lesson 4 and 5

Question 1

neuronal junction
the site of transmission of electric nerve impulses between two nerve cells (neurons) or between a neuron and a gland or muscle cell (effector).
it is a specialized gap between neurons

Answer 1

SYNAPSE

Question 2

anatomically demonstrated a narrow gap separating a neuron from another neuron

Answer 2

Ramon y Cajal

Question 3

introduced the term SYNAPSE

Answer 3

Charles Scott Sherrington

Question 4

-automatic muscular responses to stimuli.
-action that your body does in response to something — without you even having to think about .

Answer 4

Reflexes

Question 5

• The circuit from sensory neuron to muscle response
• neurological and sensory mechanism that controls a reflex, an immediate response to a particular stimulus.

Answer 5

Reflex Arc

Question 6

The simplest arrangement of a reflex arc consists of the___________; together, these units form a functional group.

Answer 6

receptor, an interneuron (or adjustor), and an effector

Question 7

the speed of conduction through the reflex arc varied but was never more than about 15 meters per second (m/s). In contrast, previous research had measured action potential velocities along sensory or motor nerves at about 40 m/s.

Sherrington concluded that some process was
slowing conduction through the reflex, and he inferred that the delay must occur where one neuron communicates with another

Answer 7

Speed of a reflex and delayed transmission of a response

Question 8

• is a phenomenon in which repeated stimuli within a brief time creates cumulative effect
• Temporal summation occurs when a series of subthreshold EPSPs in one excitatory fiber produce an AP in the postsynaptic cell

Answer 8

Temporal Summation (Summation over time)

Question 9

• Synaptic inputs from separate locations combine their effects on a neuron.
• ________ is critical to brain functioning. Sensory input to the brain arrives at synapses that individually produce weak effects. However, each neuron receives many incoming axons, which are synchronized during sensory stimulation (Bruno & Sakmann, 2006). Spatial summation assures that a sensory stimulus will stimulate the cortical cells enough to activate them

Answer 9

Spatial Summation (Summation over space)

Question 10

The bulk of the brain’s neurons are_________ — when they fire, they activate other neurons and propagate electrical signals throughout the brain. Inhibitory neurons do the opposite. The volley of chemical messages restrain, or inhibit, other neurons, making them less likely to fire messages of their own

Answer 10

excitatory

Question 11

_____ also allows neurons to synchronize their firing, giving rise to rhythmic oscillations of activity, or brain waves.

Answer 11

Inhibition

Question 12

In 1921, _____ devised a classical experiment, the outline of which came to him in several dreams. He awoke on the night of Easter Saturday in 1921 and wrote a few notes on a scrap of paper. To his horror, the next morning he could not decipher his own scrawl. He spent the rest of Easter Sunday in a desperate and unsuccessful attempt to reconstruct his dream. He was finally able to fall asleep that night, and he again dreamt of an epochal experiment. He again awoke from his dream, but this time he trusted his handwriting. He immediately repaired to his laboratory and conducted the experiment that had come to him in his dream, which he finished by the end of Easter Monday.

Answer 12

Otto Loewi

Question 13

acids containing an amine group (NH2)

Answer 13

Amino acids

Question 14

chains of amino acids

Answer 14

Neuropeptides

Question 15

(a one-member “family”) a chemical similar to an amino acid, except that the NH2 group has been replaced by an N(CH3)3group

Answer 15

Acetylcholine

Question 16

neurotransmitters containing one amine group (NH2), formed by a metabolic change in certain amino acids

Answer 16

monoamines

Question 17

a category of chemicals including adenosine and several of its derivativesgases nitric oxide and possibly others

Answer 17

purines

Question 18

—release of neurotransmitter in bursts from the presynaptic neuron into the synaptic cleft that separates this neuron from the postsynaptic neuron. An action potential often fails to release any transmitter, and even when it does, the amount varies

Answer 18

Exocytosis

Question 19

, a neurotransmitter attaches to a receptor that opens the gates to allow a particular ion, such as sodium, to cross the membrane more readily.

Answer 19

ionotropic synapses

Question 20

, a neurotransmitter activates a second messenger inside the postsynaptic cell, leading to slower but longer lasting changes. Neuropeptides diff use widely, affecting many neurons.

Answer 20

metabotropic synapses

Question 21

After a neurotransmitter (other than a neuropeptide) has activated its receptor, many of the transmitter molecules reenter the presynaptic cell through transporter molecules in the membrane. This process, known as

Answer 21

reuptake

Question 22

—receptors that detect the amount of transmitter released and inhibit further synthesis and release after it reaches a certain level. That is, they provide negative feedback (Kubista & Boehm, 2006).

Answer 22

autoreceptors

Question 23

transmits signals between the brain and the rest of the body, including internal organs.

It is your body’s command center

Answer 23

The nervous system

Question 24

2 main parts of the nervous system

Answer 24

central nervous system
peripheral nervous system

Question 25

is made up of the brain and spinal cord.

Answer 25

The central nervous system

Question 26

is made up of nerves that branch off from the spinal cord and extend to all parts of the body.

Answer 26

The peripheral nervous system

Question 27

consists of peripheral nerve fibers that carry sensory information or sensations from peripheral organs to the CNS. The ____ also includes motor nerve fibers that exit the brain to carry commands for movement to the skeletal muscles.

Answer 27

The somatic nervous system (SNS)

Question 28

controls the nerves of the body's inner organs that cannot be controlled consciously. The ___ can be further subdivided into the sympathetic, parasympathetic, and enteric nervous systems. Some of the different activities controlled by the ___ include the heartbeat, digestion, subconscious breathing, blood pressure, and sexual arousal.

Answer 28

The autonomic nervous system (ANS)

Question 29

Toward the back, away from the ventral (stomach) side. The top of the brain is considered dorsal because it has that position in four-legged animals.

Answer 29

Dorsal

Question 30

Toward the stomach, away from the dorsal (back) side

Answer 30

Ventral

Question 31

Toward the front end

Answer 31

Anterior

Question 32

Toward the rear end

Answer 32

Posterior

Question 33

Above another part

Answer 33

Superior

Question 34

Below another part

Answer 34

Inferior

Question 35

Toward the side, away from the midline

Answer 35

Lateral

Question 36

Toward the midline, away from the side

Answer 36

Medial

Question 37

Located close (approximate) to the point of origin or attachment

Answer 37

Proximal

Question 38

Located more distant from the point of origin or attachment

Answer 38

Distal

Question 39

On the same side of the body (e.g, two parts on the left or two on the right)

Answer 39

Ipsilateral

Question 40

On the opposite side of the body (one on the left and one on the right)

Answer 40

Contralateral

Question 41

A plane that shows brain structures as seen from the front (or frontal plane)

Answer 41

Coronal plane

Question 42

A plane that shows brain structures as seen from the side

Answer 42

Sagittal plane

Question 43

A plane that shows brain structures as seen from above (or transverse plane)

Answer 43

Horizontal plane

Question 44

________________ consists of neurons that receive information from and send commands to the heart, intestines, and other organs.

Answer 44

The autonomic nervous system

Question 45

2 parts of the autonomic nervous system

Answer 45

the sympathetic and parasympathetic nervous system

Question 46

It prepares the organs for vigorous activity, consists of chains of ganglia just to the left and right of the spinal cord’s central regions (the thoracic and lumbar areas). These ganglia are connected by axons to the spinal cord. Sympathetic axons prepare the organs for “fight or flight”—increasing breathing and heart rate and decreasing digestive activity

Answer 46

The Sympathetic

Question 47

It facilitates vegetative, nonemergency responses. The term para means “beside” or “related to,” and parasympathetic activities are related to, and generally the opposite of, sympathetic activities. For example, the sympathetic nervous system increases heart rate, but the parasympathetic nervous system decreases it.The parasympathetic nervous system increases digestive activity, whereas the sympathetic nervous system decreases it. Although the sympathetic and parasympathetic systems act in opposition, both are constantly active to varying degrees, and many stimuli arouse parts of both systems

Answer 47

The Parasympathetic/craniosacral system

Question 48

_______, the posterior part of the brain, consists of the medulla, the pons, and the cerebellum. Th e medulla and pons, the midbrain, and certain central structures of the forebrain constitute the brainstem

Answer 48

The hindbrain

Question 49

cranial nerves

Answer 49

I. Olfactory II. Optic II. Oculomotor IV. Trochlear V. Trigeminal VI. Abducens VIl. Facial VIll. Statoacoustic IX. Glossopharynge X. Vagus XI. Accessory XII. Hypoglossal

Question 50

I. Olfactory

Answer 50

Smell

Question 51

II. Optic

Answer 51

Vision

Question 52

III. Oculomotor

Answer 52

Control of eye movements; pupil constriction

Question 53

IV. Trochlear

Answer 53

Control of eye movements

Question 54

V. Trigeminal

Answer 54

Skin sensations from most of the face; control of jaw muscles for chewing and swallowing

Question 55

VI. Abducens

Answer 55

Control of eye movements

Question 56

VIl. Facial

Answer 56

Taste from the anterior two thirds of the tongue; control of facial expressions, crying, salivation, and dilation of the head's blood vessels

Question 57

VIll. Statoacoustic

Answer 57

Hearing; equilibrium

Question 58

IX. Glossopharynge

Answer 58

Taste and other sensations from throat and posterior third of the tongue; control of swallowing, salivation, throat movements during speech

Question 59

X. Vagus

Answer 59

Sensations from neck and thorax; control of throat, esophagus, and larynx; parasympathetic nerves to stomach, intestines, and other organs

Question 60

XI. Accessory

Answer 60

Control of neck and shoulder movements

Question 61

XII. Hypoglossal

Answer 61

Control of muscles of the tongue

Question 62

_________ is in the middle of the brain The topmost part of the brainstem, the connection central between the brain and the spinal cord. There are three main parts of the midbrain - the colliculi, the tegmentum, and tectum

Answer 62

The midbrain

Question 63

_________ is the most anterior and most prominent part of the mammalian brain. It consists of two cerebral hemispheres (left and right hemispheres) Each hemisphere is organized to receive sensory information, mostly from the contralateral (opposite) side of the body, and to control muscles, mostly on the contralateral side, by way of axons to the spinal cord and the cranial nerve nuclei

Answer 63

The forebrain

Question 64

________ of the brain are a communicating network of cavities filled with cerebrospinal fluid (CSF) and located within the brain parenchyma.

Answer 64

The ventricles

Question 65

___________ cushions the brain against mechanical shock when the head moves. It also provides buoyancy. Just as a person weighs less in water than on land, cerebrospinal fluid helps support the weight of the brain. It also provides a reservoir of hormones and nutrition for the brain and spinal cord.

Answer 65

Cerebrospinal fluid

Question 66

The ___________ (from a Latin word meaning “seahorse,” a shape suggested by the _________) is a large structure between the thalamus and the cerebral cortex. The gist of that discussion is that the ___________ is critical for storing certain kinds of memories. People with hippocampal damage have trouble storing new memories, but they do not lose the memories they had before the damage occurred

Answer 66

hippocampus

Question 67

Several structures lie on the ventral surface of the forebrain, including the nucleus basalis, which receives input from the hypothalamus and basal ganglia and sends axons that release acetylcholine to widespread areas in the cerebral cortex The nucleus basalis is a key part of the brain’s system fors. Patients with Parkinson’s disease and Alzheimer’s disease have impairments of attention and intellect because of inactivity or deterioration of their nucleus basalis.

Answer 67

Basal Ganglia

Question 68

__________is an endocrine (hormone-producing) gland attached to the base of the hypothalamus by a stalk that contains neurons, blood vessels, and connective tissue In response to messages from the hypothalamus, the pituitary synthesizes and releases hormones into the bloodstream, which carries them to other organs.

Answer 68

pituitary gland

Question 69

a structure deep in your brain, acts as your body's smart control coordinating center. Its main function is to keep your body in a stable state called homeostasis. It does its job by directly influencing your autonomic nervous system or by managing hormones.

Answer 69

hypothalamus

Question 70

It is a pair of structures (left and right) in the center of the forebrain. The term is derived from a Greek word meaning “anteroom,” “inner chamber,” or “bridal bed.” Most sensory information goes first to the thalamus, which processes it and sends output to the cerebral cortex. An exception to this rule is olfactory information, which progresses from the olfactory receptors to the olfactory bulbs and then directly to the cerebral cortex

Answer 70

Thalamus

Question 71

– outer portion of the forebrain

Answer 71

Cerebral Cortex

Question 72

- intermediate level of the midbrain; covers several other midbrain structures, although it is covered by the tectum; nuclei for the third and fourth cranial nerves, parts of the reticular formation, and extensions of the pathways between the forebrain and the spinal cord or hindbrain.

Answer 72

Tegmentum

Question 73

– the roof of the midbrain

Answer 73

Tectum

Question 74

The _________is a large hindbrain structure with many deep folds. It has long been known for its contributions to the control of movement, and many older textbooks describe the cerebellum as important for “balance and coordination.”

Answer 74

cerebellum

Question 75

- the swellings on each side of the tectum; both are important for sensory processing

Answer 75

Superior and inferior colliculus

Question 76

colliculus for hearing

Answer 76

the inferior colliculus

Question 77

colliculus that is mainly for vision

Answer 77

superior colliculus

Question 78

lies anterior and ventral to the medulla; like the medulla, it contains nuclei for several cranial nerves. Theterm pons is Latin for “bridge”; the name reflects the fact that many axons in the pons cross from one side of the brain to the other. Th is is in fact the location where axons from each half of the brain cross to the opposite side of the spinal cord so that the left hemisphere controls the muscles of the right side of the body and the right hemisphere controls the left side.

Answer 78

pons