membran plasma

What is the primary function of the plasma membrane?

• To store genetic information

• To provide structural support to the cell

• The primary function of the plasma membrane is to regulate the movement of substances in and out of the cell.

• To facilitate protein synthesis

Describe the basic structure of the plasma membrane.

• A single layer of lipids with no proteins

• A rigid structure made of cellulose

• The plasma membrane consists of a phospholipid bilayer with embedded proteins and cholesterol, forming a semi-permeable barrier.

• A network of carbohydrates and nucleic acids

What are phospholipids and how do they arrange in the plasma membrane?

• Phospholipids are molecules with hydrophilic heads and hydrophobic tails that arrange in a bilayer in the plasma membrane.

• Phospholipids have hydrophobic heads and hydrophilic tails that form a single layer.

• Phospholipids are proteins that help in cell signaling.

• Phospholipids are only found in the nucleus of cells.

Explain the role of proteins in the plasma membrane.

• Proteins in the plasma membrane are primarily responsible for energy production.

• Proteins in the plasma membrane play roles in signaling, transport, structural support, and cell recognition.

• Proteins in the plasma membrane only serve as a barrier to protect the cell.

• Proteins in the plasma membrane are involved in DNA replication.

What is the fluid mosaic model of the plasma membrane?

• The fluid mosaic model of the plasma membrane is a dynamic structure composed of a lipid bilayer with embedded proteins, allowing for flexibility and functionality.

• A simple lipid layer with no embedded components.

• A static layer of proteins without any lipids.

• A rigid structure made entirely of carbohydrates.

How do cholesterol molecules affect the plasma membrane?

• Cholesterol decreases membrane stability and fluidity.

• Cholesterol forms channels for ion transport in the membrane.

• Cholesterol stabilizes membrane fluidity and contributes to lipid raft formation.

• Cholesterol acts as a barrier preventing all substances from entering the cell.

What is the significance of membrane permeability?

• Membrane permeability is solely responsible for cell division.

• Membrane permeability has no effect on cellular communication.

• Membrane permeability is only important for energy production.

• Membrane permeability is significant for regulating the movement of substances, maintaining homeostasis, and supporting cellular functions.

Describe the difference between integral and peripheral proteins.

• Peripheral proteins are embedded within the lipid bilayer.

• Integral proteins are only found in the cytoplasm.

• Integral proteins can easily detach from the membrane surface.

• Integral proteins are embedded in the membrane, while peripheral proteins are attached to the membrane surface.

How do carbohydrates contribute to the function of the plasma membrane?

• Carbohydrates act as a barrier to prevent all substances from entering the cell.

• Carbohydrates are the primary energy source for the cell membrane.

• Carbohydrates provide structural support to the plasma membrane.

• Carbohydrates contribute to cell recognition, signaling, and adhesion in the plasma membrane.

What role do glycoproteins play in cell recognition?

• Glycoproteins serve as structural components of the cell membrane.

• Glycoproteins act as cell surface markers for recognition and communication between cells.

• Glycoproteins are involved in energy production within cells.

• Glycoproteins are primarily responsible for DNA replication.