BIO 351
BIO 351 - Exam 1 Fall 2025 Questions With
Correct Detailed Answers
1. Signaling between endosteal osteoblasts and hematopoietic stem cells (HSCs) in the bone marrow
niche are necessary for which of the following?
A) Maintenance of HSC potency and proliferation
B) Angioblast specification
C) Differentiation of myeloid cells only
D) Lymphoid cell differentiation only - ANSWER ✔ - A) Maintenance of HSC potency and proliferation
2. You have made a trans gene expressing a LacZ reporter gene. Where will this trans gene integrate into
the genome?
A) At the LacZ locus
B) It will not integrate into the genome
C) A random chromosomal location
D) On a plasmid - ANSWER ✔ - C) A random chromosomal location
3. You are able to fluorescently label cells in the ectoderm of a chick embryo (1) and watch the embryo
over the course of a few days. You notice that the labeled cells (1) now have developed into cells shaped
like (2), (3), and (4). What best describes the process you have observed?
A) differentiation
B) commitment
C) determination
D) specification - ANSWER ✔ - A) differentiation
1|P a g e
, BIO 351
4. Which of the following properties of ES cells make them useful for making knock out mutations?
A) They are omnipotent and cannot be cultured.
B) They are pluripotent, will self-renew, and will integrate vector DNA by homologous recombination.
C) They can only become cells of the germ line.
D) They are monopotent, can't self-renew, and can be injected into another blastocyst. - ANSWER ✔ - B)
They are pluripotent, will self-renew, and will integrate vector DNA by homologous recombination.
5. Which of the following is the correct order of developmental steps leading to a specialized cell type?
A) determination, differentiation, specification
B) specification, determination, differentiation
C) differentiation, specification, determination
D) determination, specification, differentiation
E) differentiation, determination, specification - ANSWER ✔ - B) specification, determination,
differentiation
6. The diagram below shows an example of juxtacrine signaling. Cell-cell contact is mediated through the
__________ ligand on the inducing cell and _________ receptor on the responding cell in this pathway.
Fill in the blanks.
A) Repressor, CSL
B) P300, CSL
C) Notch, Delta
D) Protease, Notch
E) Delta, Notch - ANSWER ✔ - E) Delta, Notch
7. Which of the following techniques would be most appropriate for directly studying the secretion of
WNT1 and its distribution through the extracellular space of the embryonic spinal cord?
A) Immunohistochemistry
2|P a g e
BIO 351 - Exam 1 Fall 2025 Questions With
Correct Detailed Answers
1. Signaling between endosteal osteoblasts and hematopoietic stem cells (HSCs) in the bone marrow
niche are necessary for which of the following?
A) Maintenance of HSC potency and proliferation
B) Angioblast specification
C) Differentiation of myeloid cells only
D) Lymphoid cell differentiation only - ANSWER ✔ - A) Maintenance of HSC potency and proliferation
2. You have made a trans gene expressing a LacZ reporter gene. Where will this trans gene integrate into
the genome?
A) At the LacZ locus
B) It will not integrate into the genome
C) A random chromosomal location
D) On a plasmid - ANSWER ✔ - C) A random chromosomal location
3. You are able to fluorescently label cells in the ectoderm of a chick embryo (1) and watch the embryo
over the course of a few days. You notice that the labeled cells (1) now have developed into cells shaped
like (2), (3), and (4). What best describes the process you have observed?
A) differentiation
B) commitment
C) determination
D) specification - ANSWER ✔ - A) differentiation
1|P a g e
, BIO 351
4. Which of the following properties of ES cells make them useful for making knock out mutations?
A) They are omnipotent and cannot be cultured.
B) They are pluripotent, will self-renew, and will integrate vector DNA by homologous recombination.
C) They can only become cells of the germ line.
D) They are monopotent, can't self-renew, and can be injected into another blastocyst. - ANSWER ✔ - B)
They are pluripotent, will self-renew, and will integrate vector DNA by homologous recombination.
5. Which of the following is the correct order of developmental steps leading to a specialized cell type?
A) determination, differentiation, specification
B) specification, determination, differentiation
C) differentiation, specification, determination
D) determination, specification, differentiation
E) differentiation, determination, specification - ANSWER ✔ - B) specification, determination,
differentiation
6. The diagram below shows an example of juxtacrine signaling. Cell-cell contact is mediated through the
__________ ligand on the inducing cell and _________ receptor on the responding cell in this pathway.
Fill in the blanks.
A) Repressor, CSL
B) P300, CSL
C) Notch, Delta
D) Protease, Notch
E) Delta, Notch - ANSWER ✔ - E) Delta, Notch
7. Which of the following techniques would be most appropriate for directly studying the secretion of
WNT1 and its distribution through the extracellular space of the embryonic spinal cord?
A) Immunohistochemistry
2|P a g e
