A&P: The Nervous System

coordinates, consciousness, personalities, learn, memorize

The **nervous system** ______________ several activities in the body. It governs people’s ______________, their ______________, how they _______, and their ability to ______________.

central nervous system (CNS) and peripheral nervous system (PNS)

The nervous system is anatomically divided into two parts:

brain, spinal cord, information processing and control

**Central nervous system (CNS):** The central nervous system is comprised of the _______ and ______________. It is where ___________________________________ occurs.

nerves, CNS

**Peripheral nervous system (PNS):** The peripheral nervous system is comprised of the _________ associated with the CNS. It connects all nerves of the body to the ______.

afferent fibers, efferent fibers

There are two types of fibers in the PNS: (a) ______________ that transmit impulses from organs and tissues of the body to the CNS; and (b) ________________ that transmit impulses from the CNS to the organs and tissues of the body.

somatic, autonomic

The PNS is further divided into the _____________ and _____________ nervous systems.

voluntary, walking, riding a bicycle, motor nerve fibers, skeletal muscle

The **somatic nervous system** primarily controls __________ activities such as __________ and _________________. Thus, this system sends information to the CNS and_________________ that are attached to _______________.

non-voluntary, unconscious, glands, smooth muscles, heart rate, breathing, digestion

The **autonomic nervous system** is responsible for activities that are _______________ and under _______________ control. Because this system controls ________ and the _______________ of internal organs, it governs activities ranging from ________ to ________ and ________. 

Sympathetic nervous system and parasympathetic nervous system

The autonomic nervous system is further divided into the following:

emergency, fight or flight

**Sympathetic nervous system:** The sympathetic nervous system focuses on __________________ situations by preparing the body for __________________.

unrelated to, rest or digest

**Parasympathetic nervous system:** The parasympathetic nervous system controls involuntarily processes ______________ emergencies. This system deals with “________________” activities.

sensory, integrative, motor

Based on the activities of the nervous system, this system can be functionally divided into three parts:

gathered, internally, externally, sensory

**Sensory:** Information is ___________ (both ___________ and ___________) and carried to the CNS. The senses gather the information that the ___________ nervous system transmits.

process, interprets

**Integrative:** The integrative nervous system is where the CNS ___________ and ___________ information received from the sensory nerves.

convey, muscles, glands

**Motor:** Motor nerves _________ information that is processed by the CNS to _________ and _________.

neurons

The brain is a mass of tissue that is made of billions of nerve cells called __________.

five senses

This complex organ controls a wide range of processes and integrates information received from the ______________.

ventricles

Protected by the skull, the brain consists of four cavities called **_____________**.

cerebrospinal fluid (CSF)

These cavities are filled with **___________________________**, which surrounds the CNS.

protecting, physical shocks, removing wastes

The **cerebrospinal fluid** serves many purposes such as ____________ the brain from ___________________ and ______________________ from the neural tissue in the brain.

cerebellum, brainstem, cerebrum

The brain is divided into the following three regions:

beneath, behind, movements, posture, balance

**Cerebellum:** This is found ___________ the cerebrum and __________ the brainstem. It helps coordinate body _____________, _____________, and _____________.

thalamus, spinal cord, lowest, unconscious, breathing, heart rate, blood pressure

**Brainstem:** This is found between the _______________ and _______________. It is the __________ part of the brain that connects the brain with the spinal cord. _______________ functions like ____________, ____________, and ____________ are controlled by the brainstem.

largest, forebrain, higher-order functions, language, reasoning, fine motor control

**Cerebrum:** This part of the brain is the __________ and part of the __________. The cerebrum controls ____________________ such as interpreting touch, speech and __________, __________, emotions, and _________________.

cerebral cortex, grey (gray) matter, hemisphere

The **___________________** is **___________________** that surrounds the entire cerebrum. It is divided into a left and right _____________.

gyri, sulci

The ridges of the cerebral cortex are called **______**, and the grooves are called **______**.

fissures

The very large grooves are called **__________**.

frontal, parietal, temporal, and occipital lobe

The cerebral cortex is divided into four lobes:

cerebral cortex

The __________________ is the most complex part of the brain.

high-level cognitive skills, reasoning, concentration, emotions

**Frontal lobe**: Processes ___________________________, _____________, _____________, motor skills, language, and functions as a control center for ___________.

visual perception, sensory information

**Parietal lobe:** Integration site for _______________ and __________________ such as touch, pain, and pressure.

sounds, language, memories, speech perception, language skills

**Temporal lobe:** Organizes _________ and processes _________ that is heard. Helps form _________, ________________, and _______________.

visual stimuli

**Occipital lobe:** Interprets ________________ and information.

sensory neurons, motor neurons, interneurons

Grey matter is a type of neural tissue that contains three types of **neurons:**

afferent, five senses, external

**Sensory neurons:** ____________ nerve cells that send information toward the CNS. This information is what is sensed, using the ____________, from the ____________ environment.

efferent, impulses away, tissues, muscles

**Motor neurons:** _____________ nerve cells that carry _____________ from the CNS to the effectors, which are typically ___________ and ___________ of the body.

bridge, motor, sensory, neural circuit, communicate

**Interneurons:** Nerve cells that act as a _________ between _________ and _________ neurons in the CNS. These neurons help form _________, which helps neurons _________ with each other.

spinal cord, bundles of interneurons

 **White matter** is found in the _____________ and surrounds the grey matter. It contains _______________________.

limbic system

Another part of the forebrain incudes the **_______________**, which controls *emotions* and *memory*.

beneath, cerebral cortex, above, brainstem

The **limbic system** is found right __________ the __________________ and sits ________ the _____________.

hypothalamus, amygdala, thalamus, hippocampus

Four major structures of the brain comprise the limbic system:

below, regulating, autonomic, homeostasis, hunger, anger, pain, pituitary gland

**Hypothalamus:** Found ________ the thalamus, this structure plays a role in ________ the ________ nervous system. It is primarily concerned with ________ and regulates various activities such as ________, ________, and the response to ________. The hypothalamus works with the ________________ from the endocrine system. This gland uses hormones, or chemical messengers, to generate responses in the body.

aggression center, anger, violence, fear, anxiety

**Amygdala:** Recognized as the __________________, areas of this region produces feelings such as _______, _______, _______, and _______.

sensory inputs, smell, bypasses, movement

**Thalamus:** Different __________________ come through the nerves and end at the thalamus, which directs this information to various parts of the cerebral cortex. The sense of _______ is the only sense that _______ the thalamus. Information related to _______ is also processed by the thalamus.

short-term memory, long-term memory, cannot be formed, retained

**Hippocampus:** Helps convert ________________ to ________________. If the hippocampus is destroyed, new memories ________________ but old memories are ___________.

Kluver-Bucy syndrome, erratic emotional, hypersexuality, compulsive eating

______________________ is a condition that includes destruction of the **amygdala**. This means a person will present with _____________________ behavior symptoms like _____________________, ____________________, and putting objects in the mouth.

quickly send and receive messages

A large network of neurons work together to ______________________________________ throughout the body.

electric, chemical

A neuron’s structure is designed to transmit ____________ signals before they are transmitted as ____________ signals to a target cell. 

cell body, dendrites, axon

The following three basic parts make up a single nerve cell:

nucleus, soma, organelles

**Cell body:** This is the main part of the neuron that contains the ____________ of the nerve cell. Also called the _________, other _________ are also found in the cell body.

appendages, receive signals

**Dendrites:** These are ____________ attached to the cell body that ____________ from other neurons.

long structure, axon terminals, facilitate communication

**Axon:** This is the ___________________ attached to the cell body. It *conducts* and *transmits* information to other cells. Branches at the end of the axon form ___________________. These branches ___________________ between neurons and target cells.

nerve impulses, support, protect

**Neuroglial cells** do not conduct ________________ like neurons. Rather, they provide ___________ and ___________ neurons. 

astrocytes, microglial cell, oligodendrocytes, ependymal

Four major types of neuroglial cells in the CNS:

Schwann and satellite cells

Major types of neuroglial cells in the PNS:

protein, lipid, Schwann cell

The myelin sheath is a __________ and __________ structure produced by a type of __glial__ cell called a **__________** .

Myelin sheath, insulation, speed

___________________: This sheath functions like a blanket that provides a layer of ____________ around the axon of a neuron, increasing the _________ of electrical signal transmission.

nodes of Ranvier

 Regularly spaced gaps called ___________________ are found between the myleinated sheaths.

one node to the next

Electric signals jump from __________________________, thereby increasing the speed of signal transmission.

demyelination, multiple sclerosis

Several diseases cause degeneration of the myelin sheath, or **__________________**. One example is __________________.

motor and cognitive

When demyelination occurs, it can lead to severe neurological problems like ________________________ function.

reduces the speed, axon

Demyelination _________________________ at which neural impulses are transmitted along the _______.

excited

Neurons must be _____________ to create a nerve impulse.

stimulus

A _____________ triggers excitation.

inside, negatively charged, outside, positively charged, potassium, sodium

At the resting state, the ________ of the neuron is more ________________, while the ________ of the neuron is more ________________. This difference in electrical charge because of ________ and ________ ions establishes the **resting potential**.

neuroplasticity, synapses

As a person ages, the rate of **__________________**, or ability for the brain to form neural connections through ____________, decreases.

new stimulation, damage, changes

**Neuroplasticity** is important because it helps the brain adapt to _____________, _____________, or _____________ in the environment.

reverse, electrical charge, axon, electric current

During the **action potential**, a __________ in ________________ occurs across the membrane of a neuron in its resting state. This reverse in charge travels down the _______ as an ______________.

1, 4, 7, 2, 3, 6, 5

1. Once the action potential reaches the terminal bulbs of the axon terminal, the synaptic transmission process begins. 
2. Calcium ions bind with proteins on synaptic vesicles that carry chemical messages called **neurotransmitters**.
3. This binding causes the vesicles to contract and move to the presynaptic membrane.
4. Voltage gated Ca2+ channels open at the same time.
5. Neurotransmitters bind with receptors on the postsynaptic membrane of a neuron, gland, or muscle.
6. Neurotransmitters are released from the vesicles via exocytosis and diffuse across the **synaptic cleft**.
7. Calcium ions move into the axon terminal bulb of the presynaptic neuron.

terminal branches, voltage gated sodium, bulb

An action potential travels down the axon and reaches the _________________ of the axon. ____________________ gates open, causing sodium to enter the axon terminal _______.

presynaptic

Calcium ions move into the axon terminal bulb of the _____________ neuron.

neurotransmitter

Calcium ions bind with proteins on synaptic vesicles that carry chemical messages called **_____________________**.

exocytosis, synaptic cleft

Neurotransmitters are released from the vesicles via ______________ and diffuse across the **______________**.

postsynaptic, neuron, gland, muscle

Neurotransmitters bind with receptors on the _______________ membrane of a _______, _______, or _______.

Nervous system

1

Peripheral nervous system

2

Central nervous system

3

Somatic nervous system

4

Autonomic nervous system

5

Sympathetic nervous system

6

Parasympathetic nervous system

7

Frontal lobe

1

Central sulcus

2

Parietal lobe

3

Gyri

4

Occipital lobe

5

Cerebellum

6

Spinal cord

7

Medulla oblongata

8

Pons

9

Temporal lobe

10

Lateral sulcus

11

Hypothalamus

1

Thalamus

2

Hippocampus

3

Amygdala

4

Dendrite

1

Axon

2

Node of Ranvier

3

Axon terminal

4