Cell Surface Membrane Flashcards
What is the primary function of the cell surface membrane?
To regulate the movement of substances in and out of the cell.
True or False: The cell surface membrane is impermeable to all substances.
False.
Fill in the blank: The cell surface membrane is composed mainly of __________ and proteins.
phospholipids
What structure forms the bilayer in the cell surface membrane?
Phospholipids.
What is the term for the model that describes the structure of the cell surface membrane?
Fluid mosaic model.
Multiple Choice: Which of the following is NOT a component of the cell surface membrane? A) Cholesterol B) RNA C) Proteins D) Phospholipids
B) RNA.
What role do proteins play in the cell surface membrane?
They serve as channels, receptors, and enzymes.
True or False: Cholesterol helps to stabilize the fluidity of the cell membrane.
True.
What is the significance of glycoproteins in the cell surface membrane?
They play a key role in cell recognition and signaling.
Fill in the blank: The movement of water across the cell membrane is known as __________.
osmosis
What type of transport requires energy to move substances across the cell membrane?
Active transport.
Multiple Choice: Which of the following is an example of passive transport? A) Endocytosis B) Exocytosis C) Diffusion D) Sodium-potassium pump
C) Diffusion.
What is the term for the process by which cells engulf large particles?
Phagocytosis.
True or False: The cell surface membrane is static and does not change.
False.
What is the role of membrane-bound enzymes?
To catalyze reactions at the cell surface.
Fill in the blank: __________ are specialized proteins that act as receptors for signaling molecules.
Receptor proteins
What is the effect of temperature on the fluidity of the cell membrane?
Higher temperatures increase fluidity, while lower temperatures decrease it.
Multiple Choice: Which component of the membrane helps to prevent fatty acid chains from packing too closely together? A) Phospholipids B) Proteins C) Cholesterol D) Carbohydrates
C) Cholesterol.
What is the term for the carbohydrate chains attached to proteins and lipids on the extracellular surface of the membrane?
Glycocalyx.
True or False: The cell surface membrane can form vesicles.
True.
What is the primary purpose of the sodium-potassium pump?
To maintain the electrochemical gradient across the membrane.
Fill in the blank: The __________ of the membrane allows it to be selectively permeable.
phospholipid bilayer
What is an example of a molecule that can easily pass through the cell membrane?
Oxygen.
Multiple Choice: Which of the following processes involves the fusion of vesicles with the plasma membrane? A) Phagocytosis B) Pinocytosis C) Exocytosis D) Facilitated diffusion
C) Exocytosis.
What is the role of aquaporins in the cell surface membrane?
To facilitate the transport of water molecules.
