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Which of the following are functions of the plasma membrane?

The principal components of the plasma membrane are lipids ( phospholipids and cholesterol), proteins, and carbohydrates. The plasma membrane protects intracellular components from the extracellular environment. The plasma membrane mediates cellular processes by regulating the materials that enter and exit the cell.

Which of the following is not a membrane is organelle?

Ribosomes are the translational apparatus of the cell with two major components the small ribosomal subunit which reads the RNA, and the large subunit which joins amino acids to form a polypeptide chain. Each subunit is composed of one or more rRNA molecules and a variety of proteins. It is devoid of any membrane.

What is not a membranous organelle?

Non-membranous organelles are not surrounded by a plasma membrane. Most non-membranous organelles are part of the cytoskeleton, the major support structure of the cell. These include: filaments, microtubules, and centrioles. Overview of the main cellular components and tissues.

What is the function of cholesterol in the plasma membrane?

Cholesterol modulates the bilayer structure of biological membranes in multiple ways. It changes the fluidity, thickness, compressibility, water penetration and intrinsic curvature of lipid bilayers.

What are two functions of proteins in the cell membrane?

For example, plasma membrane proteins carry out functions as diverse as ferrying nutrients across the plasma membrane, receiving chemical signals from outside the cell, translating chemical signals into intracellular action, and sometimes anchoring the cell in a particular location (Figure 4).

Where is the Nucleoid found?

The nucleoid region is the irregularly-shaped section of a prokaryotic cell where DNA is housed. It lacks the membrane that is found around the nucleus of eukaryotic cells. In addition to DNA, the nucleoid may also contain RNA, proteins, and enzymes that can be used for cellular processes.

What happens if the Nucleoid is missing?

If the nucleus didn’t exist, the cell wouldn’t have direction and the nucleolus, which is inside the nucleus, wouldn’t be able to produce ribosomes. If the cell membrane were gone, the cell would be uprotected. Everything would lead to the death of the cell.

Do all bacteria have Nucleoid?

Unlike the eukaryotic (true) cells, bacteria do not have a membrane enclosed nucleus. The chromosome, a single, continuous strand of DNA, is localized, but not contained, in a region of the cell called the nucleoid. All the other cellular components are scattered throughout the cytoplasm.