Bio Midterm 3 Study Guide
Practice Exam: Old_exam_questions_for_2020_PoB_1_with_options.pdf
Answers: Old_exam_questions_for_2020_PoB_1_with_key.pdf
QUIZLET FOLDER: https://quizlet.com/Nikol244/folders/midterm-3?x=1xqt&i=aj20u
Lecture 18- Stem Cells
QUIZLET: https://quizlet.com/_aqd66d?x=1jqt&i=aj20u
Define what a stem cell is
● Stem cell- a relatively unspecialized cell that can make a copy of itself and at least one
other cell type
Identify embryonic versus adult stem cells
● Embryonic stem cells- stem cells that can generate all embryonic cell types, pluripotent
● Adult stem cells- stem cells that can generate a limited number of cell types, multipotent
Adult stem cells
● Are found in tissues after development
● Used to replace tissue after injury
● Committed to a specific tissue/organ
● Patterns of stem cell differentiation
○
, ●
Understand adult stem cell functions
● Adult stem cells are used to replace non reproducing cells as needed
● Used to balance cell death or cell removal to maintain equilibrium
Embryonic stem cells
● Undifferentiated cells derived from a preimplantation embryo that are capable of dividing
without differentiating for a prolonged period in culture
● known to develop into cells and tissues of the three primary germ layers.
● Reproduce indefinitely in cultures, can be made to differentiate into a variety of
specialized cells
● Taken from the inner cell mass
● Cannot differentiate into extraembryonic tissues, such as the placenta
Recognize potency differences across cells
● Stem cell potency- the ability of a particular stem cell to generate different types of
differentiated cells
○ Totipotent- a cell that can differentiate into all cells (ex: zygote)
○ Pluripotent- a cell that can differentiate into most cell types (ex: ES cells)
○ Multipotent- a cell that can differentiate into multiple specialized cell types (ex:
adult stem cells)
○ Unipotent- a cell that can differentiate into one cell type (ex: skin cell)
● The more advanced a cell, the smaller the potency
Cloning
● Plants can be cloned using one cell of the plant
● Nuclear transplantation(somatic nuclear cell transfer):
, ●
○ Remove the nucleus of an egg to create an enucleated egg and replace it with
the nucleus of a differentiated cell
○ Found that the older the donor nucleus, the lower the percentage of normal
tadpoles
○ Conclusion of the experiment:
■ most changes to the genome during development are reversible
■ There is something in the egg that resets the adult nucleus and allows it
to start development again
● Cloning mammals
○ Uses the same nuclear transfer principle established in frogs
○ Dolly the Sheep
■ A lamb cloned from an adult sheep by nuclear transfer from a
differentiated mammary gland cell
Know how pluripotent stem cell origin
● Pluripotent stem cells are derived from the inner cell mass
● Cells in the inner cell mass can differentiate into the cells and tissues of the three
primary germ layers
Induced pluripotent stem cells
● Induced pluripotent stem (iPS)- differentiated cells that are returned to their
undifferentiated state and become pluripotent
● iPS cells can perform most of the functions of ES cells.
● iPS cells can be used as models for the study of certain diseases and potentially as
replacement cells for patients.
, ●
○ Researchers used a retroviral cloning vector to introduce the 4 genes for the 4
transcription factors (Oct 4, Nanog, Sox2, and C-Myc)
○ Skin cell was transformed into an iPS cell
● To label embryonic stem cells, researchers replaced the Oct 4 gene and replaced it with
a gene for GFP, if the cell turned green, then the transcription factor was active
Poll/Lecture Questions:
● Adult stem cells are: Committed to a specific tissue/organ
● What would happen (short term) if all adult stem cells divide, and all daughter cells will
differentiate? The tissue/organ will grow
● What would happen to the long-term regenerative capacity of the tissue if adult stem
cells divide, and all daughter cells will differentiate? Tissue loses stem cells
● Would it be possible to have patient-specific embryonic stem cells? No
● Nuclear transfer (skin cell and egg): would this work for humans? No
● Oct4 is transcribed in the inner cell mass: Which cells will be green (contain green
fluorescent protein)? Embryonic stem cells, cells similar to embryonic stem cells,
the inner cell mass
Lecture 19- Immune System
QUIZLET: https://quizlet.com/_aqdmzs?x=1qqt&i=aj20u
Differentiate innate versus adaptive immunity
Practice Exam: Old_exam_questions_for_2020_PoB_1_with_options.pdf
Answers: Old_exam_questions_for_2020_PoB_1_with_key.pdf
QUIZLET FOLDER: https://quizlet.com/Nikol244/folders/midterm-3?x=1xqt&i=aj20u
Lecture 18- Stem Cells
QUIZLET: https://quizlet.com/_aqd66d?x=1jqt&i=aj20u
Define what a stem cell is
● Stem cell- a relatively unspecialized cell that can make a copy of itself and at least one
other cell type
Identify embryonic versus adult stem cells
● Embryonic stem cells- stem cells that can generate all embryonic cell types, pluripotent
● Adult stem cells- stem cells that can generate a limited number of cell types, multipotent
Adult stem cells
● Are found in tissues after development
● Used to replace tissue after injury
● Committed to a specific tissue/organ
● Patterns of stem cell differentiation
○
, ●
Understand adult stem cell functions
● Adult stem cells are used to replace non reproducing cells as needed
● Used to balance cell death or cell removal to maintain equilibrium
Embryonic stem cells
● Undifferentiated cells derived from a preimplantation embryo that are capable of dividing
without differentiating for a prolonged period in culture
● known to develop into cells and tissues of the three primary germ layers.
● Reproduce indefinitely in cultures, can be made to differentiate into a variety of
specialized cells
● Taken from the inner cell mass
● Cannot differentiate into extraembryonic tissues, such as the placenta
Recognize potency differences across cells
● Stem cell potency- the ability of a particular stem cell to generate different types of
differentiated cells
○ Totipotent- a cell that can differentiate into all cells (ex: zygote)
○ Pluripotent- a cell that can differentiate into most cell types (ex: ES cells)
○ Multipotent- a cell that can differentiate into multiple specialized cell types (ex:
adult stem cells)
○ Unipotent- a cell that can differentiate into one cell type (ex: skin cell)
● The more advanced a cell, the smaller the potency
Cloning
● Plants can be cloned using one cell of the plant
● Nuclear transplantation(somatic nuclear cell transfer):
, ●
○ Remove the nucleus of an egg to create an enucleated egg and replace it with
the nucleus of a differentiated cell
○ Found that the older the donor nucleus, the lower the percentage of normal
tadpoles
○ Conclusion of the experiment:
■ most changes to the genome during development are reversible
■ There is something in the egg that resets the adult nucleus and allows it
to start development again
● Cloning mammals
○ Uses the same nuclear transfer principle established in frogs
○ Dolly the Sheep
■ A lamb cloned from an adult sheep by nuclear transfer from a
differentiated mammary gland cell
Know how pluripotent stem cell origin
● Pluripotent stem cells are derived from the inner cell mass
● Cells in the inner cell mass can differentiate into the cells and tissues of the three
primary germ layers
Induced pluripotent stem cells
● Induced pluripotent stem (iPS)- differentiated cells that are returned to their
undifferentiated state and become pluripotent
● iPS cells can perform most of the functions of ES cells.
● iPS cells can be used as models for the study of certain diseases and potentially as
replacement cells for patients.
, ●
○ Researchers used a retroviral cloning vector to introduce the 4 genes for the 4
transcription factors (Oct 4, Nanog, Sox2, and C-Myc)
○ Skin cell was transformed into an iPS cell
● To label embryonic stem cells, researchers replaced the Oct 4 gene and replaced it with
a gene for GFP, if the cell turned green, then the transcription factor was active
Poll/Lecture Questions:
● Adult stem cells are: Committed to a specific tissue/organ
● What would happen (short term) if all adult stem cells divide, and all daughter cells will
differentiate? The tissue/organ will grow
● What would happen to the long-term regenerative capacity of the tissue if adult stem
cells divide, and all daughter cells will differentiate? Tissue loses stem cells
● Would it be possible to have patient-specific embryonic stem cells? No
● Nuclear transfer (skin cell and egg): would this work for humans? No
● Oct4 is transcribed in the inner cell mass: Which cells will be green (contain green
fluorescent protein)? Embryonic stem cells, cells similar to embryonic stem cells,
the inner cell mass
Lecture 19- Immune System
QUIZLET: https://quizlet.com/_aqdmzs?x=1qqt&i=aj20u
Differentiate innate versus adaptive immunity
