Muscle Overall Study Guide (copy)

For Anatomy Lab Practical

Skeletal Tissue

Tissue with voluntary movement; majority of the muscle in the body; striated

Smooth Tissue

Lines hallow organs; involuntary; not striated

Cardiac Tissue

In the heart; involuntary; striated

Muscle Fiber

single muscle cell; help control physical forces within the body

Myofibril

Functional units of a muscle; made up of think and thin myofilaments which give striated look

Myosin Filament

Protein molecule in muscle, Thick filament

Actin Filament

Protein muscle in muscle; thin; slide along with myosin filaments; has attatchment sites for myosin

Myofilament

Threads of myofibril

Contractile Proteins

Actin and Myosin

Sarcolemma

plasma membrane; fine transparent sheath enveloping skeletal muscles

Sarcomere

Contractile unit of muscle; repeated over and over along a myofibril

Skeletal muscle cells into muscle: Smallest to Largest

Muscle fiber/cell (contained by sarcolemma), Endomysium, Fascicle (multiple muscle fibers held together by perimysium), Muscle (multiple fascicles held together by epimysium)

Muscle

multiple fascicles held together by epimysium

Fascicle

multiple muscle fibers held together by perimysium

Perimysium

Sheath of connective tissue surrounding bundle of muscle fibers

Epimysium

Sheath of fibrous elastic tissue surrounding a muscle

Neuromuscular Junction

The axon terminal and sarcolemma are separated by a space called the synaptic cleft; Neurotransmitter acetylcholine is released into the synaptic cleft via exocytosis and it diffuses across the synaptic cleft via exocytosis and it diffuses across synaptic cleft and triggers muscle contraction

Sliding Filament Theory

muscles need ATP and calcium ions to contract; myosin "heads" walk along the actin filament, shortening the muscle; contraction can last for as long as there are adequate ATP and CA+ stores

Muscles attach at two points

Bone or connective tissue

Origin

Stationary; immovable (or less movable) bone during movement

Insertion

More movable bone; muscle contracts across diarthrotic fibers (fibers shorten); Insertion towards the origin; Type of movement depends on joint type/shape and placement of the muscle

Agonist

Prime Mover; produces a movement

Antagonist

Opposes or reverses a movement; can also be prime movers

Bicep muscle of the arm

Agonist of flexion at elbow; motion is antagonized by the triceps

Triceps

prime mover of extension at the elbow

Synergist

Aid action of agonist by assisting or stabilizing; stabilizing is necessary when a muscle crosses two or more joints (ex. making a fist)

Fixator

Specialized synergist; immobilizes origin so all tension is on insertion; muscle that holds scapula in place during arm motions

Rectus

parallel (usually w/ midline)

Transverse

right angle midline

Oblique

Angled

Biceps

2 origins

Tricep

3 origins

Quadricep

4 places of origin

Adductor

muscles located on inner thigh; bring legs toward center of your body; motion of bringing legs inward is "adduction"

Flexor

Muscle whose contraction bends a limb or other part of the body; muscle that decreases the angle between bones

Extensor

Muscle whose contraction extends or straightens a limb or other part of the body

Phalanges

bones found in fingers and toes; has no muscle

Brain

Largest and most complex part of nervous system; sensation, perception, movement, thinking

Frontal Lobe

Executive functioning, multitasking

Temporal Lobe

Auditory Processing

Parietal Lobe

Interprets pain/touch; identifies objects; understands spoken language

Occipital Lobe

Vision

Grey matter

Center of Spinal Cord; Superficial layer; a.k.a cerebral cortex; cell bodies of cerebral neurons; unmyelinated region

White Matter

Outer area of Spinal Cord; Myelinated Axons

Gyri (Gyrus)

Fold

Sulci (Sulcus)

Depression

Fissure

Deep sulcus

Brainstem

Connects brain and spinal chord; the area where the majority of cranial nerves attach
3 Parts: Midbrain, Pons, Medulla

Communication between CNS and PNS

Brain -> Brainstem -> Spinal Chord -> PNS

Midbrain

Vision, hearing

Pons

Regulation; where cerebellum connects

Medulla

Conscious thought and involuntary control (breathing, heard, blood, vessels, digestion); exits through foramen magnum

Cerebellum

located under occipital lobe; responsible for coordination, posture, balance, motor skills; associated w/ physical movement, and unconscious coordination and equilibrium

Arbor Vitae

branching white matter in the cerebellum

Diencephalon

Region of brain that contains Epithalamus, thalamus, and hypothalamus

Pineal Gland

Body's internal clock; in the Epithalamus; circadian rhythm; secretes melatonin

Thalamus

Relay station and processing center for incoming sensory information (not smell); outgoing motor information

Hypothalamus

Autonomic functions; hormone production; homeostasis

Cerebral Spinal Fluid (CSF)

surrounds CNS; brain and spinal cord; provides support, cushioning and protection; contains and transports nutrients, waste, and chemical messengers; flows through ventricles; flows into a subarachnoid space

Chloroid Plexus

network of blood vessels in each ventricle of the brain; derived from pia meter and produces CSF

Meninges

3 layers of connective tissue that protect brain and spinal chord; Dura mater, Arachnoid Mater, and Pia Mater

Dura Mater

most superficial layer of of tissue around brain and spinal chord; attached to inner surface of thee skull

Arachnoid Mater

second superficial layer of of tissue around brain and spinal chord; weblike connective tissue

Pia Mater

third superficial layer of of tissue around brain and spinal chord; delicate, highly vascular, attaches to surface of the brain

Meningitis

inflammation of meninges

Nervous System

Integrates and coordinates; monitors and processes internal and external environment; homeostasis

Central Nervous System

Brain and Spinal Cord; primarily interprets incoming sensory info and issues response/instructions

Peripheral Nervous System

Nervous system elements other than CNS; sensory, cranial nerves, spinal nerves

Neuroglia

supports and protects neurons; astrocyte, ependymal cell, oligodendrocyte, shwann cell

Astrocyte

glial cell; IN CNS; most abundant; gives support and nutrients to neuron; controls chemical environment through the mopping up of leaked K+; blood brain barrier

Ependymal

glial cell IN CNS; aids in circulation of CFS and production

Oligrodendrocytes

glial cell in CNS; produces myelin sheath in CNS

Myelination

increases transmission speed of nerve impulse

Schwann Cells

most long nerve fibers that are covered w/ fatty myelin; nerves in the PNS are heavily myelinated by Schwann cells; wrap tightly around the axon; not continuous (gaps exist between cells)

Neuron

tissues of nervous system; made up of cell body, axon, axon terminal, synaptic cleft, dendrite

(pseudo) Unipolar Neuron

one short process that divides; often conducts impulses toward CNS

Bipolar Neuron

2 processes; rare-sight, smell, hearing

Multipolar Neuron

multiple dendrites; 1 axon; brain, spinal chord, neurons that carry messages away from CNS; MOST COMMON

myelin

insulating layer or sheath that forms around nerves; makes up myelin sheath

Cell body

nucleus and cytoplasm

Dendrite

receptive region of a neuron

Axon

Impulse generating and conductive region

Axon Terminal

End of Axon; transmitting portion of neuron; transmits information via neurotransmitters

Synaptic Cleft

Junction between axon terminal and next cell; where neurotransmitters are released

Neuron Information Flow

Dendrite -> Cell Body -> Axon -> Axon Terminal -> Synapse; a neuron can synapse with another neuron, muscle, or gland

Action Potential

this is how nerves send signals

Sensory/Afferent Neuron

carry impulses from organs, skin, skeletal muscles, special senses to TOWARD CNS; endings have specialized receptors that are stimulated by specific changes in environment; typically unipolar

Motor/Efferent Neuron

carry Impulses AWAY FROM CNS to the organs, muscles, and glads; typically multipolar

Somatic

voluntary

autonomic

involuntary

Autonomic Nervous System

controls many INVOLUNTARY functions (ex. digestion, urination, heart rate)

Parasympathetic

"rest and digest"; digestive function increases; heart rate decreases; bronchi constrict; pupils constrict; promotes emptying of bladder; stimulates saliva

Sympathetic

"fight or flight"; digestive function slows; heart rate increases; bronchi relax; pupils dilate; inhibits emptying of bladder; inhibits saliva

EEG (Electroencephalogram)

Records electrical activity of the brain; brain waves are always present - even hen unconscious; can be used to locate specific areas of concern; diagnostic tool for seizures

Grey Matter

Central Canal

Continuous w/ the ventricles of the brain; located in spinal cord; has CSF

Dorsal Root/Root Ganglion

Contains sensory neurons

Ventral Root

Motor Neurons

Spinal Nerve

Fusion of dorsal and ventral roots; mixed nerve (contains both sensory and motor fibers)

Epidural Space

Space between the spinal dura mater and the periosteum of the vertebral column; pain medicine and anesthesia is injected into this space along the spine