Download Introduction to the Nervous System Guided Notes are masses of

Introduction to the Nervous System Guided Notes
1. _________________ are masses of nerve cells that transmit information. All neurons contain three main
components: (1) _______ _______________ – contains the nucleus and two extensions, (2)
___________________ – shorter, more numerous, receive information, and (3) ____________ – single
long “fiber” which conducts impulse away from the cell body, sends information.
2. Speed of an impulse is proportionate to the
of the
diameter = faster speed. Myelinated Axons conduct faster than unmyelinated ones.
AXON.
Greater
3. Each synaptic terminal is part of a _________________, a specialized site where the neuron communicates with
another cell. Two cells meet at every synapse:
1) ___________________ cell – ___________ the message
2) ___________________ cell – _____________ the message
4.
Communication between cells at the synapse occurs by releasing chemicals called
_______________________________. Neurotransmitters are packaged in _______________________, and are released
by the presynaptic cell (neuron) and received by the postsynaptic cell (neuron, muscle, gland).
5. There are three basic functions of the nervous system.
(1) ___________________ – gathers information
(2) ______________________ – information is brought together
(3) _________________ – responds to signals to maintain homeostasis
6. There are two divisions of the nervous system:
(1) _________________ Nervous System (CNS) – includes ________________ and ______________ cord
(2) __________________ Nervous System (PNS) – includes _________________ of the body. This includes ____
pairs of spinal nerves and _____ pairs of cranial nerves
7. CNS neuroglial cells function as ___________________ cells for the neurons. There are four main types of neuroglial
cells found in the CNS:
(1) __________________ cells - Found scattered throughout the nervous system. _______________ numerous
and smallest neuroglia in the CNS. They function to _______________ debris or bacteria. Microglial cells respond
to immunological alarms!
(2) ___________________________ - Wraps around the axon, forming concentric layers of cell membrane called
__________________. This wrapping ______________________ the speed at which the action potential travels
along the axon.
(3) ______________________ - Astrocytes connect _____________ _______________ to the
___________________. They are the largest and most numerous neuroglia in the CNS. They are responsible for:
(1) Maintaining the ___________________________ barrier
(2) ___________________ damaged neural tissue
(3) Guide ________________ development
(4) ____________________ Cells - Ependymal cells form a __________________________ that lines the
ventricles (chambers) of the brain and the central canal of the spinal cord. They assist in producing, circulating,
and monitoring of ________________________ fluid.
8. Within the peripheral nervous system, there are two more systems responsible for motor functions:
(1) ____________________ Nervous System – controls skeletal muscle contractions (___________________) and
involuntary skeletal contractions like those seen in ___________________ (automatic response – put hand on hot
stove, remove it quickly)
(2) ____________________ Nervous System – provides ________________________ regulation of smooth
muscles, cardiac muscle, and glands (______________________)
10. There are three types of functional classifications:
(1) ________________ neurons - ______________________ neurons that make up the afferent component of
the PNS; deliver information from _____________________ receptors to the ___________.
(1) _________________________ – provide information about the external environment (touch,
temperature, pressure, sight, smell, hearing)
(2) ___________________________– monitor the position and movement of skeletal muscles and joints
(3) __________________________ – Monitor internal environment and provide sensations of taste, deep
pressure, and pain
(2) _____________ neurons - Efferent neurons that make up efferent component of the PNS; carry instructions
from the CNS to the peripheral effectors.
(1) ________________ motor neurons – innervate skeletal muscle (conscious control – Somatic Nervous
System)
(2) _____________ motor neurons – innervate all peripheral effectors except muscle (Autonomic
Nervous System)
(3) ______________________ - Most located in brain and spinal cord. These are responsible for the distribution
of _________________ information and the coordination of _______________ activity. They are also involved in
higher functions, such as ________________, planning, and ____________________.
11. Neurotransmitters can be:
- increase membrane permeability, make communication happen or
- decrease membrane permeability, stop communication from happening
12. Basic steps of an Action Potential:
1. Neuron is at _____________ potential (-70 mV)
2. Neurotransmitters bind to receptors on ____________________
3. Causes ____________ to rush into cell body
4. Membrane potential becomes more ________________ ( +30mV)
5. ________ channels close
6. ________________ rushes out of cell to balance out differences in membrane potential
7. Membrane potential goes to _____mV but then goes back to ______mV
8. Continues along length of ____________
9. Action Potential reaches axon terminal and ________ channel open
10. Ca2+ enters axon terminal and binds to __________________
11. Vesicles with neurotransmitters inside travel to end of axon ____________________
12. Vesicles release _______________________________ into synaptic cleft
13. Neurotransmitters travel through synaptic _____________ and bind to next ___________________
13.
= membranes located between bone and soft tissues of the nervous system
- outermost layer
- no blood vessels, in between layer (resembles a spider web)
-inner membrane, contains nerves and blood vessels to nourish cells
14. Spinal cord - Passes down the vertebral canal, has
These nerves branch to various body parts and connect them to the CNS.
(each with a pair of spinal nerves).
8 pairs of cervical nerves (C1 - C8)
12 pairs of thoracic nerves (T1-T12)
5 pairs of lumbar nerves (L1-L5)
5 pairs of sacral nerves (S1-S5)
1 pair of coccygeal nerves (Co)
15.
the
or lower.
disease affecting the
- Paralysis of the legs and lower body, typically caused by spinal injury or disease affecting
- Paralysis of all four limbs, typically caused by spinal injury or
.
16.
- fluid that protects and supports brain.
17. There are three major parts of the brain:
– largest, sensory and motor functions, higher mental function, reasoning, problem solving,
initiating simple voluntary muscular movements)
– coordinate voluntary muscles, controls posture, balance, and coordination.
– regulate visceral functions and reflexes. The brain stem has four parts:
1.
- includes the
and
glands.
Thalamus contains relay and processing centers for sensory information. Hypothalamus is
involved with emotions, autonomic function, and hormone production
2.
- is responsible for processing visual and auditory data. Generates
somatic reflex responses (EX: response to loud unexpected noises – head turning and eye
movement). Also responsible for
.
3.
- relays sensory information to the cerebellum and thalamus. Also
contains nuclei involved with somatic and visceral motor control.
4.
-
connects to the brain at the medulla
oblongata. Relays sensory information to the thalamus and other parts of the brain stem.
Regulates visceral functions = cardiovascular, respiratory, and digestive system
18.
- connects the two hemispheres
19.
- the wrinkles and grooves of the cerebrum.
Fissure –
Sulci –
Gyri –
20. Parietal –
Frontal –
, relation of body parts, Temporal –
.
21. Limbic System – Memory is controlled by the
plays a major role in memories. Amygdala fear response, pleasure and aggression.
, Occipital –
(“sea horse”; that’s its shape). The hippocampus
.~Also associated with