Developmental Bio 351 Exam 1
QUESTIONS AND VERIFIED
CORRECT ANSWER GRADED
A+ 100% GUARANTEED PASS
LATEST[2026-2027]
These genes are also important in the development of the early blastocyte stage embryo.
Endosteal niche interactions
endosteal osteoblast secretes wnt signal binds to _______. interaction is important for
__________. - CORRECT ANSWER-Frizzled; Self renewal
Endosteal niche interactions
Angiopoietin-1 is secreted by endosteal osteoblast and binds to _______. interaction is
important for ________. - CORRECT ANSWER-Receptor Tie2 (RTK); maintaining potency
Signaling between endosteal osteoblasts and hematopoietic stem cells (HSC) in the niche are
necessary for which of the following?
,A. Differentiation of myeloid cells only.
B. T and B cell differentiation
C. Maintenance of HSC potency and proliferation
D. Angioblast specification - CORRECT ANSWER-C. Maintenance of HSC potency and
proliferation
Which of the following statements is FALSE?
a.Cell fates are reversible after specification.
b.During autonomous specification, cells require communication with surrounding cells for
commitment to a particular cell fate.
c.Differentiation involves changes in gene expression, morphology, and function.
d.Cell fates are irreversible after determination. - CORRECT ANSWER-b.During autonomous
specification, cells require communication with surrounding cells for commitment to a
particular cell fate.
in situ hybridization - CORRECT ANSWER-detection of gene expression - provides temporal and
spacial info by detecting mRNA
Antisense mRNA complementary to specific mRNA
-- antisense -> binds specifically through base pair
EX: MyoD expression is detected by an antisense RNA probe.
• demonstrates spatial expression over embryonic time
• Qualitative assay
RT-PCR "reverse transcription" - CORRECT ANSWER-RNA --> making DNA
,-allows us to look at genes expressed in tissues and cells
have to destroy the cells/tissue to extract RNA from the sample.
• Quantitative RT-PCR provides measure of the expression for one gene per assay.
• Multiple assays can be run at a time, up to hundreds.
siRNA - CORRECT ANSWER-small interfering RNA
Takes advantage of the cell's microRNA (miRNA) machinery
to "silence" the expression of specific genes
• Offers a method of examining the role or function of a gene product without the need to
make a genomic mutation.
• Must be able to get the siRNA into cells, so need a delivery system.
process of siRNA - CORRECT ANSWER-siRNA enter the cell via lipid-based transfection
then separated into single strands
so they can integrate into the active RISC complex
after integrated to RISC,siRNA's pair to their target mRNA
--siRNAs base-pair to their target mRNA and induce cleavage of the mRNA, or inhibition of
translation
what is the expected result from using siRNA in a cell? - CORRECT ANSWER-reduced expression
of specific protein
more specifically After integration into the RISC, siRNAs base-pair to their target mRNA and
induce cleavage of the mRNA, or inhibition of translation
, what do you need to make a transgenic mouse - CORRECT ANSWER-1.transgene
2.fertilized oocytes
3.pseudopregnant foster mother
4.Method to screen for targeted embryos or pups
all transgenes must contain ___. - CORRECT ANSWER-promoting sequence
transcriptional start site
intron
AUG protein coding sequence
transcriptional stop sequence
STOP codon and 3' polyA site
homologous recombination - CORRECT ANSWER-recomination in which two nucleotide
sequences are exchanged between two similar or identical molecules of dna
nonhomologous recombination - CORRECT ANSWER-dan can reintegrated via end joining at
double strand breaks
Requires linear dsDNA with free ends.
TRANSGENES
What can you learn from a transgenic mouse? - CORRECT ANSWER-1.Where are tissue or cell
specific enhancer sites.
2.When during embryonic time an enhancer/ promoter is functional.
3.What does a specific cell lineage become.
4.Where do cells of a specific lineage migrate. Role of specific genes in development.
QUESTIONS AND VERIFIED
CORRECT ANSWER GRADED
A+ 100% GUARANTEED PASS
LATEST[2026-2027]
These genes are also important in the development of the early blastocyte stage embryo.
Endosteal niche interactions
endosteal osteoblast secretes wnt signal binds to _______. interaction is important for
__________. - CORRECT ANSWER-Frizzled; Self renewal
Endosteal niche interactions
Angiopoietin-1 is secreted by endosteal osteoblast and binds to _______. interaction is
important for ________. - CORRECT ANSWER-Receptor Tie2 (RTK); maintaining potency
Signaling between endosteal osteoblasts and hematopoietic stem cells (HSC) in the niche are
necessary for which of the following?
,A. Differentiation of myeloid cells only.
B. T and B cell differentiation
C. Maintenance of HSC potency and proliferation
D. Angioblast specification - CORRECT ANSWER-C. Maintenance of HSC potency and
proliferation
Which of the following statements is FALSE?
a.Cell fates are reversible after specification.
b.During autonomous specification, cells require communication with surrounding cells for
commitment to a particular cell fate.
c.Differentiation involves changes in gene expression, morphology, and function.
d.Cell fates are irreversible after determination. - CORRECT ANSWER-b.During autonomous
specification, cells require communication with surrounding cells for commitment to a
particular cell fate.
in situ hybridization - CORRECT ANSWER-detection of gene expression - provides temporal and
spacial info by detecting mRNA
Antisense mRNA complementary to specific mRNA
-- antisense -> binds specifically through base pair
EX: MyoD expression is detected by an antisense RNA probe.
• demonstrates spatial expression over embryonic time
• Qualitative assay
RT-PCR "reverse transcription" - CORRECT ANSWER-RNA --> making DNA
,-allows us to look at genes expressed in tissues and cells
have to destroy the cells/tissue to extract RNA from the sample.
• Quantitative RT-PCR provides measure of the expression for one gene per assay.
• Multiple assays can be run at a time, up to hundreds.
siRNA - CORRECT ANSWER-small interfering RNA
Takes advantage of the cell's microRNA (miRNA) machinery
to "silence" the expression of specific genes
• Offers a method of examining the role or function of a gene product without the need to
make a genomic mutation.
• Must be able to get the siRNA into cells, so need a delivery system.
process of siRNA - CORRECT ANSWER-siRNA enter the cell via lipid-based transfection
then separated into single strands
so they can integrate into the active RISC complex
after integrated to RISC,siRNA's pair to their target mRNA
--siRNAs base-pair to their target mRNA and induce cleavage of the mRNA, or inhibition of
translation
what is the expected result from using siRNA in a cell? - CORRECT ANSWER-reduced expression
of specific protein
more specifically After integration into the RISC, siRNAs base-pair to their target mRNA and
induce cleavage of the mRNA, or inhibition of translation
, what do you need to make a transgenic mouse - CORRECT ANSWER-1.transgene
2.fertilized oocytes
3.pseudopregnant foster mother
4.Method to screen for targeted embryos or pups
all transgenes must contain ___. - CORRECT ANSWER-promoting sequence
transcriptional start site
intron
AUG protein coding sequence
transcriptional stop sequence
STOP codon and 3' polyA site
homologous recombination - CORRECT ANSWER-recomination in which two nucleotide
sequences are exchanged between two similar or identical molecules of dna
nonhomologous recombination - CORRECT ANSWER-dan can reintegrated via end joining at
double strand breaks
Requires linear dsDNA with free ends.
TRANSGENES
What can you learn from a transgenic mouse? - CORRECT ANSWER-1.Where are tissue or cell
specific enhancer sites.
2.When during embryonic time an enhancer/ promoter is functional.
3.What does a specific cell lineage become.
4.Where do cells of a specific lineage migrate. Role of specific genes in development.
