Biology Psychology
female sex hormones are released by the:
ovaries
endorphins
"morphine within"--natural, opiate-like neurotransmitters linked to pain control and to pleasure
match the scanning technique with the correct description. 1. fMRI scan 2. PET scan 3. MRI scan -------------------------------- a. tracks radioactive glucose to reveal brain activity b. tracks successive images of brain tissue to show brain function c. uses magnetic fields and radio waves to show brain anatomy
1. b 2. a 3. c
match the type of neuron to its description: 1. motor neurons 2. sensory neurons 3. interneurons ------------------------------------ a. carry incoming messages from sensory receptors to the CNS b. communicate within the CNS and process information between incoming and outgoing messages c. carry outgoing messages from the CNS to muscles and glands
1. c 2. a 3. b
in what brain region would damage be most likely to (1) disrupt your ability to jump rope? (2) disrupt your ability to hear? (3) leave you in a coma? (4) cut off the very breath and heartbeat of life?
1. cerebellum 2. thalamus 3. reticular formation 4. medulla
what does the medulla do?
controls heartbeat and breathing
which of the following scanning techniques measures glucose consumption as an indicator of brain activity?
PET
how do CTs work?
X-rays of the head generate images that may locate brain damage
MEG (magnetoencephalography)
a brain imaging technique that measures magnetic fields from the brain's natural electrical activity
myelin sheath
a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next
how do MEGs work?
a head coil records magnetic fields from the brain's natural electrical currents
glutamate
a major excitatory neurotransmitter which is involved in memory; oversupply can overstimulate the brain, producing migraines or seizures (which is why some people avoid MSG, monosodium glutamate, in food)
GABA
a major inhibitory neurotransmitter; undersupply linked to seizures, tremors, and insomnia
agonist
a molecule that increases a neurotransmitter's action
antagonist
a molecule that inhibits or blocks a neurotransmitter's action
neuron
a nerve cell; the basic building block of the nervous system
reticular formation
a nerve network that travels through the brainstem into the thalamus and plays an important role in controlling arousal
hippocampus
a neural center located in the limbic system; helps process for storage explicit (conscious) memories of facts and events
action potential
a neural impulse; a brief electrical charge that travels down an axon
hypothalamus
a neural structure lying below (hypo) the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward
the reticular formation is:
a neuron network extending from the spinal cord right up through the thalamus. as the spinal cord's sensory input flows up to the thalamus, some of it travels through the reticular formation, which filters incoming stimuli and relays important information to other brain areas. the reticular formation also controls arousal.
dendrites
a neuron's often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body
all-or-none response
a neuron's reaction of either firing (with a full-strength response) or not firing
reuptake
a neurotransmitter's reabsorption by the sending neuron
adrenal glands
a pair of endocrine glands that sit just above the kidneys and secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress
CT (computed tomography) scan
a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice of the brain's structure
reflex
a simple, automatic response to a sensory stimulus, such as a knee-jerk response
fMRI (functional MRI)
a technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function as well as structure
MRI (magnetic resonance imaging)
a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue. MRI scans show brain anatomy
PET (positron emission tomography) scan
a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task
thyroid gland
affects metabolism
serotonin
affects mood, huner, sleep, and arousal; undersupply linked to depression. some drugs that raise serotonin levels are used to treat depression.
stimulation of the amygdala is most likely to have which of the following effects?
aggression
morphine is similar to the body's endorphins in that both elevate mood and ease pain. in this instance, morphine is considered to be an:
agonist
how do agonists work?
agonists mimic neurotransmitters, opening receptor sites.
EEG (electroencephalogram)
an amplified recording of the waves of electrical activity sweeping across the brain's surface. these waves are measured by electrodes placed on the scalp
why are we biopsychosocial systems?
an individual is a part of a family, culture, and community
how do antagonists work?
antagonists block neurotransmitters from opening receptor sites.
corpus callosum
axon fibers connecting the two cerebral hemispheres
how are the nervous and endocrine systems alike, and how do they differ?
both of these communication systems produce chemical molecules that act on the body's receptors to influence our behavior and emotions. the endocrine system, which secretes hormones into the bloodstream, delivers its messages much more slowly than the speedy nervous system, and the effects of the endocrine system's messages tend to linger much longer than those of the nervous system.
what is the hippocampus?
brain structure linked to conscious memory
what is the amygdala?
brain structure linked to emotion
the ______________________ is a crossover point where nerves from the left side of the brain are mostly linked to the right side of the body, and vice versa.
brainstem
the medulla and pons make up the:
brainstem
nerves
bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs
how do neuroscientists study the brain's connections to behavior and mind?
case studies and lesioning first revealed the general effects of brain damage. modern electrical, chemical, or magnetic stimulation has also revealed aspects of information processing in the brain. CT and MRI scans show anatomy. EEG, MEG, PET, and fMRI recordings reveal brain function.
glial cells
cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory
a gymnast falls and hits her head on the floor. she attempts to continue practicing but has trouble maintaining balance. what part of her brain has probably been affected?
cerebellum
hormones are _________________ released into the bloodstream.
chemical messengers
hormones
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
neurotransmitters
chemical messengers that cross the synaptic gaps between neurons. when released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse
parasympathetic nervous system:
contracts pupils, slows heartbeat, stimulates digestion, stimulates gallbladder, contracts bladder, and allows blood flow to sex organs
what does the hypothalamus do?
controls maintenance functions such as eating; helps govern endocrine system; linked to emotion and reward
what does the cerebellum do?
coordinates voluntary movement and balance and supports learning and memories of such
karl's doctor is concerned about a loss of neural functioning in karl's brain. explain how loss of each of the following might make karl's reaction time slower. - myelin sheath - ACh
damage to the myelin sheath would slow down neural impulses and cause the message to travel slower which makes the muscles move slower. ACh is the neurotransmitter involved in muscle action. the doctor might look to see if karl was producing enough of this neurotransmitter.
when a neuron fires an action potential, the information travels through the axon, the dendrites, and the cell body, but no that order. place these three structures in the correct order.
dendrites, cell body, axon
sympathetic nervous system:
dilates pupils, accelerates heartbeat, inhibits digestion, stimulates glucose release by liver, stimulates secretion of epinephrine and norepinephrine, relaxes bladder, and stimulates ejaculation in males
neurotransmitter pathways
each of the brain's differing chemical messengers has designated pathways where it operates.
neural impulse
electrical signal traveling down the axon
how do EEGs work?
electrodes placed on the scalp measure electrical activity in the neurons
acetylcholine (ACh)
enables muscle action, learning, and memory; with alzheimer's disease, ACh-producting neurons deteriorate
the cerebellum's functions include:
enabling nonverbal learning and skill memory, helps us judge time, modulate our emotions, discriminate sounds and textures, and it coordinates voluntary movement.
in order for a neuron to generate an action potential, which of the following must be true?
excitatory impulses must outnumber inhibitory impulses.
terminal branches of axon
form junctions with other cells
the medulla controls:
heartbeat and breathing
parathyroids
help regulate the level of calcium in the blood
norepinephrine
helps control alertness and arousal; undersupply can depress mood
what does reticular formation do?
helps control arousal
what do the pons do?
helps coordinate movement and control sleep
damage to which of the following brain structures would affect the processing of new explicit memories?
hippocampus
which of the following brain areas is responsible for regulating hunger and thirst?
hypothalamus
which of the following communicates with the pituitary, which in turn controls the endocrine system?
hypothalamus
what muscles and glands does the endocrine system include?
hypothalamus, thyroid gland, parathyroids, pituitary gland, pancreas, adrenal glands, testis, and ovary
refractory period
in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state
dopamine
influences movement, learning, attention, and emotion; oversupply linked to schizophrenia. undersupply linked to tremors and decreased mobility in parkinson's disease
what happens when we touch a flame with our fingers?
information is carried from skin receptors along a sensory neuron to the spinal cord. from there it is passed via interneurons to motor neurons that lead to the muscles in the hand and arm. because this reflex involves only the spinal cord, the hand jerks away from the candle flame even before information about the event has reached the brain, causing the experience of pain.
if you accidentally touch a hot stove, which of the following is responsible for moving your hand away before you even realize what you have done?
interneuron
inhibitory
like pushing a neuron's brake
excitatory
like pushing a neuron's gas pedal
what is the pituitary gland?
master endocrine gland
how do fMRIs work?
measures blood flow to brain regions by comparing continuous MRI scans
damage to which of the following puts a person's life in the most danger because it may cause breathing to stop?
medulla
what happens if the myelin degenerates?
multiple sclerosis results: communication to muscles slows, with eventual loss of muscle control
multiple sclerosis is a result of degeneration in the:
myelin sheath
the body's wiring:
nerves from the left side of the brain are mostly linked to the right side of the body, and vice versa.
he functional divisions of the human nervous system:
nervous system | | ---------------------- Peripheral Central | | ---------------------------- Autonomic Somatic | | | | Sympathetic Sensory Input Parasympathetic Motor Output
how is a neural impulse fired?
neural stimulation causes the positive sodium ions outside a neuron and the negative sodium ions inside the neuron to switch, which produces a momentary depolarization called the action potential. the action potential influences the electrical charge of the next portion of the axon. meanwhile, other gates open in the first part of the axon, allowing potassium ions to flow out, repolarizing this section. as the action potential moves speedily down the axon, sodium and potassium pumps in the cell membrane finish restoring the first section of the axon to its resting potential.
limbic system
neural system (including the amygdala, hypothalamus, and hippocampus) located below the cerebral hemispheres; associated with emotions and drives
what are the parts of a neuron, and how are neural impulses generated?
neurons are the elementary components of the nervous system, the body's speedy electrochemical information system. a neuron consists of a cell body and its branching fibers. it receives signals through its dendrites and sends signals through its axons. some axons are encased in a myelin sheath, which enables faster transmission. glial cells support nerve cells and participate in learning, thinking, and memory. if the combined received signals exceed a minimum threshold, the neuron fires, transmitting an electrical impulse (the action potential) down its axon by means of a chemistry-to-electricity process. the neuron's reaction is an all-or-none response.
what happens in the synaptic gap?
neurons send neurotransmitters (chemical messengers) across this tiny space between one neurons terminal branch and the next neuron's dendrite or cell body.
sensory (afferent) neurons
neurons that carry incoming information from the body's tissues and sensory receptors to the brain and spinal cord
motor (efferent) neurons
neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
interneurons
neurons within the brain and spinal cord; they process information between the sensory inputs and motor outputs
serotonin, dopamine, and endorphins are all chemical messengers called:
neurotransmitters
difference between neurotransmitters and drugs:
neurotransmitters are produced inside the body. they can excite and inhibit neural communication. drugs and other chemicals come from outside the body. they can have an agonistic effect or an antagonistic effect on neurotransmission.
how do neurotransmitters influence behavior, and how do drugs and other chemicals affect neurotransmission?
neurotransmitters travel designated pathways in the brain and may influence specific behaviors and emotions. acetylcholine (ACh) affects muscle action, learning, and memory. endorphins are natural opiates released in response to pain and exercise. drugs and other chemicals affect brain chemistry at synapses. agonists excite by mimicking particular neurotransmitters. antagonists inhibit a particular neurotransmitter's release or block its effect.
which division of the autonomic nervous system calms a person down once a stressful event has passed?
parasympathetic
what does the spinal cord do?
pathway for neural fibers traveling to and from the brain; controls simple reflexes
how do MRIs work?
people sit or lie down in a chamber that uses magnetic fields and radio waves to provide a map of brain structure
which of the following endocrine glands may explain unusually tall height in a 12-year-old?
pituitary gland
resting potential
positive-outside/negative-inside
pancreas
regulates the level of sugar in the blood
what does the thalamus do?
relays messages between lower brain centers and cerebral cortex
why are psychologists concerned with human biology?
researchers working from a biological perspective study the links between our biology and our behavior. we are biopsychosocial systems: biological, psychological, and social-cultural factors interact to influence behavior.
why is the pituitary gland called the "master gland"?
responding to signals from the hypothalamus, the pituitary releases hormones that trigger other endocrine glands to secrete hormones, which in turn influence the brain and behavior.
what bodily changes does your ANS direct before and after you give an important speech?
responding to this challenge, you ANS sympathetic division will arouse you. it accelerates your heartbeat, raises your blood pressure and blood sugar, slows your digestion, and cools you with perspiration. after you give the speech, you ANS parasympathetic division will reverse these effects.
what is reuptake? what two other things can happen to excess neurotransmitters after a neuron reacts?
reuptake occurs when excess neurotransmitters are reabsorbed by the sending neuron. they can also drift away or be broken down by enzymes.
when there is a negative charge inside an axon and a positive charge outside of it, the neuron is:
said to have a resting potential
ovary
secretes female sex hormones
testis
secretes male sex hormones
biology of antidepressants
selective serotonin reuptake inhibitors (SSRIs) are popularly prescribed antidepressants. they relieve depression by partially blocking the reuptake of the neurotransmitter serotonin.
the thalamus acts as the brain's:
sensory control center; it receives information from all the senses except smell, and routes that information to the higher brain regions that deal with seeing, hearing, tasting, and touching. the thalamus also receives some of the higher brain's replies, which it then directs to the medulla and to the cerebellum.
while walking barefoot, you step on a piece of glass. before you have a chance to consciously process what has happened, you draw your foot away from the glass. identify and explain the three types of neurons that deal with information regarding this painful stimulus.
sensory neurons carry information from the point of the injury to the central nervous system. interneurons are neurons within the brain and spinal cord. interneurons would help you interpret the pain and enable your spinal cord to send out marching orders. motor neurons carry the instruction from the central nervous system to activate the muscles in your leg and foot.
which neurotransmitters are most likely in undersupply in someone who is depressed?
serotonin and norepinephrine
the pons control:
sleep and help coordinate movements
which division of the nervous system enables a person to move the muscles necessary to walk down the street?
somatic
phrenology has been discredited, but which of the following ideas has its origins in phrenology?
specific areas of the brain control specific functions
how does our nervous system allow us to experience the difference between a slap and a tap on the back?
stronger stimuli (the slap) cause more neurons to fire and to fire more frequently than happens with weaker stimuli (the tap)
what is phrenology?
study introduced by Franz Gall in 1800s that proposed that the bumps on the skull could reveal a person's underlying brain size and associated mental abilities and character traits
electrical stimulation of a cat's amygdala provokes angry reactions. which autonomic nervous system division is activated by such stimulation?
sympathetic nervous system
neurotransmitters cross the _______________ to carry information to the next neuron.
synaptic gap
which of the following is sometimes referred to as the brain's sensory switchboard, because it directs incoming sensory messages (with the exception of smell) to their proper place in the brain?
thalamus
James Old and Peter Milner discovered:
that the hypothalamus is a brain center that provides pleasurable rewards
cerebellum
the "little brain" at the rear of the brainstem; functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory
thomas fell and hit his head, so his parents brought him to the emergency room. explain how the following scars would give doctors different information about the type of injury thomas may have. CT scan MRI fMRI
the CT scan would reveal brain damage to structures that would be visible on an X-ray. the MRI would provide a much more detailed picture of the brain than a CT scan. the fMRI would enable the doctors to determine if the functioning of parts of the brain had been damaged, by looking at blood flow to certain regions.
the dual functions of the autonomic nervous system:
the autonomic nervous system controls the more autonomous (or self-regulating) internal functions. its sympathetic division arouses and expends energy. its parasympathetic division calms and conserves energy, allowing routine maintenance activity. for example, sympathetic stimulation accelerates heartbeat, whereas parasympathetic stimulation slows it.
medulla
the base of the brainstem; controls heartbeat and breathing
endocrine system
the body's "slow" chemical communication system; a set of glands that secrete hormones into the bloodstream
the hypothalamus helps keep:
the body's internal environment in a steady state
nervous system
the body's speedy electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems
central nervous system (CNS)
the brain and spinal cord
thalamus
the brain's sensory control center, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla
the brainstem and thalamus:
the brainstem, including the pons and medulla, is an extension of the spinal cord. the thalamus is attached to the top of the brainstem. the reticular formation passes through both structures.
are these older brain functions conscious or unconscious?
these older brain functions all occur without any conscious effort. our brain processes most information outside of our awareness. we are aware of the results of our brain's labor but not how we construct it.
what structures make up the brainstem, and what are the functions of the brainstem, thalamus, reticular formation, and cerebellum?
the brainstem, the oldest part of the brain, is responsible for automatic survival functions. its components are the medulla (which controls heartbeat and breathing), the pons (which helps coordinate movements), and the reticular formation (which filters incoming stimuli, relays information to other brain areas, and affects arousal). the thalamus, sitting above the brainstem, acts as the brain's sensory control center. the cerebellum, attached to the rear of the brainstem, coordinates muscle movement and balance and also helps process sensory information.
what are the functions of the nervous system's main divisions, and what are the three main types of neurons?
the central nervous system (CNS)--the brain and spinal cord--is the nervous system's decision maker. the peripheral nervous system (PNS), which connects the CNS to the rest of the body by means of nerves, gathers information and transmits CNS decisions to the rest of the body. the two main PNS divisions are the somatic nervous system (which enables voluntary control of the skeletal muscles) and the autonomic nervous system (which controls involuntary muscles and glands by means of its sympathetic and parasympathetic divisions). neurons cluster into working networks. there are three types of neurons: (1) sensory neurons carry incoming information from sense receptors to the brain and spinal cord. (2) motor neurons carry information from the brain and spinal cord out to the muscles and glands. (3) interneurons communicate within the brain and spinal cord and between sensory and motor neurons.
sympathetic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy
parasympathetic nervous system
the division of the autonomic nervous system that calms the body, conserving its energy
somatic nervous system
the division of the peripheral nervous system that controls the body's skeletal muscles. also called the skeletal nervous system
what is the nature and what are the functions of the endocrine system, and how does it interact with the nervous system?
the endocrine system is a set of glands that secrete hormones into the bloodstream, where they travel through the body and affect other tissues, including the brain. the adrenal glands, for example, release the hormones that trigger the fight-or-flight response. the endocrine system's master gland, the pituitary, influences hormone release by other glands. in an intricate feedback system, the brain's hypothalamus influences the pituitary gland, which influences other glands, which release hormones, which in turn influence the brain.
pituiary gland
the endocrine system's most influential gland. under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands
synapse
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron. the tiny gap at this junction is called the synaptic gap
threshold
the level of stimulation required to trigger a neural impulse
what are the limbic system's structures and functions?
the limbic system is linked to emotions, memory, and drives. its neural centers include the amygdala (involved in responses of aggression and fear); the hypothalamus (involved in various bodily maintenance functions, pleasurable rewards, and the control of the endocrine system); and the hippocampus (which processes conscious memories). the hypothalamus controls the pituitary (the "master gland") by stimulating it to trigger the release of hormones.
depolarization
the loss of the inside/outside charge difference
axon
the neuron extension that passes messages through its branches to other neurons or to muscles or glands
brainstem
the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions
cell body
the part of a neuron that contains the nucleus; the cell's life-support center
autonomic nervous system (ANS)
the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). its sympathetic division arouses; its parasympathetic division calms
following the release of neurotransmitters across the synapse, and an action potential, which of the following is most likely to take place?
the sending neuron reabsorbs the neurotransmitter for reuse
peripheral nervous system (PNS)
the sensory and motor neurons that connect the CNS to the rest of the body
what do phrenology and biological psychology have in common?
they share a focus on the links between the brain and behavior. phrenology faded because it had no scientific basis--skull bumps don't reveal mental traits and abilities.
the limbic system:
this neural system sits between the brain's older parts and its cerebral hemispheres. the limbic system's hypothalamus controls the nearby pituitary gland.
lesion
tissue destruction; a brain lesion is a naturally or experimentally caused destruction of brain tissue
how do PETs work?
tracks where a temporarily radioactive form of glucose goes while the brain of the person given it performs a given task
the role of the interneurons is to:
transmit and process information within the brain and spinal cord
amygdala
two lima-bean-sized neural clusters in the limbic system; linked to emotion
cerebral cortex
ultimate control and information-processing center
what does the cerebral cortex do?
ultimate control and information-processing center
how do nerve cells communicate with other nerve cells?
when action potentials reach the end of an axon (the axon terminals), they stimulate the release of neurotransmitters. these chemical messengers carry a message from the sending neuron across a synapse to receptor sites on a receiving neuron. the sending neuron, in a process called reuptake, then reabsorbs the excess neurotransmitter molecules in the synaptic gap. if incoming signals are strong enough, the receiving neuron generates its own action potential and relays the message to other cells.
what happens if you injur you cerebellum?
you would have difficulty walking, keeping your balance, or shaking hands. you movements would be jerky and exaggerated.
how does information flow through your nervous system as you pick up a fork?
your CNS' hungry brain activates and guides the muscles of your arm and hand via your peripheral nervous system's motor neurons. as you pick up the fork, your brain processes the information from your sensory nervous system, enabling it to continue to guide the fork to your mouth. the functional circle starts with sensory input, continues with interneuron processing by the central nervous system, and finishes with motor output.