Endoplasmic Reticulum Functions and Structure

The video explains the role of the endoplasmic reticulum (ER) in eukaryotic cells, highlighting its function in making and packaging proteins and lipids. It describes the two types of ER: rough ER, which has ribosomes and is involved in protein assembly, and smooth ER, which is responsible for lipid packaging. The video also covers the endomembrane system, which includes the nuclear envelope, ER, Golgi body, and vesicles, all crucial for protein and lipid transport within and outside the cell.

What is the primary function of the endoplasmic reticulum in eukaryotic cells?

• To generate energy for the cell

• To make and package proteins and lipids

• To transport oxygen

• To store genetic information

In skeletal muscle cells, what does the endoplasmic reticulum store?

• Sodium ions

• Calcium ions

• Potassium ions

• Chloride ions

What distinguishes the rough endoplasmic reticulum from the smooth endoplasmic reticulum?

• Presence of ribosomes

• Ability to store calcium

• Connection to the Golgi body

• Production of ATP

What is the main role of the smooth endoplasmic reticulum?

• Protein synthesis

• Lipid assembly and packaging

• Photosynthesis

• DNA replication

How does the rough endoplasmic reticulum contribute to protein synthesis?

• By breaking down proteins

• By embedding ribosomes that produce proteins

• By transporting proteins to the mitochondria

• By storing proteins

Which of the following is NOT part of the endomembrane system?

• Mitochondria

• Nuclear envelope

• Vesicles

• Golgi body

What is the function of the endomembrane system?

• To store genetic material

• To assemble, modify, and transport proteins and lipids

• To generate cellular energy

• To facilitate cell division

What connects the endoplasmic reticulum to the nuclear envelope?

• Plasma membrane

• Cytoskeleton

• Endomembrane system

• Cell wall