Podcast Beta
Questions and Answers
What is the primary characteristic of the lipid bilayer in the fluid mosaic model?
Which type of membrane protein directly passes through the hydrophobic interior of the lipid bilayer?
How does cholesterol affect membrane fluidity at low temperatures?
What role do carbohydrates play in the cell membrane?
Signup and view all the answers
What prevents the destruction of the membrane when temperatures exceed the optimum level?
Signup and view all the answers
Which of the following is NOT a function of membrane proteins?
Signup and view all the answers
What type of fatty acids contributes to the fluidity of the membrane?
Signup and view all the answers
What is the polar part of a phospholipid that interacts with water called?
Signup and view all the answers
Study Notes
The Fluid Mosaic Model
- Proposed by S. Jonathan Singer and Garth Nicolson in 1972.
- Describes the arrangement and movement of lipids and proteins in the cell membrane.
- Lipids are hydrophobic due to their hydrocarbon composition.
- Phospholipid molecules have a hydrophilic phosphate head and hydrophobic fatty acid tails.
- Phospholipid bilayer: heads face outward toward water, tails face inward away from water.
Fatty Acids
- Unsaturated fatty acids contain double bonds, creating kinks.
- Saturated fatty acids consist of single bonds and have a linear structure.
- Cholesterol helps maintain membrane fluidity by occupying kinks of unsaturated fatty acids, especially during temperature fluctuations.
Membrane Proteins
- Integral Membrane Proteins: Span the bilayer, interacting with both hydrophilic and hydrophobic regions.
- Peripheral Membrane Proteins: Positioned on the membrane surface and do not penetrate the bilayer.
Functions of Membrane Proteins
- Signal transmission between cells.
- Enzymatic activity to facilitate biochemical reactions.
- Cell-to-cell recognition for immune response and tissue formation.
- Attachment to cells and other molecules for structural support.
- Transport functions to move substances across the membrane.
Carbohydrates in Membranes
- Serve as sources of energy, including sugars, starch, and glycogen.
- Found in the cell membrane as components of glycoproteins, where carbohydrates are attached to proteins for cell recognition and signaling.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on the Fluid Mosaic Model, a crucial concept in cell biology introduced by S. Jonathan Singer and Garth Nicolson in 1972. This model explains the structure and function of the cell membrane. Dive into the details of membrane properties and their biological significance.
