Question

the figure above shows an organelle typically found in eukaryotic cells. which of the following best describes the function of the double membrane system of this organelle?
a the outer membrane allows the transport of all molecules into the intermembrane space, while the inner membrane serves as the regulatory boundary.
b the inner membrane has specialized proteins that create a hydrogen ion concentration gradient between the intermembrane space and the matrix.
c the outer membrane contains transport proteins that establish a sodium ion concentration gradient used for atp production, while the inner membrane contains transport proteins that establish a hydrogen ion concentration gradient used for glucose production.
d the toxins and wastes entering a cell cross the outer membrane and are detoxified by digestive enzymes stored within the intermembrane space.

Explanation:

This question is about the function of the mitochondria's double - membrane system. The mitochondria is the powerhouse of the cell. The inner membrane is crucial for ATP production. It has proteins (such as ATP synthase and those involved in the electron - transport chain) that create a hydrogen ion ($H^+$) concentration gradient. This gradient is used in chemiosmosis to synthesize ATP.

• Option A: The outer membrane is semi - permeable (not allowing all molecules to pass). Small molecules like oxygen, carbon dioxide, and water can pass through, but larger molecules cannot. So, this option is incorrect.
• Option B: The inner membrane has proteins (e.g., in the electron - transport chain) that pump hydrogen ions from the matrix to the intermembrane space, creating a hydrogen ion concentration gradient. This is correct as this gradient is essential for ATP synthesis via chemiosmosis.
• Option C: The outer membrane does not establish a sodium ion gradient for ATP production. Also, glucose is not produced in the mitochondria (glucose is broken down in the mitochondria). Glucose production (gluconeogenesis) occurs in the cytoplasm and sometimes in the endoplasmic reticulum. So, this option is incorrect.
• Option D: The intermembrane space does not store digestive enzymes for detoxifying toxins and wastes. Lysosomes are the organelles mainly responsible for detoxification and waste removal. So, this option is incorrect.

Answer:

B. The inner membrane has specialized proteins that create a hydrogen ion concentration gradient between the intermembrane space and the matrix.