6) Muscle & Nerve Flashcards
How do smooth and skeletal muscles differ in terms of control?
Smooth muscle: Involuntary control.
Skeletal muscle: Voluntary control.
What is the function of muscle tissue?
Produces movement.
What are key features of muscle tissue?
Highly vascularized
Derived from mesoderm
Contains numerous mitochondria for energy
Contains contractile proteins (actin & myosin)
Only striated muscles have a regular arrangement of actin and myosin
What are the three types of muscle?
Skeletal (voluntary), cardiac (involuntary), and smooth (involuntary).
What controls muscle activity?
Chemical and mechanical forces regulated by the nervous system.
Describe the structure of skeletal muscle.
STRAITED VOLUNTARY
Long, cylindrical, multinucleated cells on the periphery, highly vascularized, striated, no cell division.
What is the function of skeletal muscle?
Voluntary movement, manipulation of the environment, facial expressions, and heat generation.
Where is skeletal muscle found?
Attached to bones and occasionally to skin.
Describe the structure of cardiac muscle.
STRAITED INVOLUNTARY)
Branched fibers, 1-2 central nuclei, collagen between fibers, rich capillary network, intercalated discs.
What is the function of cardiac muscle?
Pumps blood.
Where is cardiac muscle located?
Myocardium of the heart.
What is the role of intercalated discs?
Attach fibers and facilitate rapid spread of contractile stimuli.
Describe the structure of smooth muscle.
Non-Striated, Involuntary
Non-branching, single central nuclei, arranged in sheets, no striations, capable of division.
What is the function of smooth muscle?
Moves substances through organs.
Where is smooth muscle located?
Walls of blood vessels, hollow organs, and viscera.
Q: What is the function of nervous tissue?
Conducts electrical impulses and relays information.
Q: Where is nervous tissue found?
A: Brain, spinal cord, and nerves.
Q: What are the two types of cells in nervous tissue?
Neurons (excitable cells).
Neuroglia (supporting cells).
Q: What are the components of a neuron?
A: Soma (cell body), dendrites (receive information), and axon (transmits information).
Can neurons regenerate?
A: No, neurons do not regenerate after death but may regenerate after damage if the cell body is viable.
CNS consists of
Cerebrum, cerebellum & spinal cord
PNS consists of
Spinal & cranial nerves, ganglia & sense organs autonomic nervous system
Q: What are the four types of CNS neuroglia and their functions?
Oligodendrocytes: Form myelin sheaths in the CNS.
Astrocytes: Form the blood-brain barrier and provide structural support.
Ependymal Cells: Line the central canal and ventricles; involved in CSF formation.
Microglia: Act as macrophages, aiding immune defense.
Q: What are the regions of the CNS based on myelin distribution?
White matter: Myelinated axons, lacks cell bodies.
Grey matter: Contains neuron cell bodies, dendrites, and glial cells.
Q: What is the primary function of the cerebrum?
A: Responsible for higher neurological functions like memory, emotion, and consciousness.
Q: What is the structure of the cerebellum?
A: Grey matter forms convoluted folds (folia); coordinates muscular activity and posture.
Q: How is the spinal cord structured?
A: Grey matter inside (butterfly pattern), white matter outside.
Q: What does the PNS consist of?
A: Nerves, ganglia, and nerve endings.
Q: What is a ganglion?
A: A collection of neuron cell bodies in the PNS.
Q: What forms the myelin sheath in the PNS?
A: Schwann cells.
Q: Name a few diseases affecting the nervous system.
Stroke: Blockage or bleeding of brain vessels.
Epilepsy: Uncontrolled neuronal excitability.
Neurodegenerative Disorders: Alzheimer’s, Parkinson’s, motor neuron disease.
Demyelinating Diseases: Affects signal transmission.
