Exam 2 Flashcards
Plasma membrane proteins make up 50% of the mass of the plasma membrane and determine its function.Which is not a function of the plasma membrane proteins?
A)acting as enzymes B)acting as receptors C)transporting substance D)providing structural support E)acting in cell to cell recognition F)linking cells together G)all are functions
G
Which cell junction is correctly matched?
A)Desmond ones to communicating junctions
B)tight junctions to impermeable junctions
C)gap junctions to anchoring junctions
D)all are correctly matched
E)none are correctly matched
B
Which cell junctions electrically couple certain organs such as the heart and allow them to behave as a functional system? A)desmosomes B)tight junctions C)gap junctions D)a and b E)none of the above
C
Which membrane transport system does not require the cell to use ATP? A)primary active transport B)secondary active transport C)exocytosis D)osmosis E)phagocytosis F)pinocytosis
D
Which factors will not increase the rate of diffusion? A)increase in concentration difference B)increase in distance C)increase in temperature D)decrease in particle size E)none of the above
B
Which passive transport processes are saturable?
A)channel mediated facilitated diffusion
B)osmosis
C)carrier mediated facilitated diffusion
D)simple diffusion
E)a and c
E
If osmolarity of a solution increases, osmotic pressure increases,pulling pressure increases
True or false
True
When the hydrostatic pressure is equal to the osmotic pressure, there is no movement of water
True or false
True
Which is not an example of simple diffusion?
A)popcorn odor permeating a room
B)gas exchange in our lungs
C)a white blood cell engulfing our bacterium
D)a dissolving sugar cube
E)all are examples
C
When the movement of Na+ ions down their concentration gradient drives the transport of other substances across the cell membrane it is called
Secondary active transport
Cells that store large quantities of chemicals to be released do so in structures called
Vesicles
A red blood cell will crenate (shrink) when placed in what type of solution?
Hypertonic
Hemolysis will occur in a red blood cell when placed into what type of solution?
Hypotonic
Which statement is false regarding secondary active transport?
A)requires energy indirectly from ionic gradients
B)pluses potential energy from ionic gradients
C)a coupled system
D)uses ATP directly
It uses ATP directly
The concentration of k+ is 28x higher inside the cell than outside the cell. If a K+ channel was opened on the plasma membrane, in which direction will K+ flow?would the plasma membrane be more positive or negative?
Out of the cell: negative
The sodium potassium pump (Na and K)
Pumps Na+ out of and K+ into the cell
Exocytosis is transport _____of the cell, while endocytosis is _____the cell.
Out:in
Phagocytosis is _____, while pinocytosis is ______
Cell eating; cell drinking
A voltage or membrane potential exists only at the plasma membrane
True
Resting membrane potential is largely determined by K+
True or false
True
What is a ligand
Chemical messenger
1sr messenger
Molecule that binds receptor
Hormone or neurotransmitter
What is the second messenger?
An intracellular chemical signal
Based on your knowledge of the cell membranes chemistry, where would steroid hormones most likely interact with their target cell
Inside the target cells cytoplasm( or nucleus)
During which stage of the cells life cycle is DNA replicated
S phase
