Topic 3: The Cell + Principle Parts of the Cell (cell membrane) Flashcards
In general, what is a cell and what can it do?
- basic structural and functional unit of the body
- can perform all basic life functions
Name the principle parts of a cell
- plasma membrane
- cytoplasm
The cell membrane is made of a ____ ____.
phospholipid bilayer
What are the characteristics of a phospholipid bilayer? (2)
- phosphate head group (hydrophilic)
- FA tails (hydrophobic)
What does the phospholipid bilayer do?
separates the ICF (inside cell) from the ECF (outside cell)
Name the components of the cell membrane (5)
- phospholipid bilayer
- cholesterol
- membrane proteins (Integral and peripheral)
- membrane carbohydrates
- microvilli
Where is cholesterol in the plasma membrane, and what is its function there?
- scattered throughout the membrane
- adds stability to the membrane
What are the two types of membrane proteins?
- integral and peripheral
Where are integral proteins in the membrane? (2)
- within the membrane
- some extend across entire membrane = transmembrane
Are integral proteins hydrophobic or hydrophilic?
hydrophobic
Where are peripheral proteins in the membrane?
- attached to extracellular or intracellular region of integral proteins
- ie. on the periphery of the cell membrane
What are the functions of membrane proteins?
- enzymes
- transporters
- channels (ex. aquaporins)
- receptors
- anchors
- identity markers (for the immune system)
Where are membrane carbohydrates found? (2)
- only on outer surface
- bound to proteins (glycoproteins) or lipids (glycolipids)
What are the functions of membrane carbohydrates? (2)
- cell recognition ie. how sperm recognizes an egg cell
- anchors cells together
What are microvilli? (2)
- small projections of the cell membrane to increase surface area (for absorption, secretion, etc.)
- best seen on cells of the small intestine and kidney
