Question 1

Which of the following best describes totipotency in the context of developmental genetics?

Accepted Answer

The ability of a cell to develop into any cell type, including extraembryonic tissues.

Question 2

During early embryonic development, which stage is characterized by cells that are still totipotent in mammals?

Accepted Answer

8-cell embryo stage

Question 3

Which process is responsible for the selective expression of genes during development, and is influenced by environmental factors?

Accepted Answer

Epigenetics

Question 4

A researcher wants to clone a carrot plant from a single cell. Which property of plant cells makes this possible?

Accepted Answer

Totipotency

Question 5

Which of the following statements about animal cloning is TRUE?

Accepted Answer

Cloned animals may differ in cytoplasmic genes due to mitochondrial DNA from the recipient egg.

Question 6

Which enzyme family is central to the execution of apoptosis by cleaving essential proteins and activating DNase?

Accepted Answer

Caspases

Question 7

A patient with a neurodegenerative disease is found to have excessive apoptosis in neurons. Which diseases could this mechanism contribute to?

Accepted Answer

Parkinson's and Alzheimer's

Question 8

Which developmental event in humans is a direct result of apoptosis?

Accepted Answer

Separation of digits in the hands

Question 9

What is the main difference between necrosis and apoptosis?

Accepted Answer

Apoptosis is a controlled, genetically programmed process, while necrosis is uncontrolled and often results from injury.

Question 10

Which of the following best describes the process of reprogramming differentiated adult cells into induced pluripotent stem (iPS) cells?

Accepted Answer

It requires the introduction of specific reprogramming factors to revert cells to a pluripotent state.

Question 11

Which of the following equations correctly represents the ploidy change during fertilization?

Accepted Answer

$$n + n \rightarrow 2n$$

Question 12

In the context of stem cell potency, which sequence correctly orders the cell types from most to least potent?

Accepted Answer

Totipotent \u003e Pluripotent \u003e Multipotent \u003e Monopotent

Question 13

Which of the following is NOT a potential medical application of induced pluripotent stem (iPS) cells?

Accepted Answer

Direct treatment of bacterial infections

Question 14

Why are plant cells generally more amenable to cloning than animal cells?

Accepted Answer

Plant cells remain totipotent longer, allowing them to regenerate into whole plants under suitable conditions.

Question 15

Which protein is crucial for removing mutated tumor cells by triggering apoptosis?

Accepted Answer

p53

Question 16

A scientist observes that a cloned sheep has mitochondrial DNA different from the donor nucleus. What is the most likely explanation?

Accepted Answer

Mitochondrial DNA comes from the recipient egg, not the donor nucleus.

Question 17

Which of the following is a real-world example of apoptosis in development?

Accepted Answer

Loss of tadpole’s tail during metamorphosis

Question 18

Which of the following statements about gene expression during development is correct?

Accepted Answer

Development requires selective expression of genes at the right time, amount, and location.

Question 19

Which pathway best describes the sequence of events in apoptosis?

Accepted Answer

Caspases activate DNase, DNA is degraded, cell shrinks, and is engulfed by macrophages.

Question 20

Which of the following scenarios would most likely result in necrosis rather than apoptosis?

Accepted Answer

A cell is injured by physical trauma.

Chapter 22: Developmental Genetics – Life and Death

Study Guide - Practice Questions