Question 1

Which of the following best describes the difference between totipotent and pluripotent stem cells?

Accepted Answer

Totipotent cells can differentiate into any tissue, including placenta, while pluripotent cells can differentiate into any tissue except placenta.

Question 2

During meiosis, what is the chromosome number change from the original diploid cell to the resulting gametes?

Accepted Answer

From $$2n to$$ $$n$$

Question 3

Which process is used in animal cloning to create a genetically identical organism?

Accepted Answer

Somatic cell nuclear transfer (SCNT)

Question 4

What is the main ethical controversy surrounding the use of embryonic stem cells (ESCs) from IVF embryos?

Accepted Answer

The destruction of embryos that could potentially develop into humans

Question 5

Which of the following genes is NOT commonly used to reprogram adult fibroblasts into induced pluripotent stem cells (iPSCs)?

Accepted Answer

LGR5

Question 6

In the tetraploid complementation assay, what is the role of the tetraploid embryo?

Accepted Answer

It forms the trophoblast but cannot generate the inner cell mass (ICM)

Question 7

Why are clones produced by SCNT not exact replicas of the nuclear DNA donor?

Accepted Answer

Because mitochondrial DNA is inherited from the egg cell donor

Question 8

Which of the following best describes the potency of adult hematopoietic stem cells (HSCs)?

Accepted Answer

Multipotent

Question 9

What is the primary advantage of therapeutic cloning over traditional transplantation?

Accepted Answer

It eliminates transplant rejection by producing patient-specific embryonic stem cells

Question 10

Which of the following is a limitation of reproductive cloning in mammals, as demonstrated by the cloning of Dolly the sheep?

Accepted Answer

Low efficiency, with many embryos failing to develop or survive

Question 11

Which step in fertilization prevents polyspermy (the entry of multiple sperm into the egg)?

Accepted Answer

Release of cortical granules and fusion of plasma membranes

Question 12

Which of the following best explains why pluripotent stem cells are used to generate organoids for disease research?

Accepted Answer

They can differentiate into multiple cell types, mimicking organ architecture and function

Question 13

Which of the following is a real-world application of induced pluripotent stem cells (iPSCs)?

Accepted Answer

Repairing disease-causing mutations using gene targeting and in vitro differentiation

Question 14

Which equation correctly represents the chromosome number after meiosis in gametes?

Accepted Answer

$$n = \frac{2n}{2}$$

Question 15

What is the main function of the genes Oct4, Sox2, and Nanog in stem cells?

Accepted Answer

Activate genes for self-renewal and pluripotency, and repress genes that induce differentiation

Question 16

Which of the following is a challenge for therapeutic cloning in humans?

Accepted Answer

Not enough human eggs are available to treat all patients

Question 17

Which of the following statements about the blastocyst stage is correct?

Accepted Answer

The inner cell mass is pluripotent and can develop into any cell of the fetus but not placental cells

Question 18

Which of the following is a real-world example of stem cell niche maintenance?

Accepted Answer

LGR5+ intestinal stem cells residing in crypts to generate all cell types of the intestinal epithelium

Question 19

Which of the following is a key reason why pluripotent stem cell lines are established from multiple embryos?

Accepted Answer

Genetic diversity allows for research on different disease models and therapies

Stem Cells and Cloning: Principles, Methods, and Applications

Study Guide - Practice Questions