MCAT UPDATED 2026 PRACTICE EXAM QUESTIONS AND
ANSWERS SURE A+
✔✔An astronaut throws a baseball in space. Select all that will occur as a result of the
throw. - ✔✔As the ball is pushed forward (throughout the entire throwing motion) the
✔✔Which of the following is a possible molecular formula of a molecule with a molar
mass of 120 g/mol and an empirical formula of CH2O? - ✔✔c4h8o4
This answer satisfies both the empirical formula and the molar mass. This compound's
molar mass is calculated as follows: (4 x 12 g/mol) + (8 x 1 g/mol) + (4 x 16 g/mol) =
120 g/mol. Therefore, we know the molecular formula must contain 4 moles of carbon
and oxygen and 8 moles of hydrogen.
✔✔What is the molecular formula of a sample weighing 56 g that is composed of 48 g
carbon and 8 g hydrogen? - ✔✔cannot be determined
We were not given the molar mass of the compound, and therefore we cannot
determine the molecular formula.
✔✔How many grams of CO2 can be produced from the combustion of 88 g of propane
in the presence of excess oxygen? - ✔✔1. Derive a balanced chemical equation:
C3H8 + 5O2 -> 3CO2 + 4H2O
2. Use grams given to convert to moles of propane:
88 grams * 1 mol propane/44 grams propane = 2 mole propane
3. find moles of CO2, then convert to grams of Co2
6 moles CO2/2 mols propane * 44 grams CO2 = 264 grams CO2
✔✔Limiting Reactants Problem Steps - ✔✔1. start with balanced equation. Convert
grams to moles by dividing by molecular mass
2. Whichever amount is less, convert to either grams
✔✔percent yield - ✔✔actual yield/theoretical yield x 100
✔✔theoretical yield - ✔✔the maximum amount of product that can be produced from a
given amount of reactant in perfect conditions
✔✔mediating variable - ✔✔a variable that helps explain the relationship between two
other variables
✔✔moderating variable - ✔✔variable that alters the relation between the independent
variable and the dependent variable
,✔✔confounding variable - ✔✔a factor other than the independent variable that might
produce an effect in an experiment
✔✔withdrawal symptoms - ✔✔symptoms that occur after chronic use of a drug is
reduced or stopped; tends to produce *opposite* symptoms that occur while using the
substances.
✔✔opiod use response eye - ✔✔pupillary constriction
✔✔drive-reduction theory - ✔✔motivation arises from the desire to eliminate drives,
which create uncomfortable internal states
✔✔Depression and drive-reduction theory - ✔✔depression stems from a reduction in
the motivating forces of arousal
✔✔Yerkes-Dodson Law - ✔✔performance of a behavior tends to be negatively
impacted at high and low levels of arousal
✔✔optimal level of arousal - ✔✔can vary depending on the particular task or behavior.
Highly cognitive actions, like playing chess, have lower optimal levels of arousal, while
less cognitive and more physical actions, like playing basketball, typically require higher
levels of arousal.
✔✔Abnormal functioning of which brain region(s) plays a role in the development of
depression?
I. Frontal lobe
II. Limbic system structures
III. Hypothalamus - ✔✔I, II, and III
The frontal lobe is involved in humans' ability to project future consequences of current
actions (I). Limbic system structures regulate emotion and memory (II), and the
hypothalamus coordinates many hormones, some of which are involved in mood
regulation (III).
✔✔Incidence - ✔✔The number or rate of new cases of a particular condition during a
specific time.
✔✔Hans Eysenck - ✔✔first empirical study he published on genetics of personality in
1951, which investigated the trait of neuroticism in identical (i.e. monozygotic) and
fraternal (i.e. Dizygotic) twins
✔✔Abraham Maslow - ✔✔Humanistic psychologist known for his "Hierarchy of Needs"
and the concept of "self-actualization"
,✔✔B.F. Skinner - ✔✔Behaviorist that developed the theory of operant conditioning by
training pigeons and rats
✔✔Gordon Allport - ✔✔trait theory of personality; 3 levels of traits: cardinal, central, and
secondary
✔✔Ethnocentrism - ✔✔belief in the superiority of one's own ethnic group; propagated
from one generation to the next thru family
✔✔What small molecules can undergo simple diffusion freely through plasma
membrane? Why is this necessary? - ✔✔Gases, o2 and co2; respiration
✔✔What can also undergo simple diffusion, albeit not as freely as gases? - ✔✔Small,
uncharged, polar molecules (water, ethanol, urea)
✔✔Osmosis - ✔✔Simple diffusion of *solvents* (liquid that solutes are dissolved in,
almost always water)
✔✔What maters when looking at osmosis? - ✔✔The *TOTAL* concentration of solute
particles, not just one species
✔✔isotonic - ✔✔Describes a solution whose solute concentration is equal to the solute
concentration inside a cell
(patients are given isotonic solution, not pure water)
✔✔Hypotonic - ✔✔Referring to a solution that, when surrounding a cell, will cause the
cell to take up water. Happens when someone has water intoxication.
✔✔Osmotic pressure - ✔✔minimum amount of pressure that prevents further osmosis
✔✔Van't Hoff's Law - ✔✔*Π = iMRT* (osmotic pressure, for when only water can
permeate, i = number of particles per molecule of dissolved substrate,
M = total concentration of solute particles, R = ideal gas constant, T = temp in Kelvin)
✔✔Osmolarity - ✔✔molarity of ALL solute particles
✔✔Osmoles of NaCl - ✔✔2 (1 for Na, 1 of Cl)
Osmolarity = 2 mol/Liter
✔✔Sequence information travels from CNS to periphery - ✔✔cerebral cortex, spinal
cord, efferent neurons, interneurons, motor neurons, muscle tissue
, ✔✔efferent neurons - ✔✔neurons that take information from the brain (CNS) to the rest
of the body
✔✔afferent neurons - ✔✔neurons that take information from the senses to the brain
(CNS)
✔✔spinal nerves - ✔✔sensory and motor nerves that connect to the spinal cord
✔✔cranial nerves - ✔✔sensory and motor nerves that directly enter the skull
✔✔Mechanism of L-dopa - ✔✔increases dopamine concentration
✔✔L-DOPA - ✔✔a precursor to the neurotransmitters dopamine, norepinephrine, and
epinephrine.
✔✔Catecholamines - ✔✔dopamine, norepinephrine, epinephrine
✔✔Parkinson's disease - ✔✔a progressive disease that destroys brain cells and is
identified by muscular tremors, slowing of movement, and partial facial paralysis
✔✔spinal cord transection - ✔✔Injury that severs the cord loss of sensation & motor
control below the injury
✔✔G1 phase - ✔✔stage of interphase in which cell grows and performs its normal
functions
✔✔S phase - ✔✔The synthesis phase of the cell cycle; the portion of interphase during
which DNA is replicated.
✔✔G2 phase - ✔✔The second growth phase of the cell cycle, cell prepares for mitosis
✔✔Mitosis - ✔✔cell division in which the nucleus divides into nuclei containing the same
number of chromosomes
✔✔Which of the following is most likely to be a trait of cancer stem cells? - ✔✔Self-
renewal of undifferentiated stem cells
✔✔totipotent stem cells - ✔✔Stem cells that can differentiate into any type of
specialised cells found in organisms of that species.
✔✔pluripotent stem cells - ✔✔Stem cells that can become almost all types of tissues
and cells in the body.
✔✔cancer - ✔✔abnormal gene expression
ANSWERS SURE A+
✔✔An astronaut throws a baseball in space. Select all that will occur as a result of the
throw. - ✔✔As the ball is pushed forward (throughout the entire throwing motion) the
✔✔Which of the following is a possible molecular formula of a molecule with a molar
mass of 120 g/mol and an empirical formula of CH2O? - ✔✔c4h8o4
This answer satisfies both the empirical formula and the molar mass. This compound's
molar mass is calculated as follows: (4 x 12 g/mol) + (8 x 1 g/mol) + (4 x 16 g/mol) =
120 g/mol. Therefore, we know the molecular formula must contain 4 moles of carbon
and oxygen and 8 moles of hydrogen.
✔✔What is the molecular formula of a sample weighing 56 g that is composed of 48 g
carbon and 8 g hydrogen? - ✔✔cannot be determined
We were not given the molar mass of the compound, and therefore we cannot
determine the molecular formula.
✔✔How many grams of CO2 can be produced from the combustion of 88 g of propane
in the presence of excess oxygen? - ✔✔1. Derive a balanced chemical equation:
C3H8 + 5O2 -> 3CO2 + 4H2O
2. Use grams given to convert to moles of propane:
88 grams * 1 mol propane/44 grams propane = 2 mole propane
3. find moles of CO2, then convert to grams of Co2
6 moles CO2/2 mols propane * 44 grams CO2 = 264 grams CO2
✔✔Limiting Reactants Problem Steps - ✔✔1. start with balanced equation. Convert
grams to moles by dividing by molecular mass
2. Whichever amount is less, convert to either grams
✔✔percent yield - ✔✔actual yield/theoretical yield x 100
✔✔theoretical yield - ✔✔the maximum amount of product that can be produced from a
given amount of reactant in perfect conditions
✔✔mediating variable - ✔✔a variable that helps explain the relationship between two
other variables
✔✔moderating variable - ✔✔variable that alters the relation between the independent
variable and the dependent variable
,✔✔confounding variable - ✔✔a factor other than the independent variable that might
produce an effect in an experiment
✔✔withdrawal symptoms - ✔✔symptoms that occur after chronic use of a drug is
reduced or stopped; tends to produce *opposite* symptoms that occur while using the
substances.
✔✔opiod use response eye - ✔✔pupillary constriction
✔✔drive-reduction theory - ✔✔motivation arises from the desire to eliminate drives,
which create uncomfortable internal states
✔✔Depression and drive-reduction theory - ✔✔depression stems from a reduction in
the motivating forces of arousal
✔✔Yerkes-Dodson Law - ✔✔performance of a behavior tends to be negatively
impacted at high and low levels of arousal
✔✔optimal level of arousal - ✔✔can vary depending on the particular task or behavior.
Highly cognitive actions, like playing chess, have lower optimal levels of arousal, while
less cognitive and more physical actions, like playing basketball, typically require higher
levels of arousal.
✔✔Abnormal functioning of which brain region(s) plays a role in the development of
depression?
I. Frontal lobe
II. Limbic system structures
III. Hypothalamus - ✔✔I, II, and III
The frontal lobe is involved in humans' ability to project future consequences of current
actions (I). Limbic system structures regulate emotion and memory (II), and the
hypothalamus coordinates many hormones, some of which are involved in mood
regulation (III).
✔✔Incidence - ✔✔The number or rate of new cases of a particular condition during a
specific time.
✔✔Hans Eysenck - ✔✔first empirical study he published on genetics of personality in
1951, which investigated the trait of neuroticism in identical (i.e. monozygotic) and
fraternal (i.e. Dizygotic) twins
✔✔Abraham Maslow - ✔✔Humanistic psychologist known for his "Hierarchy of Needs"
and the concept of "self-actualization"
,✔✔B.F. Skinner - ✔✔Behaviorist that developed the theory of operant conditioning by
training pigeons and rats
✔✔Gordon Allport - ✔✔trait theory of personality; 3 levels of traits: cardinal, central, and
secondary
✔✔Ethnocentrism - ✔✔belief in the superiority of one's own ethnic group; propagated
from one generation to the next thru family
✔✔What small molecules can undergo simple diffusion freely through plasma
membrane? Why is this necessary? - ✔✔Gases, o2 and co2; respiration
✔✔What can also undergo simple diffusion, albeit not as freely as gases? - ✔✔Small,
uncharged, polar molecules (water, ethanol, urea)
✔✔Osmosis - ✔✔Simple diffusion of *solvents* (liquid that solutes are dissolved in,
almost always water)
✔✔What maters when looking at osmosis? - ✔✔The *TOTAL* concentration of solute
particles, not just one species
✔✔isotonic - ✔✔Describes a solution whose solute concentration is equal to the solute
concentration inside a cell
(patients are given isotonic solution, not pure water)
✔✔Hypotonic - ✔✔Referring to a solution that, when surrounding a cell, will cause the
cell to take up water. Happens when someone has water intoxication.
✔✔Osmotic pressure - ✔✔minimum amount of pressure that prevents further osmosis
✔✔Van't Hoff's Law - ✔✔*Π = iMRT* (osmotic pressure, for when only water can
permeate, i = number of particles per molecule of dissolved substrate,
M = total concentration of solute particles, R = ideal gas constant, T = temp in Kelvin)
✔✔Osmolarity - ✔✔molarity of ALL solute particles
✔✔Osmoles of NaCl - ✔✔2 (1 for Na, 1 of Cl)
Osmolarity = 2 mol/Liter
✔✔Sequence information travels from CNS to periphery - ✔✔cerebral cortex, spinal
cord, efferent neurons, interneurons, motor neurons, muscle tissue
, ✔✔efferent neurons - ✔✔neurons that take information from the brain (CNS) to the rest
of the body
✔✔afferent neurons - ✔✔neurons that take information from the senses to the brain
(CNS)
✔✔spinal nerves - ✔✔sensory and motor nerves that connect to the spinal cord
✔✔cranial nerves - ✔✔sensory and motor nerves that directly enter the skull
✔✔Mechanism of L-dopa - ✔✔increases dopamine concentration
✔✔L-DOPA - ✔✔a precursor to the neurotransmitters dopamine, norepinephrine, and
epinephrine.
✔✔Catecholamines - ✔✔dopamine, norepinephrine, epinephrine
✔✔Parkinson's disease - ✔✔a progressive disease that destroys brain cells and is
identified by muscular tremors, slowing of movement, and partial facial paralysis
✔✔spinal cord transection - ✔✔Injury that severs the cord loss of sensation & motor
control below the injury
✔✔G1 phase - ✔✔stage of interphase in which cell grows and performs its normal
functions
✔✔S phase - ✔✔The synthesis phase of the cell cycle; the portion of interphase during
which DNA is replicated.
✔✔G2 phase - ✔✔The second growth phase of the cell cycle, cell prepares for mitosis
✔✔Mitosis - ✔✔cell division in which the nucleus divides into nuclei containing the same
number of chromosomes
✔✔Which of the following is most likely to be a trait of cancer stem cells? - ✔✔Self-
renewal of undifferentiated stem cells
✔✔totipotent stem cells - ✔✔Stem cells that can differentiate into any type of
specialised cells found in organisms of that species.
✔✔pluripotent stem cells - ✔✔Stem cells that can become almost all types of tissues
and cells in the body.
✔✔cancer - ✔✔abnormal gene expression
