Module 9 Flashcards
What are cell membranes composed of?
Two layers of lipids
Cell membranes primarily consist of phospholipids that form a bilayer.
What type of lipid mainly makes up cell membranes?
Phospholipids
Phospholipids are essential for forming the bilayer structure of cell membranes.
What regions do phospholipids have?
Hydrophilic and hydrophobic regions
These regions contribute to the unique properties of phospholipids in membrane formation.
What structures do phospholipids form in an aqueous environment?
Micelles and bilayers
Phospholipids spontaneously arrange into these structures due to their hydrophilic and hydrophobic properties.
Are cell membranes static or dynamic?
Dynamic
This fluid nature allows for movement and flexibility within the membrane.
What does it mean that membranes are fluid?
They can change and adapt their structure
Membrane fluidity is crucial for various cellular processes.
What regions do phospholipids have?
Phospholipids have both hydrophilic and hydrophobic regions.
This dual nature is essential for their role in cell membranes.
What structures do phospholipids spontaneously form in an aqueous environment?
Phospholipids spontaneously form structures such as micelles and bilayers.
These structures are crucial for the formation of cell membranes.
What is a key characteristic of cell membranes?
Cell membranes are dynamic.
This dynamism allows for various cellular processes and interactions.
What does it mean that membranes are fluid?
Membrane macromolecules are able to move laterally in the plane of the membrane.
This fluidity is important for membrane function and integrity.
What factors influence membrane fluidity?
The length of fatty acid chains, the presence of carbon-carbon double bonds in fatty acid chains, and the amount of cholesterol.
These factors determine how fluid or rigid the membrane is, impacting its functionality.
What components do many membranes contain?
Proteins and lipids.
This combination is crucial for the structure and function of the membrane.
What are transmembrane proteins?
Proteins that span the membrane.
They play essential roles in transporting substances across the membrane.
What are peripheral proteins?
Proteins that are temporarily associated with one or the other layer of the lipid bilayer.
They are not embedded in the membrane but interact with its surfaces.
What functions can proteins embedded in the cell membrane perform?
Transporters, receptors, enzymes, or anchors.
These functions are vital for cell communication and transport.
What does the fluid mosaic model of cell membranes state?
Membranes are dynamic and made up of several components, including lipids, proteins, and carbohydrates.
This model emphasizes the flexibility and variety of the membrane structure.
