PUBH 6011 Final Examination And All
Correct Answers 2025\2026 Edition.
Understand the major function of cells - Answer Cell differentiation: in bone marrow, adult
stem cell can reproduce and splits to either myeloid or lymphoid progenitor, which can then
differentiate into many kinds of cells
Homeostasis and cell injury: many adverse biological effects occur when cells are damaged,
damage can be to any part of the cell, causes can be infectious agents, oxygen deprivation,
trauma, chemicals, nutritional imbalances
Apoptosis vs. Necrosis - Answer Apoptosis- programmed cell death, active, orderly and
organized; requires energy a plan and enzymatic degradation of proteins/dna; produces neatly
packed cell fragments that are recycled
Necrosis- cell damage and death, passive and disorderly; produces cell debris
Bacteria vs Virus - Answer bacteria
-prokaryotic cell
-most are free living
-relatively large
-antibiotics used to kill
Virus
-not a living cell (genes packaged in protein shell)
-intracellular parasite
-1/1000 size of a bacteria
-vaccine used to prevent
-antiviral treatment
protein synthesis - Answer the formation of proteins by using information contained in DNA
and carried by mRNA
,Role of mRNA in protein synthesis (transcription) - Answer single stranded messenger that
carries the genetic information copied from DNA in the form of a series of a three base code of
words.
Role of tRNA in protein synthesis (translation) - Answer is the key to diciphering the code
words from mRNA
Role of ribosomes in protein synthesis - Answer ribosomes are complexes made of ribosomal
RNA and protein
ribosomes carry out protein synthesis in two locations
a minute particle consisting of RNA and associated proteins found in large numbers in the
cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides
and proteins.
Explain how biological and genetic factors can influence our response to environmental hazards
- Answer mutagens- pollutants in the environment that can enter the body and directly
change your DNA sequence (ex. the chemicals in cigarette smoke can cause cancer)
Gene-gene interactions: ○ occur when pollutants in the environment do not change your DNA
sequence, but rather cause a chain reaction that affects the functioning of one gene that then
affects the functioning of another gene
■ Ex. Regularly drinking way too much alcohol can cause the gene TACE not to produce enough
of its protein. TACE protein is supposed to help the MTHFR gene make enough of its protein.
Too little MTHRF protein changes the level of folate in our blood, and low folate levels may
cause depression.
○ Transcription factors - pollutants in the environment can indirectly affect the DNA sequence
by altering transcription factors, which are responsible for starting the process of using genes to
make proteins that are needed for different functions in the body
■ Ex. stress can change the amount of proteins made by genes involved in your immune system
and therefore, you may get sick more easily when you're stressed
○ Epigenetics - the environment can alter your health by affecting the proteins that turns genes
on or off
■ Half the genes that cause familial or inherited cancer are turned off when pollutants in the
environment affect these proteins. Because they are turned off, these genes cannot suppress
tumor formation or repair DNA
, - Chronic disease have been associated with the human microbiota
Antibiotics can disrupt microbiota
The bacteria in the microbiome help digest our food, regulate our immune system, protect
against other bacteria that cause disease, and produce vitamins including B vitamins B12,
thiamine and riboflavin, and Vitamin K, which is needed for blood coagulation.
Epigenetics - Answer the study of environmental influences on gene expression that occur
without a DNA change
DNA methylation - Answer The addition of methyl groups to bases of DNA after DNA synthesis;
may serve as a long-term control of gene expression.
histone modification - Answer adding chemical modifications to proteins called histones that
are involved in packaging DNA
micro-RNA (miRNA) - Answer A small, single-stranded RNA molecule that binds to a
complementary sequence in mRNA molecules and directs associated proteins to degrade or
prevent translation of the target mRNA.
Microlesions - Answer change in 1 bp
substitution
point mutation (silent, nonsense, missense)
frameshift mutations
Macrolesions - Answer chromosome aberrations
- Often caused by effects on mitotic machinery, not DNA
- Change in chromosome structure
- Deletion, duplication, inversion, translocation—may be stable
- Acentric fragments, dicentric chromosomes—usually cell death
Correct Answers 2025\2026 Edition.
Understand the major function of cells - Answer Cell differentiation: in bone marrow, adult
stem cell can reproduce and splits to either myeloid or lymphoid progenitor, which can then
differentiate into many kinds of cells
Homeostasis and cell injury: many adverse biological effects occur when cells are damaged,
damage can be to any part of the cell, causes can be infectious agents, oxygen deprivation,
trauma, chemicals, nutritional imbalances
Apoptosis vs. Necrosis - Answer Apoptosis- programmed cell death, active, orderly and
organized; requires energy a plan and enzymatic degradation of proteins/dna; produces neatly
packed cell fragments that are recycled
Necrosis- cell damage and death, passive and disorderly; produces cell debris
Bacteria vs Virus - Answer bacteria
-prokaryotic cell
-most are free living
-relatively large
-antibiotics used to kill
Virus
-not a living cell (genes packaged in protein shell)
-intracellular parasite
-1/1000 size of a bacteria
-vaccine used to prevent
-antiviral treatment
protein synthesis - Answer the formation of proteins by using information contained in DNA
and carried by mRNA
,Role of mRNA in protein synthesis (transcription) - Answer single stranded messenger that
carries the genetic information copied from DNA in the form of a series of a three base code of
words.
Role of tRNA in protein synthesis (translation) - Answer is the key to diciphering the code
words from mRNA
Role of ribosomes in protein synthesis - Answer ribosomes are complexes made of ribosomal
RNA and protein
ribosomes carry out protein synthesis in two locations
a minute particle consisting of RNA and associated proteins found in large numbers in the
cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides
and proteins.
Explain how biological and genetic factors can influence our response to environmental hazards
- Answer mutagens- pollutants in the environment that can enter the body and directly
change your DNA sequence (ex. the chemicals in cigarette smoke can cause cancer)
Gene-gene interactions: ○ occur when pollutants in the environment do not change your DNA
sequence, but rather cause a chain reaction that affects the functioning of one gene that then
affects the functioning of another gene
■ Ex. Regularly drinking way too much alcohol can cause the gene TACE not to produce enough
of its protein. TACE protein is supposed to help the MTHFR gene make enough of its protein.
Too little MTHRF protein changes the level of folate in our blood, and low folate levels may
cause depression.
○ Transcription factors - pollutants in the environment can indirectly affect the DNA sequence
by altering transcription factors, which are responsible for starting the process of using genes to
make proteins that are needed for different functions in the body
■ Ex. stress can change the amount of proteins made by genes involved in your immune system
and therefore, you may get sick more easily when you're stressed
○ Epigenetics - the environment can alter your health by affecting the proteins that turns genes
on or off
■ Half the genes that cause familial or inherited cancer are turned off when pollutants in the
environment affect these proteins. Because they are turned off, these genes cannot suppress
tumor formation or repair DNA
, - Chronic disease have been associated with the human microbiota
Antibiotics can disrupt microbiota
The bacteria in the microbiome help digest our food, regulate our immune system, protect
against other bacteria that cause disease, and produce vitamins including B vitamins B12,
thiamine and riboflavin, and Vitamin K, which is needed for blood coagulation.
Epigenetics - Answer the study of environmental influences on gene expression that occur
without a DNA change
DNA methylation - Answer The addition of methyl groups to bases of DNA after DNA synthesis;
may serve as a long-term control of gene expression.
histone modification - Answer adding chemical modifications to proteins called histones that
are involved in packaging DNA
micro-RNA (miRNA) - Answer A small, single-stranded RNA molecule that binds to a
complementary sequence in mRNA molecules and directs associated proteins to degrade or
prevent translation of the target mRNA.
Microlesions - Answer change in 1 bp
substitution
point mutation (silent, nonsense, missense)
frameshift mutations
Macrolesions - Answer chromosome aberrations
- Often caused by effects on mitotic machinery, not DNA
- Change in chromosome structure
- Deletion, duplication, inversion, translocation—may be stable
- Acentric fragments, dicentric chromosomes—usually cell death
