Study Cards – SHARC Review|Questions with A+
Graded Rationales Latest Updated 2026
What is tonicity? Why does it matter if you are hypertonic or hypotonic? What happens to cells
in these conditions?
Tonicity: the ability of a solution to cause a cell to shrink or swell
Hypertonic Solution: A solution having greater solute concentration than that of the cytosol
Cell will lose water and shrink (crenation)
Hypotonic Solution: A solution having lesser solute concentration than that of the cytosol.
Cell will gain water and rupture or swell (lyse)
Isotonic: equal concentration in solution and cytosol. (No movement)
Significance: influences blood pressure and flow
What is the difference between diffusion, facilitated diffusion and active transport? When are
they used? For which substances?
-(Simple)Diffusion: (passive) = hydrophobic "stuff" high → low
Lipid-soluble compounds (alcohols, fatty acids, and steroids)
Dissolved gases (Oxygen and Carbon Dioxide)"
osmosis
-(Facilitated Diffusion) Carrier-mediated transport: (passive or active) = Hydrophilic "stuff" =
water-soluble compounds, ions
Depends on size, charge and interaction with channel
Usually active transport goes against gradients
Need a carrier protein in order to pass through the membrane
-(Bulk Transport)Vesicular Transport (Active) low → high
Always active (Require energy and ATP)
-Endocytosis: materials into cell in vesicle→ pinocytosis or phagocytosis
-Exocytosis: released from a cell
What is hydrolysis?
A reaction involving the breaking of a bond in a molecule using water.
Why do you need O2? How is it transported in the blood?
O2 is used in cellular respiration to create ATP
O2 is transported through the body by hemoglobin which is found in Red Blood Cells (RBC's)
, Why do we need to get rid of CO2? What happens to pH if we have too much CO2?
Makes blood acidic
It decreases pH
Makes hemoglobin proteins release their oxygen
How is pH measured? Which organs help you to maintain pH homeostasis?
a) Concentration of H+ ions, 0-14. 0-6 = Acidic, 8-14 = Basic
b) Urinary, Respiratory, and Digestive
What are innate defenses? What are the specific defenses of your body?
INNATE DEFENSES: nonspecific= present at birth (against any type of invading agent)
1.physical barriers: keep hazardous material out of body
-epidermis, mucous membranes, nose hairs, cilia, fluids
2.phagocytes: attack and remove
-microphages, macrophages
3.immunological surveillance: monitors normal tissues
-natural killer cells: identify and attach to abnormal cells
4.interferons: proteins made and released by lymphocytes
-type of cytokine, increase resistance of cells to viral infection/slow disease
5.complementric: (proteins) complement action of antibodies
-attack and lyses, attract phagocytes, enhance inflammation
6.inflammation: inflammatory response
-destroys microbes, initiates tissue repair
7.fever: high body temperature
-hypothalamus, speeds up action that aid repair
SPECIFIC DEFENSES: protect against specific pathogen
1.T cells: cell-mediated immunity= can destroy pathogens in cell
2.B cells: antibody-mediated immunity= defend against antigens and pathogens in fluids
How is the resting potential determined? Which ions are involved? Which transporters?
a) Concentration of ions is different inside and outside of the cell. => -70mV
bi) Extracellular Fluid is rich in Na+ and Cl-
bii) Cytosol is full of K+, organic phosphate, and Protein (negatively charged)
biii) Membrane permeability differs for Na+ and K+, though it's usually more permeable to K+
(thus, the leaky channels).
c) Na+ / K+ Pump
What does the Na+, K+ ATPase do? Why is it important?