Nervous Control of Muscular Movement Flashcards
Lecture 11
What is the Central Nervous System (CNS)?
The CNS consists of the brain and spinal cord. It controls everything the body does.
What is the Peripheral Nervous System (PNS)?
everything BUT the brain and spinal cord
Afferent Sensory Division (PNS)
The afferent sensory division carries information from the body (e.g., skin, muscles) to the brain and spinal cord.
Efferent division
The efferent division sends commands from the brain and spinal cord to the body. It includes the somatic (voluntary) and autonomic (involuntary) systems.
The Brain (Anatomy) (7 minutes)
What is the Cerebral Cortex?
What is the Spinal Cord?
The spinal cord is a bundle of nerves that runs from the brainstem to the lumbar vertebrae, carrying messages to and from the brain.
What are the Meninges?
layers of tissue that protect the brain and spinal cord, similar to saran wrap.
What are Nerves?
Bundles of axons in the PNS that transmit sensory and motor information between the CNS and the body.
Include 12 pairs of cranial nerves and 31 pairs of spinal nerves.
What is the Sympathetic Nervous System?
The sympathetic nervous system controls the “fight or flight” response during stressful situations.
What is the Parasympathetic Nervous System?
The parasympathetic nervous system handles “rest and digest” functions when the body is relaxed.
What is Somatic Nervous System?
The part of the PNS associated with voluntary control of body movements via skeletal muscles.
What is Autonomic Nervous System?
A component of the PNS that regulates involuntary physiological functions, including heart rate, digestion, and respiratory rate.
What two types of categories of nerve cells should you know?
The two types of nerve cells are neurons (which send signals) and neuroglia (which support neurons).
Neuroglia
Neuroglia are non-excitable cells that support and keep neurons alive in the CNS and PNS.
Neuron
The fundamental unit of the nervous system, responsible for receiving, processing, and transmitting information through electrical and chemical signals.
What is the Basic Structure of a Nerve Cell?
Cell Body (soma): Keeps the cell alive.
Axon: Sends signals.
Dendrites: Receive signals.
Myelin Sheath: Covers axons to make signals faster.
Nodes of Ranvier: Gaps in the myelin sheath.
What is Saltatory Conduction?
Saltatory conduction is when signals jump between gaps in the myelin sheath (Nodes of Ranvier), making them faster.
What is multiple Scelorosis
A disease characterized by the immune system attacking the myelin sheath of neurons, leading to disrupted neural communication. This leads to symptoms like fatigue, muscle weakness, and coordination problems.
What is a Synapse?
The junction between two neurons or a neuron and a target cell, where communication occurs via neurotransmitters.
What are interneurons?
Interneurons connect sensory (afferent) and motor (efferent) neurons. They can increase, decrease, or reverse signals.
Spinal Nerves
Thirty-one pairs of nerves arising from the spinal cord, responsible for motor and sensory functions.
What happens if you don’t get Action Potentials
Without action potentials, your body can’t send signals. For example, tetrodotoxin from pufferfish can block sodium channels, preventing signals.
What is a Nerve to Nerve Synapse?
where signals are passed between neurons through a synaptic cleft.