Exam 2 Flashcards
Synarthroses
Immovable Joint
Ampiarthroses
Semi-movable joint
Diarthroses/Synovial
Freely movable joint
Where are synovial joints located?
At the end of long bones such as femurs, tibias, humerus, and radius
Articular capsule
Joint capsule that surrounds synovial joints
What are synovial joints composed of ?
Synovial membrane, synovial fluid, and articular cartilage
Meniscus
Accessory structure of the knee joint
Functions of synovial fluid
Lubrication, nutrient distribution, and shock absorption
Functions of articular cartilage
Covers articulating surfaces and prevents direct contact between bones
Types of intervertebral joints
First two cervical vertebrae are joined by a synovial joint
Synovial joints lie between adjacent processes
Adjacent vertebral bodies form symphyses
Structure of anulus fibrosus
Tough outer layer of fibrocartilage
Function of anulus fibrosus
Attaches disc to vertebrae
Structure of nucleus pulposus
Elastic, gelatinous core
Function of nucleus pulposus
Absorbs shocks
Buldging discs
Bulge in anulus fibrosus that invades vertebral canal
Herniated discs
Nucleus pulposes breaks through anulus fibrosus and compresses spinal nerves
Location of ACL
Anterior tibia to posterior femur
Function of ACL
Keeps the tibia from moving forward
Location of PCL
Posterior tibia to anterior femur
Function of PCL
Keeps tibia from moving back
Which ligaments stabilize the knee joint?
Tibia collateral ligament (ACL) and fibular collateral ligament (MCL)
Classifications of menisci
Medial and lateral
What are the muscles of the rotator cuff?
Supraspinatus, infraspinatus, teres minor, subscapularis
What is arthritis?
All rheumatic diseases that affect synovial joints
Osteoarthritis
Caused by mechanical stresses of the joint surfaces
Rheumatoid arthritis
Immune system attacks joint tissue
Gouty arthritis
Crystals of uric acid form within synovial fluid
Neurons
Brain cell that sends an electrical impulse in one direction
Most common neuron?
Multipolar neuron
Pathway of an electrical impulse
Presynaptic cell -> synapse -> postsynaptic neuron
Location of neuroglia
Central nervous system and peripheral nervous system
Contents of central nervous system
Astrocytes, ependymal, oligodendrocytes, and microglia
Astrocytes
Maintain blood brain barrier, provides structural support, regulate ion, nutrient, and dissolved gas concentrations, absorb and recycle neurotransmitters, form scar tissue after injury
Ependymal cells
Line ventricles (brain) and central canal (spinal cord), assist in producing, circulating, and monitoring cerebrospinal fluid.
Oligodendrocytes
Myelinate central nervous system axons and provide structural framework
Microglia
Remove cell debris, waste, and pathogens by phagocytoses
Contents of the peripheral nervous system
Satellite cell and Schwann cells
Satellite cells
Surround neuron cell bodies in ganglia, regulate O2, CO2, nutrient, and neurotransmitter levels around neurons in ganglia
Schwann cells
Surround all axons in peripheral nervous system, responsible for myelination of peripheral axons, participate in repair process after injury
Location of CNS
Brain and spinal cord
Location of PNS
Nervous tissue outside of the CNS and ENS
Chemically gated ion channel
Opens in presence of ligand at a binding site
Voltage-gated ion channel
Opens with changes in membrane potential (-60 mV)
Mechanically gated ion channel
Opens in response to the distortion of the membrane
Polarization
Neuronal polarization establishes distinct molecular structures to generate a single axon and multiple dendrites.
Depolarization
An all-or-nothing event that is initiated by the opening of sodium ion channels within the plasma membrane. +30mV
Hyperpolarization
When the membrane potential becomes more negative at a particular spot on the neuron’s membrane
Graded potential vs action potential
The main difference between graded potential and action potential is that graded potentials are the variable-strength signals that can be transmitted over short distances whereas action potentials are large depolarizations that can be transmitted over long distances
What is the treshold?
The critical level to which a membrane potential must be depolarized to initiate an action potential. -55mV
Function of a dendrite
Recieves information
Cell body of a neuron
Processes and integrates information
Function of an axon
Carries the information along long distances
Function of an axon terminal
Transmits information to next cell in the chain
Where does continuous propagation occur?
Unmyelinated axons
Where does salutatory propagation occur?
Myelinated axons
How does myelin affect action potential?
Myelin makes it go faster
Where are the checkpoints?
Oligodendrocytes and Schwann cells
Size of type A fibers
Large diameters
Myelination status of type A fibers
Myelinated
Relative speed of type A fibers
Fast
Size of type B fibers
Small diameter
Myelination status of type B fibers
Myelinated
Relative speed of type B fibers
Medium
Size of type C fibers
Small diameter
Myelination status of type C fibers
Unmyelinated
Relative speed of type C fibers
Slow
Inhibitory neurotransmitters
Decreases the likelihood that the neuron will fire an action potential (GABA)
Excitatory neurotransmitters
Increases the likelihood that the neuron will fire an action potential (Glutamate)
What happens when acetyl choline is blocked?
Paralysis occurs
Types of spinal nerves
Cervical nerves, thoracic nerves, lumbar nerves, sacral nerves, and coccygeal nerves
Conus Medullaris
The tip of the spinal cord
Cauda Equina
Collection of spinal nerve roots coming off of the conus medullaris
What are the functional organs of grey matter?
Sensory nuclei and motor nuclei
Horns of grey matter
Posterior, lateral, and anterior
Layers of the spinal meninges
Dura, arachnoid, subarachnoid, and pia mater
Which layer of the meninges touches the brain?
Pia mater
What is subarachnoid space?
Filled with cerebral spinal fluid and blood vessels; extends down to filum terminale
Somatic motor neurons
Skeletal muscles
Autonomic motor neurons
Smooth muscles, cardiac muscles, glands, and adipose tissue
Somatic sensory neurons
Monitor the outside world and our position within it
Visceral sensory neurons
Monitor internal conditions (organs)
Describe pain fibers
Small, slow, and unmyelinated
Reflex arc
Sensory neurons sends information in