Membrane bound organelles are also referred to as ...

A) vesicles
B) channels
C) integral proteins
D) a and b

To determine the correct answer, let's break down each option and understand its meaning in the context of cell biology.

A) Vesicles: Vesicles are small, membrane-bound sacs that transport various molecules within the cell. While some organelles, such as endosomes or transport vesicles, are considered vesicles, it is not a generic term for all membrane-bound organelles.

B) Channels: Channels are proteins embedded within the cell membrane that allow the passage of specific ions or molecules across the membrane. They serve as a means of transportation but do not fully encompass the concept of membrane-bound organelles.

C) Integral proteins: Integral proteins are a type of membrane protein that is permanently attached to the cell membrane. While these proteins are essential for cellular function, they do not represent membrane-bound organelles.

D) A and B: This option implies that membrane-bound organelles are either vesicles or channels. However, this is an incorrect statement because membrane-bound organelles refer to distinct structures within cells that are enclosed by membranes.

Therefore, the correct answer is none of the options provided. Membrane-bound organelles are not synonymous with vesicles, channels, or integral proteins. Some examples of membrane-bound organelles include the nucleus, mitochondria, endoplasmic reticulum (ER), Golgi apparatus, lysosomes, peroxisomes, and vacuoles.