The structural and functional unit of life
Cell
What are the common structures of all cells?
Plasma membrane, cytoplasm, and nucleus
The control center of the cell
Nucleus
This is a lipid bilayer that separates intracellular fluid from extracellular fluid
Plasma membrane
True or False: Interstitial fluid is extracellular fluid that surrounds cells
True.
The plasma membrane is made up of what?
Phospholipids, glycolipids and cholesterol
The phosphate heads of the plasma membrane are ________ and _________.
Polar, hydrophilic
The fatty acid tails of the plasma membrane are ________ and ________.
Nonpolar, hydrophobic
The _________ of the plasma membrane increases stability.
Cholesterol
What are the types of proteins in the plasma membranes?
Integral and peripheral
Integral proteins are _________, while peripheral proteins are ________.
Imbedded, free floating
These types of proteins in the plasma membrane function as transport proteins (channels and carriers), enzymes, or receptors
Integral proteins
These types of proteins in the plasma membrane function as enzymes, motor proteins for shape change during cell division and muscle contraction; cell-to-cell connections
Peripheral proteins
List the functions of plasma membrane proteins
Transport, receptors for signal transduction, attachment to cytoskeleton and extracellular matrix, enzyme activity, intercellular joining, and cell-to-cell recognition
This makes up 20% of the outer membrane surface
Lipid rafts
Lipid rafts contain:
Phospholipids, sphingolipids, and cholesterol
What is the "sugar covering" at the cell surface?
Glycolax
This is what allows the immune system to recognize self from non-self, but cancerous cells change it continuously
Glycolax
Cell junctions can be ______ (like blood cells and sperm cells), or ______.
Free, bound into communities
What are the ways that cells are bound in communities?
Tight junctions, desmosomes, gap junctions.
In what type of junction do adjacent proteins fuse to form an impermeable junction encircling the cell?
Tight junctions
What type of junction has rivets or spot-welds that anchor cells together at plaques (thickenings on the plasma membrane)?
Desmosomes
In what type of junction to transmembrane proteins form pores (connexons) that allow small molecules to pass from cell to cell?
Gap junctions
Where might you find gap junctions?
For spread of ions, simple sugars, and other small molecules between cardiac or smooth muscle cells
This surrounds the cell and contains amino acids, sugars, fatty acids, vitamins, hormones, salts, waste product and water
Interstitial fluid
Plasma membranes are _______ _________.
Selectively permeable
What are the ways in which substances cross the plasma membrane?
Passive processes and active processes
In this type of process, no ATP is required and substances move down the concentration gradient.
Passive
In this type of process, ATP is required and it occurs only in living cell membranes
Active
What are the types of passive transport?
Diffusion, filtration
What are the types of diffusion?
Simple, carrier and channel-mediated, and osmosis
This type of passive transport usually occurs across capillary walls
Filtration
During diffusion, collisions cause molecules to move down or with their ________ __________.
Concentration gradient
The speed of diffusion is influenced by __________ and ___________
Molecule size and temperature.
Molecules will passively diffuse through the membrane if they are _______ soluble.
Lipid
Molecules will passively diffuse through the membrane if they are small enough or assisted by _________ __________.
Carrier molecules
Which vitamins are water soluble?
Vitamins B and C
Which vitamins are fat soluble
All other vitamins besides B and C
Which lipophobic molecules require facilitated diffusion?
Glucose, amino acids, and ions
During this type of facilitated diffusion, integral proteins assist and the binding of substrate causes shape change and then passage across the membrane.
Carrier-mediated diffusion
During this type of facilitated diffusion, aqueous channels are formed by transmembrane proteins and selectively transport ions or water.
Channel-mediated diffusion
These types of channels are always open.
Leaky
These types of channels are controlled by chemical or electrical signals
Gated
This type of passive process involves the movement of solvent across a selectively permeable membrane
Osmosis
What is the measure of the total concentration of solute particles?
Osmolarity
What is the back pressure of water on the membrane?
Hydrostatic pressure
What is the tendency of water to move into cell by osmosis?
Osmotic pressure
What is the ability of a solution to alter the cell's water volume?
Tonicity
When a solution has the same amount of non-penetrating solute concentration as the cytosol (same amount inside and outside), it is called?
Isotonic
When the solution has a higher non-penetrating solute concentration than cytosol (more solute outside), it is?
Hypertonic
When the solution has a lower non-penetrating solute concentration than cytosol (more inside than out), it is ?
Hypotonic
If there is more solute in the cell than outside the cell, water will move _______ the cell.
Into
If there is more solute outside the cell than in the cell, water will move _______ the cell
Out of