Chapter 4, Problem 1TYU

Which structure is not part of the endomembrane system?

1. A.    nuclear envelope
2. B.     chloroplast
3. C.     Golgi apparatus
4. D.    plasma membrane

Summary Introduction

Introduction:

The endomembrane system includes the Golgi apparatus, lysosomes, vacuoles, and other kinds of vesicles. This system performs various kinds of functions in the cell such as protein synthesis and transportation of proteins into membranes.

Answer to Problem 1TYU

Correct answer:

The chloroplast is not a part of the endomembrane system. Therefore, option (b) is correct.

Explanation of Solution

Reason for the correct statement:

The chloroplast is a different organelle and has two-membrane system. It is used during photosynthesis in autotrophs. The chloroplast contains the membrane called the chloroplast envelope.

Option (b) is given as “chloroplast”.

As “chloroplast is not a part of the endomembrane system”, it is the right answer.

Hence, option (b) is correct.

Reasons for the incorrect statements:

Option (a) is given as “nuclear envelop”.

A double-membrane system that separates the nucleus from the cytoplasm with perinuclear space is known as the nuclear envelope and is a part of the endomembrane system. Therefore, it is a wrong answer.

Option (c) is given as “Golgi apparatus”.

In the cytoplasm, a complex form of stacks is membrane-bound and that is known as the Golgi apparatus. The Golgi apparatus is a part of the endomembrane system. Therefore, it is a wrong answer.

Option (d) is given as “plasma membrane”.

The plasma membrane is a bilayer membrane which has two different layers. The inner layer is hydrophobic, and the outer layer is hydrophilic. The plasma membrane is a part of the endomembrane system. Therefore, it is a wrong answer.

Hence, options (a), (c) and (d) are incorrect.

Conclusion

The nuclear envelope, Golgi apparatus, and plasma membrane are the parts of the endomembrane system, but chloroplast is not a part of the endomembrane system.