LIFE SCIENCE

Detailed explanation-1: -The endoplasmic reticulum (ER) is a network of membrane-enclosed tubules and sacs (cisternae) that extends from the nuclear membrane throughout the cytoplasm (Figure 9.1). The entire endoplasmic reticulum is enclosed by a continuous membrane and is the largest organelle of most eukaryotic cells.

Detailed explanation-2: -Final Answer: Ribosomes are attached to the endoplasmic reticulum through a glycoprotein known as Ribophorin I and II. A larger subunit of ribosomes gets attached to the endoplasmic reticulum.

Detailed explanation-3: -The ER membrane is continuous with the outer membrane of the nuclear envelope. Portions of the sheetlike areas of the ER are studded with ribosomes, giving rise to rough ER.

Detailed explanation-4: -The endoplasmic reticulum (ER) is a membranous organelle that shares part of its membrane with that of the nucleus. Some portions of the ER, known as the rough ER, are studded with ribosomes and are involved with protein manufacture.

Detailed explanation-5: -Proteins are assembled at organelles called ribosomes. When proteins are destined to be part of the cell membrane or exported from the cell, the ribosomes assembling them attach to the endoplasmic reticulum, giving it a rough appearance.