Ch 16-2 Flashcards
What is cloning
Process by which new organism is formed which has exact same genetic composition to the parent
What are the 2 types of cloning
Organismal and cell cloning
What was the significance of F.C. Steward’s experiment in the 1950s?
He successfully cloned a carrot, proving that differentiation does not cause irreversible change to the cell’s DNA
What is nuclear transplantation?
Removing the nucleus of an egg cell and replacing it with the nucleus of a differentiated cell.
What was the first successful reproductive mammal clone?
Dolly the sheep, born in 1997
What are stem cells?
Can divide and make copies of themselves [self renew] or change into other types of cells [differentiation]
Have the ability to turn into diff type of cells [muscle, brain, skin cells] for growth, repair, healing but replacing damaged or lost cells
What are induced-pluripotent stem (iPS) cells?
Differentiated cells that have been “reprogrammed” back into embryonic stem cells.
Taking adult cells and reprogramming them to turn into many different type of cells
Pluripotent meaning
Cells ability to become any type of cell in body
Oncogenes meaning
A form of a gene which when expressed leads to the development of cancer.
What are tumor-suppressor genes?
Genes that inhibit cell division, preventing uncontrolled cell growth.
What are the two types of tumors?
Benign (non-cancerous) and malignant (cancerous).
T / f
Cloning can only be performed in animals.
False. Cloning can also be performed in plants.
T/ f
Dolly the sheep was the first organism ever cloned.
False. Plants were cloned before Dolly, and nuclear transplantation experiments had been conducted in animals.
T/f
All cells in an adult organism are differentiated.
False. Adult organisms also contain stem cells, which are undifferentiated.
T/ f
Induced pluripotent stem cells (iPS cells) are derived from embryonic stem cells.
False. iPS cells are created by “reprogramming” differentiated cells back into an embryonic-like state.
T /f
Cancer is always caused by a single mutation.
F
Multiple mutations
T / f
Oncogenes promote cell growth and division
T [but uncontollably]
T / f
Tumor suppressor genes are mutated forms of proto-oncogenes.
False.
. Proto-oncogenes promote cell growth, while tumor suppressor genes inhibit it.
T /f
All tumors are cancerous.
False. Benign tumors are not cancerous, while malignant tumors are.
T / f
Viruses cannot cause cancer.
False. Viruses can cause cancer by interfering with gene regulation.
T /f
Cancer is only caused by genetic factors.
False. Cancer is a complex disease that can be influenced by genetic factors, environmental factors, and infections.
Cloned organisms may exhibit defects due to the epigenetic modifications present in the transferred ___ nucleus.
Differentiated
___ the process by which cells become specialized in structure and function.
Differentiation
___ genes whose expression can lead to the development of cancer.
Oncogene
The products of __ genes inhibit cell division, helping to prevent uncontrolled cell growth
Tumor suppressor
___ cells are unspecialized cells with the potential to reproduce indefinitely and differentiate into various specialized cell types
Stem
Which of the following is NOT a type of cloning?
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a) Organismal cloning
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b) Cell cloning
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c) Gene cloning
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d) Reproductive cloning
C
What did F.C. Steward’s experiment with carrots demonstrate?
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a) Differentiated cells lose genes during development.
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b) Differentiation causes irreversible changes to DNA.
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c) Differentiation does not cause irreversible changes to DNA.
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d) All cells are totipotent.
C
What type of cell was used as the donor nucleus to clone Dolly the sheep?
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a) Skin cell
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b) Mammary cell
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c) Egg cell
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d) Embryonic stem cell
B
From what developmental stage are embryonic stem cells typically harvested?
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a) Bone marrow
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b) Blood
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c) Blastocyst
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d) Skin
C
What significant ethical concern has been raised regarding the use of embryonic stem cells?
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a) They are difficult to harvest.
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b) They are derived from human embryos.
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c) They have a high risk of rejection.
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d) They are not very effective.
B
Which of the following is NOT a characteristic of cancer cells?
○
a) Uncontrolled growth
○
b) Invasion of surrounding tissues
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c) Differentiation
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d) Metastasis
C
Oncogenes are derived from:
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a) Tumor suppressor genes
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b) Proto-oncogenes
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c) Viral genomes
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d) All of the above
B
Which of the following is an example of a tumor suppressor gene?
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a) p53
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b) Ras
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c) Myc
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d) HER2
A
Which term describes a tumor that is not cancerous?
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a) Malignant
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b) Benign
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c) Metastatic
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d) Invasive
B
Approximately what percentage of human cancers are thought to be associated with viruses?
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a) 5%
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b) 15%
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c) 25%
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d) 50%
B
