Nervous System (6) Flashcards
1
Q
The NERVOUS SYSTEM (2)
A
- The nervous system is the body’s way of gathering information, storing it, and responding to it.
- Main role is to assemble information about conditions EXTERNAL and INTERNAL to the body.
→ Analyze this information
→ Initiate responses that may be necessary to satisfy certain needs.
2
Q
The BRAIN (3)
A
- Control center or “computer” of the body.
- Incapable of performing physical tasks therefore it sends commands to other parts of the body to perform them.
- 6 main parts: Cerebrum, cerebellum, brain stem, diencephalon, limbic system, and the reticular activation system.
3
Q
Properties of the CEREBRUM (3)
A
- Largest part of the brain
- Contains nerve centers that control sensory and motor activities.
- Can be divided into two halves or “hemispheres”
→ Each hemisphere is divided into 4 lobes named after the bone they lie over.
→ Frontal lobe, temporal lobe, parietal lobe, occipital lobe.
4
Q
Properties of the CEREBELLUM (3)
A
- Second largest region.
- Lies behind and below the cerebrum.
- Main function is to coordinate muscle movement and control balance.
5
Q
Properties of the BRAIN STEM (3)
A
- Below cerebrum and in front of the cerebellum.
- Links the cerebrum with the spinal cord.
- Houses brain centers responsible for automatic functions, postural control, muscle tone, and eye movement.
6
Q
Properties of the DIENCEPHALON (3)
A
- Consists of the thalamus and hypothalamus.
- THALAMUS: Relays most sensory stimuli to the cerebral cortex.
- HYPOTHALAMUS: Controls body temperature, appetite, emotions and various automatic functions.
7
Q
Properties of the LIMBIC SYSTEM (1)
A
- Composed of a collection of structures that regulate basic drives.
→ i.e Hunger, aggression, emotional drives.
8
Q
Properties of the RETICULAR ACTIVATING SYSTEM (4)
A
- Network of neurons.
- Fans out through the cerebral cortex.
- Directs information to appropriate centers for interpretation.
- Crucial for maintaining consciousness.
9
Q
What is the PERIPHERAL NERVOUS SYSTEM? (3)
A
- Carries information in and out of the CNS using 2 different kinds of nerves:
- MOTOR NERVES - aka efferent (outwards) nerves carry information from the CNS to the body’s organs.
- SENSORY NERVES - aka afferent (inwards) nerves carry information from sensory receptors to the CNS.
10
Q
Explain the AUTOMATIC NERVOUS SYSTEM (3)
A
- Subsystem of the PNS
- Controls involuntary actions (i.e heartbeat)
- Comprised of two branches that act as opposing systems:
→ SYMPATHETIC SYSTEM
→ PARASYMPATHETIC SYSTEM
11
Q
Explain the SYMPATHETIC SYSTEM (2)
A
- Causes localized bodily adjustments to occur (i.e sweating)
- Prepares the body for emergencies
→ Involves release of adrenaline, increase heart rate, widening blood vessels and “fight for flight” response.
12
Q
Explain the PARASYMPATHETIC SYSTEM (1)
A
- Helps the body return to normal after it has been altered by the sympathetic system.
→ Sympathetic system will increase heart rate, parasympathetic system will decrease heart rate to bring it back to its resting state.
13
Q
Explain the SOMATIC NERVOUS SYSTEM (4)
A
- Responsible for our awareness of the external environment.
- Through this system, the PNS receives and processes information from receptors in the skin, voluntary, muscles, tendons and joints.
- Gives sensation of touch, pain, heat, cold balance, body position and muscle action.
- Handles the muscles in our extremities which allows us to move.
14
Q
Introduction to the REFLEX ARC (3)
A
- Reflexes are an automatic and rapid response to a particular situation.
- If the command center for the reflex is located in the brain, it is called CEREBRAL REFLEX.
- If the command center of the reflex is located in the spinal cord, it is called SPINAL REFLEX.
15
Q
What are AUTONOMIC REFLEXES? (3)
A
- Controlled by the autonomic division of the nervous system.
- Involve activation of smooth and cardiac muscles (involuntary muscles).
- Regulates bodily functions such as digestion, elimination, blood pressure, salivation and sweating.