Ch. 3: Cell physiology Flashcards
(38 cards)
How are cells found
In different shapes and sizes
1 billion cells per kilogram of tissue(2 billion per lbs)
10% of all cells in the body are replaced every minute
Components within cells and cell function changes as a result of aging, disease, and exercise
What type of cells have a high turnover and which cells have low turnover
Skin cells
Cardiac and skeletal muscle cells/fibers
What is an example of a cell changing shape
When a patient has a heart attack the cardiac cells die and cannot be replaced
What is example of cell death in skeletal muscle
Skeletal muscle fibers die and cannot be healed to normal or full function
Changes in structure and function of a cell within an organ will ultimately ______________________
influence the function of the whole body
All changes affect your cells
What are the four common components of the cell
Plasma membrane
Cytoplasm
Organelles-little organs
Nucleus
What are four compositions of plasma membrane
Lipids - phospholipids (most common)
proteins - integral proteins and peripheral (extracellular) proteins
cholesterol - components of plasma membrane found in lipid Bilayer
glycolipids and glycoproteins- sugarcoated
What is the fluid Mosaic model
Representation of the lipid bilayer of the plasma membrane
Proteins float and move with the_________ __________
Integral proteins span the entire__________ ___________
Plasma membrane
Lipid Bilayer
What are phospholipids
They had two components consisting of a phosphate head and a fatty acid tail
Head-polar in hydrophilic (water loving) outside the layer
Tail-nonpolar hydrophobic (does not like water) inside the layer
What are fluid compartments
Chemicals in the extracellular and intracellular fluid can be classified on a solubility continuum
What is an example of water soluble and lipid soluble?
Water soluble: glucose, sodium (Na+) and potassium (K+)
Lipid Soluble: O2, CO2, cortisol (stress hormone)
What is the functional significance of lipid bilayer
Plasma membrane is a selectively in permeable barrier
Hydrophobic area:
-restricts the passage of water soluble molecules (lipids, oils and water don’t mix)
-allows for lipid Soluble molecules and gases to diffuse across membrane
What are two different type of membrane proteins and describe them
Integral proteins-span the width of the membrane
Peripheral proteins - are on the innercellular and extracellular surfaces (inner and outer surface of plasma membrane)
What are the functions of integral membrane proteins and what are some examples
Channels: passage of water-soluble molecules in water
Carrier proteins: transport of water-soluble molecules
Receptors: allow for water-soluble molecules to communicate with the cell
Adhesion molecules: “docking structures” for cells to adhere to and to communicate with each other ex. (cell to cell adhesion to form tissue)
Integral proteins that are channels are ___________
Bidirectional
Come in or out of the cell both directions
Water can enter in the cell through the channel in the can also leave through the channel
Ex.) door opening and closing
Ex.) Na+ channel and K+ channel
Diffusion goes from an area of ______ concentration to an area of _______ solute concentration
High to low
Integral membrane proteins such as channels that do not use extracellular fluid only occur in the
Cardiac muscle
Communication between cells without using extracellular fluid is called
Connexon
Integral proteins carrier is
Locking key affect very specific to which molecule can be transported
The door is not continuously open, it is like a revolving door
This carrier is specific to glucose only
Bidirestional
Integral membrane receptor
Secretory cell uses a hormone or chemical messenger to binds to the receptor of the target cell
-this is the docking say for various water-soluble molecules locking key method Also applies
Integral proteins with adhesion molecules
Example are cadherin proteins
Peripheral membrane proteins consists of
Extracellular surface and intracellular surface
What components make up the extracellular surface
Enzymes which are biological catalysts
adhesion molecules
receptors or foreign antigens