Physiology Practice Exam
How many grams of sodium chloride do I need to make 1L of a 0.9% solution?
0.9% = 0.9g/100ml (9.9g NaCl/100ml) x (1000ml/L) x (1L) = 9.0g
A study involving human test subjects in which both the researcher and the test subjects are kept ignorant as to whether a subject is receiving the experimental treatment or a harmless, inactive substance is called a ____________ study. A third party that is not involved in the experiment holds the key as to who is receiving what.
Double-Blind
A chemical reaction releases energy. In physiology, this type of reaction is called:
Exergonic
How many grams does 2 moles of sodium chloride weigh?
116.88g = 117g if using significant figures.
What are the products per molecule of glucose of the Citric Acid Cycle, the preparatory step, and glycolysis combined. Include all products, not just the energy yield.
6 CO2, 10 NADH, 2 FADH2, 4 ATP
How many carbon atoms are in a mole of carbon?
6.02 x 10^23
What are ionic bonds?
A bond that forms due to the attraction between positively and negatively charged atoms.
What is G0 in reference to the cell cycle?
A quiescent period when the cell is performing its specialized function and not actively dividing
Tonicity is:
A relative term that describes the effect a solution has on cells of the body.
What are covalent bonds?
A strong bond that forms when atoms share electrons.
What are hydrogen bonds?
A weak bond between two polar molecules due to an attraction between partial positive and partial negative charge.
Water is a polar molecule, yet it easily moves through most cell membranes with the aid of specialized proteins called aquaporins. Which transport process is responsible?
Facilitated diffusion
True of False: Salivary glands are endocrine glands.
False
True or False: A hypertonic solution will cause a cell to swell.
False
True or False: Enzyme concentration has no effect on reaction rate.
False
True or False: Osmolarity and tonicity are synonyms; they mean the same thing.
False
True or False: The basolateral side of epithelial cells in the intestines faces the lumen of the digestive tract.
False
True or False: The conversion of pyruvate to lactate during anaerobic metabolism is irreversible
False
If a 10% sucrose solution (A) is separated from a 20% sucrose solution (B) by a membrane impermeable to sucrose but permeable to water, in which direction will net movement of water occur?
From the 10% sucrose solution (A) to the 20% sucrose solution (B) only
The cellular organelle(s) responsible for packaging and transporting proteins is/are the:
Golgi complex.
Which of the following is a cell-to-matrix junction?
Hemidesmosome
The unwanted material that is removed from a mRNA code during RNA processing is called:
Introns
An approach to physiology that is concerned about the biochemical, cellular, and tissuespecific responses and processes that make life possible is called the:
Mechanistic Approach
How many moles of carbon are in 10 grams?
Molecular Weight of Carbon = 12.01g/mole 10g x (mole/12.01g) = 0.8g =1g if you're using significant figures. Don't worry about significant figures if you don't know what they are.
30g of sodium bicarbonate are dissolved in enough water to make a 1L solution. What is the osmolarity of the solution? Assume that the dissociation constant for sodium bicarbonate is 2.
Molecular weight of sodium bicarbonate = 84.01 g/mol 1.0 mole sodium bicarbonate = 2.0 osmoles sodium bicarbonate (30 g/L) x (mol/84.01g) x (2.0 osmole/mole) = 0.71 osmoles
How many osmoles are in 0.5L of a 3.0M solution of sodium chloride? Assume that the dissociation for sodium chloride is 2.
Molecular weight of sodium chloride = 58.44g/mole 1.0 mole sodium chloride = 2.0 osmoles sodium chloride 3.0M = 3.0 mole/L (3.0 mole/L) x (0.5L) x (2 osmole/mole) = 3.0 osmoles
What is the molarity of a solution prepared by dissolving 15.0g of sodium chloride in enough water to make a 200mL solution?
Molecular weight of sodium chloride =58.44g/mol 1000ml = 1L (15.0g NaCl/200ml) x (1000ml/L) x (mol/58.44g) = 1.3g/mol
What are electrons?
Negatively charged particles that orbit the nucleus of an atom
What are neutrons?
Neutral particles found in the nucleus of an atom
Why do we breathe in oxygen?
Oxygen is the final electron acceptor in the electron transfer chain
The study of body function in a disease state is:
Pathophysiology
What are protons?
Positively charged particles found in the nucleus of an atom .
Homeostasis is the ability of the body to:
Quickly restore changed internal conditions to normal.
The alpha-helix and beta-pleated sheet are examples of the ________ structure of a protein
Secondary
In the citric acid cycle, the reactants Oxaloacetate and Acetyl CoA produce Citrate. How many carbons does Citrate have?
Six
Which ion is more concentrated in the extracellular fluid than in the intracellular fluid?
Sodium, Calcium, Chloride
Potential energy is:
Stored energy
ATP is invested (used) in which stage of glycolysis?
Sugar activation
What is the system that removes nitrogenous waste from the blood and excretes them?
The Urinary System
What is osmotic pressure?
The force required to oppose the movement of water through a membrane down water's concentration gradient
What happens to ionic compounds when they are dissolved in water?
The molecules dissociate into positive and negatively charged ions
What is osmosis?
The movement of water through a semi-permeable membrane down the concentration gradient of water until the concentration of water is equal on both sides of the membrane
An atom's potential to bond with another atom can be predicted in part by:
The number of electrons found in its valence shell
Two solutions (A and B) are separated by a membrane that is permeable to water but not to solutes. Solution A was prepared by dissolving 5g of sodium chloride in 10L of water. Solution B was prepared by dissolving 12g of sodium chloride in 6L of water. a. What is the osmolarity of side A in the initial condition before osmotic equilibrium has been established? b. What is the osmolarity of side B in the initial condition before osmotic equilibrium has been established? c. (1.0pt) Which direction will water flow to establish osmotic equilibrium in the condition above? (From A to B, from B to A, or there will be no net movement of water?)
A. Molecular weight of sodium chloride = 58.44g/mole 1.0 mole NaCl = 2.0 osmoles (5g NaCl/10L) x (mol/58.44g) X (2.0 osmole/mole) = 0.017 osmoles B. Molecular weight of sodium chloride = 58.44g/mole 1.0 mole NaCl = 2.0 osmoles (12g NaCl/6L) x (mol/58.44g) X (2.0 osmole/mole) = 0.068 osmoles C. Water follows the solute, so from A to B
A 5 liter solution with 20 osmoles of sucrose (side A) is separated from a 2 liter solution with 10 osmoles of sucrose (side B) by a membrane that is permeable to water but impermeable to sucrose. (See Figure 3). a. (1.0pt) Which direction will water flow? (From A to B, from B to A, or there will be no net movement of water?) Side A: 20 osmoles/5 L = 4 OsM. Side B: 10 osmoles/2L = 5 OsM b. (1.0pt) Which direction will water flow if the membrane is permeable to both sucrose in water? (From A to B, from B to A, or there will be no net movement of water?)
A. From side A to B B. The solute will move to equilibrium, which means that both sides will have 4.5 OsM. Therefore, there will be no net movement of water.
Red blood cells are placed in a beaker filled with 0.5L of a 150mM NaCl solution. NaCl is a non-penetrating solute and cannot cross the red blood cell membrane. a. What will happen to the red blood cells? b. Is the solution above hypotonic, hypertonic, or isotonic?
A. What will happen to the red blood cells? Osmolarity of the RBCs = 300mOsM. Osmolarity of the solution = 150mM x (2.0 osmoles/mole) = 300 mOsM Nothing. The RBCs will neither shrink nor swell B. Is the solution above hypotonic, hypertonic, or isotonic? Isotonic
Enzymes increase the rate of a chemical reaction by lowering the __________ of the reaction:
Activation energy
Consider the graph on the right. Based on what you know about molecular interactions and enzyme function, what is RB57 for this particular enzyme?
An antagonist
A 24 hour cycle that controls various biological processes is called a:
Circadian Rhythm
What type of chemical bond is created when two atoms share electrons?
Covalent Bond
What are polar molecules?
Covalent molecules that share electrons unevenly
What are motor proteins?
They are specialized proteins that use cellular energy (ATP) to create movement through their interactions with the cytoskeleton.
Red blood cells are placed in a 0.5L solution containing 1.7 mg of sodium chloride. What will happen to the cells? Sodium Chloride has a molecular weight of 58.44g/mol and it dissociates into 2 osmoles per mole.
They will swell because the solution is hypotonic
This type of membrane protein extends all the way through the cell membrane into both the extra- and intracellular fluids:
Transmembrane Protein
True or False: A solution can be hyperosmotic and still be hypo- or isotonic
True
True or False: An isosmotic solution can also be hypotonic.
True
True or False: NADH is oxidized to yield NAD+
True
True or False: Protolysis can activate an enzyme.
True
True or False: Red blood cells placed into 400mM solution of Urea (a penetrating solute that does not dissociate) will swell.
True
What is Percent Solution?
a unit of concentration defined by the number of grams per 100 ml liquid
What is Molarity (M)?
a unit of concentration defined by the number of moles of a substance dissolved in one liter of liquid
Two solutions (A and B) are separated by a membrane that is permeable to water but not to solutes. Solution A contains 400osmoles of sodium chloride dispersed in a 5L solution. Solution B contains 240osmoles of sodium chloride dispersed in a 12L solution. a. What is the osmolarity of side A in the initial condition before osmotic equilibrium has been established? b. What is the osmolarity of side B in the initial condition before osmotic equilibrium has been established? c. Which direction will water flow to establish osmotic equilibrium in the condition above? (From A to B, from B to A, or there will be no net movement of water?)
a. 400 osmoles/5L = 80 osmoles/L = 80 OsM b. 240 osmoles/12L = 20 osmoles/L = 20 OsM c. From B to A
Red blood cells are placed in a beaker filled with 0.5L of solution containing 300mmoles of Urea. Urea is a penetrating solute and can cross the cell membrane. a. (1.0pt) What will happen to the red blood cell? b. (1.0pt) Is the solution above hypotonic, hypertonic, or isotonic?
a. What will happen to the red blood cell? Osmolarity of the RBCs = 300mOsM. Osmolarity of the solution = (300mmole/0.5L) x (1.0 osmoles/mole) = 600 mOsM However, urea will cross the membrane until at equilibrium. The osmolarity of the solution after urea has moved to equilibrium will be 600 mOsM/2, or 300mOsM. 300mOsM will be added to the RBCs, making the osmolarity of the RBCs 300mOsM + 300mOsM, or 600mOsM. The RBCs will therefore swell and probably rupture. b. Is the solution above hypotonic, hypertonic, or isotonic? The solution is hypotonic because it causes the cells to swell and lyse, even though the solution is hyperosmotic
Which liquid below has a highest pH?
ammonia
If a neutral atom gains an electron from its outer electron shell the atom:
becomes a negatively charged anion
A 300 mOsM urea solution is __________.
hyposmotic to a 200 mM solution of NaCl. (200mM NaCl = 400mOsM NaCl)
The concentration of H+ in body fluids is measured in terms of pH. pH is equal to the _______________ log of the hydrogen ion concentration, which means that high concentrations of H+ have a low pH.
negative
A substance dissolved in liquid is called a:
solute
A substance that dissolves another substance is called a:
solvent
