Nervous System Flashcards
What is the primary function of the nervous system?
The body’s control and communication centre, detects stimuli, processes sensory information, and sends signals to muscles and glands to trigger responses.
What are the two main components of the nervous system?
Central Nervous System (CNS) and Peripheral Nervous System (PNS)
What are the two main parts of the Central Nervous System (CNS)?
Brain and Spinal Cord
What is the role of the brain?
Controls thought, memory, emotions, and decision-making.
What is the function of the spinal cord?
Relays messages between the brain and the body, controlling reflexes.
What is the function of sensory neurons in the Peripheral Nervous System (PNS)?
Transmit signals from sensory receptors to the CNS.
What do motor neurons do?
Carry instructions from the CNS to muscles and glands.
What are neurons?
Specialized cells that transmit electrical and chemical signals in the body, enabling communication with the nervous system.
What does the cell body (soma) of a neuron contain?
The nucleus and controls the cell’s activities.
What are dendrites?
Branch-like extensions that receive signals from other neurons and send them to the cell body.
What is the function of the axon?
A long, thin projection that carries electrical signals away from the cell body to other neurons, muscles, or glands.
What is the myelin sheath?
A fatty layer that surrounds the axon, speeding up the transmission of signals.
What is a synapse?
The junction between two neurons where chemical signals (neurotransmitters) are passed to the next cell.
What are the types of neurons?
- Sensory: Carry information from sensory receptors to the CNS.
- Motor: Transmit signals from the CNS to muscles and glands.
- Interneurons: Connect neurons within the CNS.
How does an electrical signal travel through a neuron?
An electrical impulse (action potential) travels down the axon to the axon terminal.
What triggers the release of neurotransmitters at the synapse?
The electrical signal at the synapse.
What happens to neurotransmitters after they are released?
They cross the synaptic gap and bind to receptors on the neighboring neuron’s dendrites or target cell.
What are excitatory synapses?
Synapses that encourage the receiving neuron to generate a signal, promoting action.
What are inhibitory synapses?
Synapses that prevent the receiving neuron from firing, reducing activity.
Name three examples of neurotransmitters.
- Dopamine
- Serotonin
- Acetylcholine
What functions does the Central Nervous System (CNS) regulate?
- Voluntary activities (e.g., movement)
- Involuntary functions (e.g., breathing, heart rate)
What is the role of the CNS in processing information?
Integrates sensory data and determines responses.
What is a reflex action?
An automatic response controlled by the spinal cord without involving the brain.
What cognitive functions are managed by the CNS?
- Memory
- Problem-solving
- Decision-making
- Emotional responses
What is the control center of the nervous system?
The brain
What does the spinal cord do?
Relays messages between the brain and the rest of the body.
What is the primary organ of the NCS responsible for information processing?
The brain
NCS stands for Nervous System.
What are the cognitive functions of the brain?
Controls thinking, reasoning, problem-solving, decision making, regulates memory and learning.
What is the emotional function of the brain?
Processes emotions, manages stress responses and mood.
What does the brain do for movement and coordination?
Sends signals to muscles to control voluntary movements, cerebellum helps with coordination and balance.
How does the brain handle sensory information?
Intercepts input from the senses (sight, sound, touch) to help understand and react to the environment.
What automatic body functions does the brain regulate?
Breathing, heartbeat, digestion through the brain stem.
What roles does the brain play in speech and communication?
Controls speech production, language understanding, communication abilities.
What is the largest part of the brain responsible for higher brain functions?
Cerebrum.
What are the functions of the left hemisphere of the cerebrum?
Logical thinking, language, analytical skills.
What are the functions of the right hemisphere of the cerebrum?
Creativity, intuition, spatial abilities.
What is the role of the cerebellum?
Coordinates movement and maintains balance and posture.
What does the brainstem connect?
Connects the brain to the spinal cord.
What essential functions does the brainstem control?
Breathing, heartbeat, digestion, reflexes.
What is the spinal cord?
Long thin bundle of nerve fibers extending from the brainstem down the spine.
What are the three protective layers surrounding the brain and spinal cord?
Dura mater, arachnoid mater, pia mater.
What is the function of the dura mater?
Tough outermost layer, protects against injury.
What is the role of the arachnoid mater?
Middle web-like layer, provides cushioning, holds cerebrospinal fluid (CSF).
What is the function of the pia mater?
Delicate innermost layer, nourishes the brain and spinal cord with blood supply.
Where is cerebrospinal fluid (CSF) found?
In the space between arachnoid and pia mater (subarachnoid space).
What is the role of cerebrospinal fluid (CSF)?
Acts as cushioning, protecting CNS from injury and providing nutrients.
What does the Peripheral Nervous System (PNS) consist of?
All the nerves that lie outside the brain and spinal cord.
What is the function of the Autonomic Nervous System?
Controls involuntary physiological functions, operates automatically.
What does the sympathetic nervous system do?
Increases heart rate and blood pressure, dilates pupils, relaxes airway.
What does the parasympathetic nervous system do?
Calms body, conserves energy, decreases heart rate and blood pressure.
What is the Somatic Nervous System responsible for?
Controlling voluntary movements and processing sensory information.
What do motor neurons do?
Carry commands from CNS to skeletal muscles for voluntary movements.
What do sensory neurons do?
Relay sensory information from body to CNS.
What are sense organs?
Specialized structures that receive and process information from the environment.
What is the function of the eyes?
Detect light and color, allowing us to see and interpret visual information.
How does light enter the eye?
Through the cornea.
What is the role of the lens in the eye?
Adjusts shape to focus light on the retina.
What converts light into electrical signals in the eye?
Photoreceptors in the retina.
What are rods and cones in the retina responsible for?
- Rods: low-light vision
- Cones: color vision.
What is the pathway of electrical signals from the retina?
Sent via the optic nerve to the visual cortex in the brain.
What is the function of the outer ear?
Collects sound waves, channels them to the eardrum.
What happens when sound waves hit the eardrum?
Causes it to vibrate.
What are the ossicles in the middle ear?
Three tiny bones: malleus, incus, stapes.
What does the cochlea do?
Contains hair cells that convert vibrations into electrical signals.
How are electrical signals from the inner ear transmitted?
Via the auditory nerve to the auditory cortex in the brain.
