Quiz and Poll Questions for Midterm 1 Flashcards
Why is physiology considered an integrated science?
A) It encompasses many scientific disciplines
B) It contains emergent properties
C) Many organ systems are integrated into one physiological function
D) All of the above
D) All of the above
For any variable in the body that remains constant, when there is an increase in this variable there must be an equal removal. This is defined as
A) Emergent properties
B) Homeostasis
C) Mass balance
D) Physiology
C) Mass balance
An increase in core body temperature results in increased blood flow to the skin throughout the body so that heat can be released to the environment and bring core body temperature down. This is an example of what control system?
A) Local control
B) Negative feedback control
C) Positive feedback control
D) Feedforward control
E) None of the above
B) Negative feedback control
True or false? All homeostatic set points for variables in the body remain constant?
False
What is the most abundant lipid in the cell membrane?
A) glycolipid
B) Phospholipid
C) Sphingolipid
D) Cholesterol
E) None of the above
B) Phospholipid
How much water is contained within the body of a healthy 100kg male?
A) 60L
B) 42L
C) 28L
D) 14L
A) 60L
An increase in this type of tissue explains why, on average, females tend to have a slightly lower body water content when compared to males
A) Skeletal muscle
B) Adipose
C)Bone
D) Connective tissue
B) Adipose
If a cell swells in response to being exposed to a solution, the solution is said to be
A) Hyperosmotic
B) Hyposmotic
C) Hypertonic
D) Hypotonic
D) Hypotonic
Which of the following would increase the rate of diffusion?
A) Lower temperature
B) Thicker membrane
C) Smaller concentration gradient
D) Larger membrane surface area
D) Larger membrane surface area
True or false? Carrier proteins always require an external energy source such as ATP
False
Aquaporins are an example of what type of channel?
A) Mechanically gated
B) Ligand gated
C) Voltage gated
D) Leak
D) Leak
Saturation refers to:
A) A group of carrier proteins operating at their maximum rate
B) When two molecules attempt to use the same carrier
C) Whether a carrier protein has the ability to transport only one molecule or a group of closely related molecules
D) None of the above
A) A group of carrier proteins operating at their maximum rate
Clarathin-coated pits and caveolae are use in which transport process?
A) Exocytosis
B) Endocytosis
C) Phagocytosis
D) All of the above
B) Endocytosis
True or false? If a concentration gradient for an ION exists between the ICF and ECF that ion will move down it’s concentration gradient until equilibrium is reached
False
Which of the following statements about the resting membrane potential is TRUE?
A) It is equal to 0 mV
B) The inside of the membrane is positively charged compared to the outside
C) It results, in part, from the permeability of the cell membrane to K+
D) It is due to the presence of extracellular proteins
E) None of the above
C
If a cell has a resting membrane potential of -70mV and the membrane potential suddenly changes to +10mV, the cell is:
A )Hyperpolarizing
B) Depolarizing
C) Repolarizing
D) None of the above
B
A) Soma
B) axon
C) axon terminal
D) dendrite
C
Axonal movement of membrane bound proteins and mitochondria occurs via (Blank) axonal transport and when movement is from the cell body to the axon terminal it is considered (Blank)
A) Fast, retrograde
B) Slow, anterograde
C) Fast, anterograde
D) Slow, retrograde
C
If a nerve only contains motor neurons it is considered a:
A) mixed nerve
B) afferent nerve
C) efferent nerve
D) none of the above
C
A second action potential cannot be generated during the relative refractory period.
True
False
False
Which of the following will best increase the conduction rate of action potentials?
A) Increase the diameter of the axon, decrease the resistance of the axon membrane to ion leakage
B) Increase the diameter of the axon, increase the resistance of the axon membrane to ion leakage.
C) Decrease the diameter of the axon, decrease the resistance of the axon membrane to ion leakage.
D) Decrease the diameter of the axon, increase the resistance of the axon membrane to ion leakage
B
These glial cells act as scavengers, destroying foreign invaders.
A) Schwann cells
B) Astrocytes
C) Microglia
D) Oligodendrocytes
E) None of the above
C
Axons of neurons in both the peripheral and central nervous system are readily capable of undergoing regeneration when damage occurs.
True
False
False -Only neurons in CNS can regenerate slowly over time
The flow of current in a cell depends on:
A) Change in voltage across the cell membrane
B) The resistance of the cell membrane
C) The internal resistance of the cytoplasm
D) All of the above
D
Which of the following is NOT a correct characterisitc of graded potentials?
A) Are often initiated by the opening of ligand gated ion channels
B) Amplitude of the signal decays as it travels away from the stimulus point
C) Are initiated at the trigger zone
D) Can be depolarizing or hyperpolarizing
C
This neurocrine is released from a presynaptic cell and causes a RAPID response in a nearby postsynatpic cell:
A) Neurotransmitter
B) Neuromodulator
C) Neurohormone
D) Autocrine
E) None of the above
A
Which of the following is NOT a method for terminating neurotransmitter activity?
A) diffusion out of the synaptic cleft
B) spontaneous breakdown of neurotransmitter
C) Reuptake into axon terminal
D) Uptake into glial cells
E) Enzymatic degredation of neurotransmitter
B
Exocytosis of neurotransmitters or neuromodulators from the axon terminal is triggered by the entrance of:
A) Na+
B) K+
C) Cl-
D) Ca2+
E) None of the above
D
Spatial summation refers to:
A) electrical signals reaching neurons from outer space
B) multiple graded potentials from separate stimuli arriving at one location (axon hillock) simultaneously.
C) repeated graded potentials from a single stimulus point reaching the trigger zone nearly simultaneously.
D) suprathreshold potentials triggering action potentials that are of larger amplitude
E) None of the above
B
The tonicity of a solution depends only upon the __________.
A) total concentration of solutes, taking into account that some single molecules (such as salts, e.g., NaCl) ionize into more than one solute
B) total concentration of solutes as initially added to the solvent when making the solution
C) concentration of non-penetrating solutes
D) concentration of penetrating solutes
C
If a swimmer cuts his foot on a seashell while wading in the ocean and bleeds into the seawater, his erythrocytes will shrink. What does this tell us about the relative tonicities of the solutions?
A) The ocean is isotonic to the erythrocytes.
B) The ocean is hypotonic to the erythrocytes.
C) The ocean is hypertonic to the erythrocytes.
D) The cell membrane is not permeable to seawater.
C
The fluid compartments of the human body are in osmotic equilibrium. This means that the ICF and the ECF have the same total solute concentrations, despite the differences in their specific solute composition. Osmotic equilibrium occurs because water passes freely through cell membranes using open channels or the water channels called aquaporins.
If the osmolarity in one compartment changes, water moves by osmosis to bring the two compartments back to osmotic equilibrium. Water moves down its own gradient into the compartment with the higher osmolarity until both compartments have the same solute-to-volume ratio (or osmolarity).
Which of the following statements correctly describes the relationship between intracellular fluid (ICF) and extracellular fluid (ECF)?
A) The ICF and the ECF are in a chemical equilibrium.
B) All of the contents within the ICF are readily exchanged with the contents of the ECF.
C) The types of solutes and their distribution between the ICF and ECF are not the same.
D) Total solute concentration differs in the ECF when compared to the ICF.
C
Osmolarity is a way of expressing solute concentration taking into account whether or not the solute in question dissociates into ions when dissolved in water. For example, suppose a hypothetical salt, AB, completely dissociates into A+ and B- in water. One mole of AB in water would be one molar (1 M), but it would be 2 osmolar (2 OsM) solution, because there would be 1 mole of each ion dissolved in that solution. Thus, osmolarity is the measure of the number of solutes per volume of solution. Some salts, like NaCl, will incompletely dissociate into their respective ions when dissolved in water. Using the same principles, one mole of NaCl dissolved in a liter of water would become a 1 molar (1 M) NaCl solution, but would also be a 1.8 osmolar (1.8 OsM) solution. In the human body, we express this concentration in milliosmoles per liter (mOsM).
Presuming that the salts listed below completely dissociate in water, which of the following solutions below has the highest osmolarity?
A solution containing:
A) 7 mM sodium chloride (NaCl)
B) A mixed solution of 3 mM NaCl and 4 mM glucose
C) 7 mM glucose
D) A mixed solution of 4 mM NaCl and 3 mM glucose
A
You have a total body concentration of 300 mOsM and total body volume of 3 liters. If you add 0.5 L of a solution containing 150 mosmol of NaCl to the body, what would the new total body concentration be?
A) 350 mOsM
B) 300 mOsM
C) 450 mOsM
D) 700 mOsM
B
You have three separate beakers, each containing the following osmolarities:
A. 10 OsM
B. 13 OsM
C. 7 OsM
How would you describe the osmolarity of beaker A relative to beaker B?
A) Beaker A is isosmotic to beaker B.
B) Beaker A is hyposmotic to beaker B.
C) Beaker A is hyperosmotic to beaker B.
B
Which body fluid compartment has the smallest volume?
A) Intracellular fluid
B) Plasma
C) Interstitial fluid
D) Extracellular fluid
B
How can a solution be hyperosmotic but hypotonic?
A) If the concentration of nonpenetrating solutes is less in the solution than in a cell
B) If the total concentration of solutes in the solution is less than in a cell
C) If the concentration of penetrating solutes is higher in the solution than in a cell
D) If the amount of solutes is the same in the cell and solution
A
What will happen to the cells of a patient who is given an intravenous (IV) solution that is isosmotic to intracellular fluids?
A) The cells will shrink, because isosmotic solutions are hypertonic.
B) The question cannot be answered with certainty without knowing which solutes are present in the IV solution.
C) The cells will swell, because isosmotic solutions are hypotonic.
D) The cells will keep their normal shape, because isosmotic solutions result in no net change in water concentration.
B
Which two fluid compartments make up the extracellular fluid?
A) Cytosol and plasma
B) Intracellular fluid and plasma
C) Interstitial fluid and intracellular fluid
D) Plasma and interstitial fluid
D
What will occur if solution A, containing 400 mosmol/L nonpenetrating solute, were separated by a biological membrane from solution B, containing 600 mosmol/L nonpenetrating solute?
A) The volume of A would increase.
B) There would be no net volume change.
C) The volume of B would increase.
D) Water would flow from solution B to solution A.
C
How does the intracellular fluid compartment differ from the extracellular fluid compartment?
A) There is a higher concentration of potassium ions inside the cell than in the extracellular space.
B) There is a higher concentration of bicarbonate ion (HCO3 -) inside cells than in either the interstitial fluid or plasma.
C) There is a higher concentration of sodium ions inside the cell than in the extracellular space.
D) There is a higher concentration of protein in the interstitial fluid than in cells.
A
The cell membrane is made up of many different kinds of proteins. These proteins can be classified as either peripheral, transmembrane, or lipid-anchored proteins. Regardless of their classification, these proteins all play an important role in the function and integrity of a cell. Which of the following properly describes the function of membrane proteins?
Select all that apply.
A) to provide fluidity to the membrane
B) to combine with lipids to form strong shells that prevent the movement of substances across the membrane
C) to provide structural stability for the cell
D) to allow for cell-cell communication
E) to serve as a channel for the transport of molecules between extracellular and intracellular fluid
F) to combine with a carbohydrate, providing an immune response and/or cell recognition
G) to provide a selective barrier
C, D, E, F
Functions of the cell membrane include physical isolation, regulation of exchange, structural support, and which other function?
A) Radiation of heat to prevent protein denaturation and cell stress
B) Binding and delivery of oxygen
C) Extraction of energy from the environment for cell survival
D) Communication between the cell and its environment
D
Cell membranes are mainly made up of __________.
A) carbohydrates and proteins
B) lipids and proteins
C) nucleic acid and proteins
D) lipids and carbohydrates
B
Define interstitial fluid, indicating whether it is inside (intracellular) or outside (extracellular) cells.
A) Interstitial fluid is the intracellular fluid found in all cell types.
B) Interstitial fluid is the extracellular fluid inside the circulatory system.
C) Interstitial fluid is extracellular fluid outside the circulatory system and the cells.
D) Interstitial fluid is the intracellular fluid inside of the blood cells.
C
Glucose moves from the plasma into a skeletal muscle cell, where it is used for energy. Through which fluid compartment does glucose move between the plasma and the skeletal muscle cell?
A) Interstitial fluid
B) Extracellular fluid inside of C) blood vessels
D) Intracellular fluid
E) Cytosol
A
Where is most of the water in the body located?
A) Interstitial fluid
B) Plasma
C) Lumens of the digestive and urinary tracts
D) Intracellular fluid
D
Which of the following is a similarity among paracellular transport, transcellular transport, and transcytosis? All three:
Move large substances across epithelial membranes.
Your answer is not correct.
Are ways substances can be absorbed into the body.
This is the correct answer.
Require substances to move through epithelial cells.
Use protein transporters to absorb substances into the body.
According to Fick’s law of diffusion, diffusion rate is proportional to the surface area of the membrane, the concentration gradient, and which other variable?
The temperature of the solution
The permeability of the membrane
Your answer is correct.
The shape of the solute in solution
The temperature of the membrane
Active transport of substances across membranes requires ATP because __________.
more than one substance is transported at a time
the transported substances are not soluble in the lipid membrane
substances are moved against the concentration gradient (uphill)
Your answer is correct.
the transport protein moves or has moving gates
Which type of membrane transport generally requires that the transported substance dissolve in the lipid membrane?
Facilitated diffusion
Phagocytosis
Active transport
Simple diffusion
Water molecules can cross a cell membrane to enter a cell by several different mechanisms. Which answer choice is NOT a main way that water is transported into a cell?
Facilitated diffusion
Vesicular transport
Active transport
Your answer is correct.
Simple diffusion
What is the most important distinction between the membrane transporters known as channel proteins and those known as carrier proteins?
Channel proteins do not require energy, whereas carrier proteins do require energy.
Channel proteins create water-filled passages for small substances that do not bind to the protein. Carrier proteins transport larger substances by binding to them.
Your answer is correct.
Channel proteins transport only very small substances. Carrier proteins transport macromolecules.
Channel proteins transport water-soluble substances. Carrier proteins transport water-insoluble substance.
What must be true for diffusion of a solute to occur across a partition that separates two compartments?
The solute must be charged to pass through the partition.
The temperatures of the solutions must be different.
The concentrations of the solute must be high in both compartments.
The partition must be permeable to the solute.
Uric acid is transported across epithelial cells in the kidneys by an organic acid transporter (OAT) membrane transport protein. The presence of another organic acid, probenecid, causes a decrease in the uric acid transport rate. What characteristic of transporters is demonstrated by the decrease in uric acid transport in the presence of probenecid?
Maximum rate of transport
Saturation
Competition
Your answer is correct.
Specificity
The permeability of a membrane to a particular solute is related to which two variables, and what is the relationship?
It is directly proportional to both lipid solubility and the size of the solute.
It is inversely proportional to lipid solubility and directly proportional to the size of the solute.
It is directly proportional to lipid solubility and inversely proportional to the size of the solute.
Your answer is correct.
It is inversely proportional to both lipid solubility and size of the solute.
