ✔✔the process by which a protein structure assumes its functional
shape or conformation
determined by the primary structure or facilitated by chaperone proteins
✔✔what happens to misfolded or defective proteins - ✔✔they are marked for
destruction
✔✔what happens during protein destruction - ✔✔broken down by the proteasome in the
cytosol
amino acids can be recycled
✔✔three types of nutritional genomics - ✔✔1. nutrigenetics
2. nutrigenomics
3. epigenetics
✔✔what happens during genetic variations when a nucleotide base changes -
✔✔polymorphism
✔✔what is a single nucleotide polymorphism - ✔✔a variation in a single base pair in a
DNA sequence
✔✔nurtigenics - ✔✔genetics dictate nutrition or diet
how variations in genes may increase or decrease the body needs for specific nutrients
✔✔how is PKU an example of nurtigenetics - ✔✔mutation in phenylalanine hydroxylate,
need a diet low in phenylalanine because the mutation causes you to not be able to
consume it
✔✔nutrigenomics - ✔✔diet effects gene expression
dietary components can turn genes on or off (gene expression)
✔✔Epigenetics - ✔✔the influence of environment/lifestyle (diet), age, and disease
conditions on changes in gene expression without changing the DNA sequences
there is a change in the phenotype without a change in the nucleotide sequence of DNA
or the genotype
"tag" on the gene, can turn them on or off
✔✔is epigenetic heritable - ✔✔yes
