In which part of the body is the most water found?
Plasma
Interstitial fluid
Minor components
Intracellular fluids
The four main cations in cells are
The major intracellular cation is
Na+
K+
Ca++
Mg++
The defines a cell, and acts as a continuous barrier between the inside and outside, allowing for the creation of an internal environment
Which organelles are vesicles containing enzymes for the breakdown of material?
Mitochondria
Golgi apparatus
Lysosomes
Nucleoli
What is the purpose of the rough endoplasmic reticulum (RER) being continuous with the outer nuclear membrane?
As the RER produces proteins from the instructions of the nucleus, this allows fast movement between the two organelles
To create a larger surface area to volume ratio
As the RER produces proteins from the instructions of the nucleus, this allows for the RER to create extra messages for other organelles to produce proteins
To create a larger concentration gradient for the flow of proteins
Specialised junctions called link adjacent cells without sealing them into a sheet, giving them some degree of flexibility and being able to withstand stress
The lipids of the cell membranes contain two non-polar polar( non-polar, polar ) fatty acid chains stuck together by a non-polar polar( non-polar, polar ) head group
Which component of the membrane regulates fluidity?
amphipathic
lipid micelles
cholesterol
potassium
Which proteins are not inserted into the membrane but rather associate with the membrane itself or another membrane protein?
integral transmembrane proteins
peripheral membrane-associated proteins
integral outer membrane proteins
integral inner membrane proteins
Integral proteins cannot can( cannot, can ) be removed from the membrane without ripping it apart
Which of the following increases the permeability of the membrane?
membrane kinks
low temperature
high cholesterol
saturated fatty acids
The cell membrane is selectively permeable as it allows only some substances all substances most substances( only some substances, all substances, most substances ) to pass freely
The advantages of a selectively permeable cell membrane include (more than one correct answer):
permits an internal environment
facilitates chemical reactions
allows uptake of toxic chemicals
allows development of electrical potential
Which of the following is a characteristic of passive transport?
requires use of ATP
requires a concentration or electro-chemical gradient
must use membrane proteins
requires high temperatures
is the passive movement of molecules from one location to another, through thermal agitation
Diffusion reaches equilibrium over time, and at equilibrium, there is no net flux high flux no flux high net flux( no net flux, high flux, no flux, high net flux )
Which of the following is NOT a factor influencing the rate of simple diffusion?
concentration gradient
distance
viscosity
saturation
Fick's law equation in words is net flux = (concentration gradient)
Which two properties of molecules control their ability to permeate a cell membrane?
molecular mass
lipid solubility
temperature
surface area
Which of the following best defines facilitated diffusion?
The net movement of substances down their concentration gradient via specific transmembrane proteins
The net movement of substances down their concentration gradient
The transport of ions through ATP powered ion pumps
The transport of substances against their concentration gradient through use of transmembrane proteins and ATP
To transport a molecule via facilitated diffusion, the carrier protein has to bind to it, and only molecules with the appropriate part can fit into the specific binding site and thus be transported; this is known as
Which of the following is NOT a class of direct or primary active transport mechanisms?
Ion pumps
ABC system
Group translocation
Antiports
P-class ion pumps are made of a single protein two proteins( a single protein, two proteins ) with 4 2( 4, 2 ) trans-membrane subunits
Secondary/coupled active transport involves the accumulating of amino acids and sugars in transport processes which are driven by gradients
The difference between active and passive transport is that active transport expends produces( expends, produces ) energy (usually in the form of ATP ADP Light( ATP, ADP, Light ))
Which of the following regarding membrane proteins is correct?
Integral membrane proteins are amphipathic
Peripheral membrane proteins may span the entire membrane
Both peripheral and integral membrane proteins may be able to move laterally in the membrane
Integral membrane proteins may help confer cell shape and motility
One striking feature of plasma membrane structure is its symmetry, with the extracellular and cytoplasmic surfaces virtual mirror images of each other
One function of integral membrane proteins in the plasma membrane of cells is to form channels to allow passage of nonpolar solutes into the cell