NCERT Class 9 Science — Chapter 1: The fundamental unit of life

mcqmedium

The process known as "Membrane Biogenesis" involves:

Official previous-year question

Verified 1 Aug 2026.

Options

AThe building of the cell membrane using proteins and lipids synthesized by the ER.
BThe formation of the nuclear membrane during cell division.
CThe synthesis of cell wall cellulose by plastids.
DThe breakdown of the plasma membrane during endocytosis.

Did you get this right?

Solution

The correct option is

The building of the cell membrane using proteins and lipids synthesized by the ER.

Explanation

Membrane Biogenesis is the biological process through which the cell membrane is synthesized and renewed. This process relies heavily on the manufacturing capabilities of the endomembrane system, specifically the Endoplasmic Reticulum (ER).

Detailed Analysis

Synthesis of Components: The plasma membrane is primarily composed of lipids and proteins.
- The Smooth Endoplasmic Reticulum (SER) is responsible for the manufacture of fat molecules, or lipids, important for cell function.
- The Rough Endoplasmic Reticulum (RER), which contains ribosomes, is responsible for the synthesis of proteins.
Formation Process: Some of these lipids and proteins are transported to the cell surface to build, repair, or maintain the plasma membrane. This specific process of building the cell membrane using ER-synthesized components is known as membrane biogenesis.
Incorrect Options:
- The formation of the nuclear membrane during cell division. refers to the reformation of the nuclear envelope during the telophase stage of cell division.
- The synthesis of cell wall cellulose by plastids. refers to the synthesis of the cell wall, a structure distinct from the cell membrane, found in plant cells.
- The breakdown of the plasma membrane during endocytosis. refers to the degradation or recycling of membrane components, not their synthesis (genesis).

Key Takeaway: Membrane Biogenesis is the function of the Endoplasmic Reticulum (ER) wherein it synthesizes lipids and proteins specifically to build and maintain the plasma membrane.

Your note

More from Chapter 1: The fundamental unit of life

With reference to Plastids, consider the following statements: 1. They are present only in plant cells. 2. Chromoplasts are colourless plastids, while leucoplasts contain chlorophyll. 3. Unlike mitochondria, plastids lack their own DNA and ribosomes. Which of the statements given above is/are correct?

medium

Which of the following pairs is correctly matched?

medium

Consider the following statements about Vacuoles: 1. They are small-sized in animal cells while plant cells have very large vacuoles. 2. In Amoeba, the food vacuole is absent. 3. They can play a role in expelling excess water from the cell. Which of the statements given above is/are correct?

medium

With reference to osmosis, consider the following statements: 1. Osmosis is the net diffusion of water across a selectively permeable membrane. 2. If a cell is placed in a hypotonic solution, it is likely to shrink. 3. Water molecules pass across the membrane in only one direction during osmosis. Which of the statements given above is/are correct?

medium

A plant cell is placed in a hypertonic solution. Which of the following phenomena is most likely to occur?

medium

Keep practising Chapter 1: The fundamental unit of life

Work through every question from this NCERT chapter.

Browse all NCERT Class 9 Science chapters

The correct option is

The building of the cell membrane using proteins and lipids synthesized by the ER.

Explanation

Detailed Analysis

Synthesis of Components: The plasma membrane is primarily composed of lipids and proteins.
- The Smooth Endoplasmic Reticulum (SER) is responsible for the manufacture of fat molecules, or lipids, important for cell function.
- The Rough Endoplasmic Reticulum (RER), which contains ribosomes, is responsible for the synthesis of proteins.
Formation Process: Some of these lipids and proteins are transported to the cell surface to build, repair, or maintain the plasma membrane. This specific process of building the cell membrane using ER-synthesized components is known as membrane biogenesis.
Incorrect Options:
- The formation of the nuclear membrane during cell division. refers to the reformation of the nuclear envelope during the telophase stage of cell division.
- The synthesis of cell wall cellulose by plastids. refers to the synthesis of the cell wall, a structure distinct from the cell membrane, found in plant cells.
- The breakdown of the plasma membrane during endocytosis. refers to the degradation or recycling of membrane components, not their synthesis (genesis).

Key Takeaway: Membrane Biogenesis is the function of the Endoplasmic Reticulum (ER) wherein it synthesizes lipids and proteins specifically to build and maintain the plasma membrane.