MCAT Psychology Biological Bases of
Behavior Questions and Verified
Answers 2026
The nervous system - CORRECT ANSWERS -Includes the peripheral nervous system and central
nervous system. The nervous system is responsible for regulating and determining someone's
behavior in his or her environment.
Neurons - CORRECT ANSWERS -specialized cells that pick up and transmit nerve impulses.
Reflex arc - CORRECT ANSWERS -a set of neurons that are responsible for receiving reflexive
nerve impulses (e.g. If you touch a hot frying pan, the neurons contained within the reflex arc
will immediately react, causing you to withdraw your hand.)
Neurotransmitters - CORRECT ANSWERS -chemicals utilized by neurons to communicate and
transfer nerve impulses to other structures in the body (e.g. Muscle fiber). There are excitatory
neurotransmitters (e.g. Acetylcholine, norepinephrine) and inhibitory neurotransmitters (e.g.
Dopamine, serotonin)
With regards to behavior, various neurotransmitters affect different regions of the brain, which
can cause someone to feel and behave a certain way. Example: Serotonin is a neurotransmitter
that is responsible for feelings of happiness and well-being. High levels of serotonin would likely
cause someone to behave happily (high levels of self-care, socializing, etc.)
Structure and function of PNS - CORRECT ANSWERS -consists of all outside nerve fibers that are
not included within the brain or spinal cord. The PNS functions to send nerve impulses from our
limbs (skin, muscles) and trunk (organs) to the central nervous system for processing.
Structure and function of CNS - CORRECT ANSWERS -consists of the brain and spinal cord. Its
function is to receive and process nerve impulses from the PNS. It is also responsible for
thought processing and body movement.
Forebrain - CORRECT ANSWERS --consists of the cerebrum, thalamus, the limbic system, and
hypothalamus. Responsible for abstract thinking, logic, and emotions.
Midbrain - CORRECT ANSWERS -consists of the tegmentum, tectum, and cerebral peduncles.
Responsible for the production of dopamine, which regulates habituation and motivation. Also
plays a role in vision and hearing.
Hindbrain - CORRECT ANSWERS -consists of the cerebellum, pons, and medulla. Responsible for
vital bodily functions (motor control, respiratory and digestive reflexes) as well as sexual
arousal.
, Lateralization of cortical functions - CORRECT ANSWERS -some of our bodies' functions occur
predominantly by one side of the brain.
Left brain - CORRECT ANSWERS -processing the right visual field, grammar, positive emotions,
speech, and writing.
Right brain - CORRECT ANSWERS -processing the left visual field, negative emotions, recognition
of emotions, and spatial skills (e.g. Facial recognition).
Spinal cord - CORRECT ANSWERS -a bundle of nerve fibers located within the spinal column,
which connects the majority of the body to the brain.
Neuronal communication and behavior - CORRECT ANSWERS -Dopaminergic neurons are
stimulated by dopamine (a neurotransmitter that affects mood -> affects behavior)
Defective neurons can cause Parkinson's disease (impaired motor movements, loss of feeling)
and Alzheimer's disease (changes in mood, impaired movement and memory)
Endorphins - CORRECT ANSWERS -released during extreme pleasure or pain, can have a
numbing effect on pain
Norepinephrine - CORRECT ANSWERS -regulares alertness, learning, and long-term memory.
Deficiency can lead to mood disorders
Gamma-Amino Butyric Acid (GABA) - CORRECT ANSWERS -reduces the excitability of neurons
(deficiency can cause anxiety and depression).
Serotonin - CORRECT ANSWERS -regulates mood, sleep, libido (deficiency can cause anxiety and
depression).
Dopamine - CORRECT ANSWERS -plays a role in learning and ability to concentrate
Acetylcholine - CORRECT ANSWERS -regulates memory, sleep, and plays a role in learning
(deficiency is associated with dementia)
Epinephrine (adrenaline) - CORRECT ANSWERS -intensifies mood (released during fight or flight)
Hypothalamus - CORRECT ANSWERS -- controls the actions of the endocrine system.
Adrenal gland - CORRECT ANSWERS -release adrenaline during "fight or flight" situation.
Hypophysis (pituitary gland) - CORRECT ANSWERS -secretes growth and reproduction
hormones. Also secretes neurotransmitters.
Reproductive organs - CORRECT ANSWERS -Ovaries produce estrogen and progesterone, testes
produce testosterone.
Thyroid - CORRECT ANSWERS -regulates consumption of energy/ metabolism.
Behavior Questions and Verified
Answers 2026
The nervous system - CORRECT ANSWERS -Includes the peripheral nervous system and central
nervous system. The nervous system is responsible for regulating and determining someone's
behavior in his or her environment.
Neurons - CORRECT ANSWERS -specialized cells that pick up and transmit nerve impulses.
Reflex arc - CORRECT ANSWERS -a set of neurons that are responsible for receiving reflexive
nerve impulses (e.g. If you touch a hot frying pan, the neurons contained within the reflex arc
will immediately react, causing you to withdraw your hand.)
Neurotransmitters - CORRECT ANSWERS -chemicals utilized by neurons to communicate and
transfer nerve impulses to other structures in the body (e.g. Muscle fiber). There are excitatory
neurotransmitters (e.g. Acetylcholine, norepinephrine) and inhibitory neurotransmitters (e.g.
Dopamine, serotonin)
With regards to behavior, various neurotransmitters affect different regions of the brain, which
can cause someone to feel and behave a certain way. Example: Serotonin is a neurotransmitter
that is responsible for feelings of happiness and well-being. High levels of serotonin would likely
cause someone to behave happily (high levels of self-care, socializing, etc.)
Structure and function of PNS - CORRECT ANSWERS -consists of all outside nerve fibers that are
not included within the brain or spinal cord. The PNS functions to send nerve impulses from our
limbs (skin, muscles) and trunk (organs) to the central nervous system for processing.
Structure and function of CNS - CORRECT ANSWERS -consists of the brain and spinal cord. Its
function is to receive and process nerve impulses from the PNS. It is also responsible for
thought processing and body movement.
Forebrain - CORRECT ANSWERS --consists of the cerebrum, thalamus, the limbic system, and
hypothalamus. Responsible for abstract thinking, logic, and emotions.
Midbrain - CORRECT ANSWERS -consists of the tegmentum, tectum, and cerebral peduncles.
Responsible for the production of dopamine, which regulates habituation and motivation. Also
plays a role in vision and hearing.
Hindbrain - CORRECT ANSWERS -consists of the cerebellum, pons, and medulla. Responsible for
vital bodily functions (motor control, respiratory and digestive reflexes) as well as sexual
arousal.
, Lateralization of cortical functions - CORRECT ANSWERS -some of our bodies' functions occur
predominantly by one side of the brain.
Left brain - CORRECT ANSWERS -processing the right visual field, grammar, positive emotions,
speech, and writing.
Right brain - CORRECT ANSWERS -processing the left visual field, negative emotions, recognition
of emotions, and spatial skills (e.g. Facial recognition).
Spinal cord - CORRECT ANSWERS -a bundle of nerve fibers located within the spinal column,
which connects the majority of the body to the brain.
Neuronal communication and behavior - CORRECT ANSWERS -Dopaminergic neurons are
stimulated by dopamine (a neurotransmitter that affects mood -> affects behavior)
Defective neurons can cause Parkinson's disease (impaired motor movements, loss of feeling)
and Alzheimer's disease (changes in mood, impaired movement and memory)
Endorphins - CORRECT ANSWERS -released during extreme pleasure or pain, can have a
numbing effect on pain
Norepinephrine - CORRECT ANSWERS -regulares alertness, learning, and long-term memory.
Deficiency can lead to mood disorders
Gamma-Amino Butyric Acid (GABA) - CORRECT ANSWERS -reduces the excitability of neurons
(deficiency can cause anxiety and depression).
Serotonin - CORRECT ANSWERS -regulates mood, sleep, libido (deficiency can cause anxiety and
depression).
Dopamine - CORRECT ANSWERS -plays a role in learning and ability to concentrate
Acetylcholine - CORRECT ANSWERS -regulates memory, sleep, and plays a role in learning
(deficiency is associated with dementia)
Epinephrine (adrenaline) - CORRECT ANSWERS -intensifies mood (released during fight or flight)
Hypothalamus - CORRECT ANSWERS -- controls the actions of the endocrine system.
Adrenal gland - CORRECT ANSWERS -release adrenaline during "fight or flight" situation.
Hypophysis (pituitary gland) - CORRECT ANSWERS -secretes growth and reproduction
hormones. Also secretes neurotransmitters.
Reproductive organs - CORRECT ANSWERS -Ovaries produce estrogen and progesterone, testes
produce testosterone.
Thyroid - CORRECT ANSWERS -regulates consumption of energy/ metabolism.
