Mitochondria: Structure, Function, and Role in Cellular Respiration

Question 1

Which recent technological advancement has significantly enhanced our understanding of mitochondrial biology?

Accepted Answer

Cryo-electron microscopy

Answer

Flow cytometry

Answer

Animal modeling

Answer

Electrophysiology

Question 2

Which molecule serves as the final electron acceptor in the process of cellular respiration?

Accepted Answer

Oxygen

Answer

NAD+

Answer

FADH2

Answer

Cytochrome c

Question 3

What is the primary role of the mitochondrial matrix in cellular function?

Accepted Answer

To house the ribosomes and mitochondrial DNA

Answer

To facilitate protein import and folding

Answer

To regulate mitochondrial membrane potential

Answer

To buffer calcium ions

Question 4

Which of the following diseases is associated with mutations in mitochondrial DNA?

Accepted Answer

Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS)

Answer

Cystic fibrosis

Answer

Huntington's disease

Answer

Down syndrome

Question 5

How do mitochondria contribute to the regulation of cellular calcium homeostasis?

Accepted Answer

By buffering calcium ions in the mitochondrial matrix

Answer

By transporting calcium ions into the cytosol

Answer

By releasing calcium ions from the endoplasmic reticulum

Answer

By inhibiting calcium channels on the plasma membrane

Question 6

Which technique is commonly used to isolate and purify mitochondria from cells for research purposes?

Accepted Answer

Differential centrifugation

Answer

Fluorescence-activated cell sorting (FACS)

Answer

Polymerase chain reaction (PCR)

Answer

Immunoblotting

Question 7

What is the dual nature of reactive oxygen species (ROS) in mitochondrial function?

Accepted Answer

ROS are harmful byproducts that can damage mitochondrial components, but also act as signaling molecules at low concentrations

Answer

ROS are essential substrates for ATP synthesis

Answer

ROS are inhibitors of mitochondrial calcium uptake

Answer

ROS are exclusively harmful to mitochondrial function

Question 8

Which of the following is NOT a function of mitochondria?

Accepted Answer

Protein synthesis

Answer

Cellular respiration

Answer

Synthesis of ATP

Answer

Ion regulation

Question 9

What is the inner membrane of the mitochondria highly folded to form?

Accepted Answer

Cristae

Answer

Mitochondrial matrix

Answer

Intermembrane space

Answer

Outer membrane

Question 10

Which enzyme complex is responsible for the final step of oxidative phosphorylation?

Accepted Answer

Complex IV

Answer

Complex I

Answer

Complex II

Answer

Complex V

Question 11

What is the main component of the mitochondrial matrix?

Accepted Answer

Proteins

Answer

Water

Answer

Phospholipids

Answer

Nucleic acids

Question 12

What is the process by which mitochondria divide?

Accepted Answer

Budding

Answer

Binary fission

Answer

Fragmentation

Answer

Fusion

Question 13

What is the name of the mitochondrial protein involved in apoptosis?

Accepted Answer

Cytochrome c

Answer

Bcl-2

Answer

Caspase-9

Answer

Apoptosis-inducing factor

Question 14

What is the major role of the outer mitochondrial membrane?

Accepted Answer

Transport of molecules into and out of the mitochondria

Answer

Generation of ATP

Answer

Electron transport

Answer

Protein synthesis

Question 15

What is the primary function of mitochondria within eukaryotic cells?

Accepted Answer

Generation of cellular energy through respiration

Answer

Synthesis of proteins

Answer

Detoxification and waste management

Answer

Storage of lipids

Question 16

Which structures within mitochondria are responsible for its highly folded inner membrane?

Accepted Answer

Cristae

Answer

Matrix

Answer

Intermembrane space

Answer

Outer membrane

Question 17

Identify the component of the mitochondrial electron transport chain responsible for transferring electrons to oxygen:

Accepted Answer

Cytochrome c oxidase

Answer

ATP synthase

Answer

Ribosomes

Answer

Glycogen

Question 18

Where within the mitochondrion does the process of oxidative phosphorylation occur?

Accepted Answer

Inner mitochondrial membrane

Answer

Matrix

Answer

Intermembrane space

Answer

Outer mitochondrial membrane

Question 19

Which technique is commonly employed to visualize and study mitochondrial structure and function?

Accepted Answer

Electron microscopy

Answer

Flow cytometry

Answer

Western blotting

Answer

Immunohistochemistry

Question 20

The nickname 'powerhouses of the cell' is attributed to mitochondria primarily due to their role in:

Accepted Answer

ATP production

Answer

Protein synthesis

Answer

Waste disposal

Answer

DNA replication

Question 21

Mitochondrial DNA exhibits a unique structural characteristic, which is:

Accepted Answer

Circular

Answer

Double-stranded

Answer

Single-stranded

Answer

Linear

Question 22

Mitochondrial diseases are predominantly inherited from the:

Accepted Answer

Mother

Answer

Father

Answer

Both parents

Answer

Neither parent