Unit 2.2 Flashcards
Myoblast
Myocyte
Immature muscle cell
Mature muscle cell
Sacrolemma
Sacroplasm
Layer or sheet, used to indicate a muscle cell membrane
Cellular fluid, used to indicate the unique cellular fluid found in myoctyes
Classification of muscle tissue
Appearance, type, innervation (neural control)
Striated muscles _ protein
Nonstriated _ proteins
Have
Don’t have
Cardiac muscle is known as
Myocardium
Skeletal nervous system
Cardiac
Smooth
Somatic motor
Autonomic
Autonomic
Nuclei?
Skeletal
Cardiac
Smooth
Many per muscle cell
2-3 per muscle cell
1 per muscle cell
Voluntary muscles
Involuntary muscles
Skeletal
Smooth and cardiac
Functions of skeletal muscle
Produce skeletal movement
Maintains posture and body position
Supports and protects organs
Guards entrances and exits of the body
Maintains body temperature
Formation of skeletal muscle
Myoblasts coalesce in embryonic
Myoblasts fuse to one another to create a
Some myoblasts are retained in the surface of muscle fibers and will aid in
Mature muscle fibers are
Mesoderm
Linear long muscle
Repair of muscle
Multinucleated due to this development process
Muscle fibers coalesce to create
Muscle fibers within a muscle fascicle are connected to one another by
Muscle fascicle coalesce to create
Muscle fascicle within a muscle are connected to one another by
Fascicles
Endomysium
Individual muscles
Perimysuim
Individual muscles organize and migrate down the limb bud together to form
Individual muscles are surrounded by a
Muscles within muscle compartments have
Muscle compartments
Connective tissue termed epimysuim
Have related actions
Epimysuim
Perimysuim
Endomysuim
Around the entire muscle
Between muscle fascicle
Between individual muscle fibers
One muscle fiber consists of many
Runs the entire length of the cell and shorten the cell during contraction
Each muscle fiber is surrounded by a _ which navigates to form an internal membrane _
Myofibrils
Myofibers
Sarcolemma
Sarcoplasmic reticulum
SR’s communicate with transverse tubules and end as
Sarcoplasm is found between
Mitochondria and lysosomes are found in
Terminal cisterns
Individual myofibrils
Abundance within the sarcoplasm
Myofibrils are composed of
Myofilaments are composed of
They are _ than the individual muscle cell (Myofiber)
Thick filaments
Thin filaments
Many microfilaments
Thick and thin contractile proteins and other structural proteins
Longer
Myosin
Actin
Sarcomeres are also known as
When Ca2+ is released there is a cascade of biochemical events that cause
The net effect is the shortening of
Functional and contractile unit
The contractile proteins to bind and slide past each other
Muscle cell
The sacromere contains
Region is
Alternating dark and light striations within myofibrils due to the presence of contractile proteins
Between two z discs
Actin appears
Region of sarcomere
Myosin appears
Region
Light and is known and thin filament
I band- isotrophic (visually similar)
Dark and called thick filament
A band- anisotropic (complex)
An H zone is present in the center of the
The thin filaments do not overlap with thick filaments in this region when a muscle is
The h zone disappears when the thin filaments slide toward the middle of the sarcomere during
The sliding filament theory states that when thick and thin filaments slide past each other the sarcomere
A band
Relaxed
Muscle contraction
Shorten- contracts
A neuromuscular junction is created when the synaptic knob of a nerve cell innervates
A nerve impulse initiates the release of
Neurotransmitters are held in synaptic knob and released through
One neuron will innervate _ muscle fibers within a muscle
Skeletal muscle is often referred to as a
Muscle fiber
Neurotransmitter
Exocytosis
Multiple
Motor neuron unit
In skeletal muscle the neurotransmitter, _, is released by the synaptic knob into the synaptic cleft
Acetylcholine
The four properties of muscle tissues
Contractility- ability of muscle to shorten or contract
Extensibility- ability to be extended or stetched with in limits
Excitability- the susceptibility of muscle tissue to rest to external stimuli allowing it to react instantly when stimulated
Elasticity- te ability to return to its original state after being stretched
Muscle fascicle create _. The direction _ in addition to relative origin, insertion, and action. They are
Individual muscle
Dictates
Circular
Parallel
Uniennate, bi, multi
Which muscle fiber protestation exerts most force?
At one discrete point
Sheer number of muscle fibers per length
Convergent
Multipennate
Which muscle fascicle orientation allows for greatest range of motion
Convergent- differing fiber orientation increases range of motion
Which muscle fascicle form is most numerous in the human body
Unipennate- due to muscles in the appendages
Naming of muscles
Structure - fiber orientation
Function
Shape
Location
Number of heads
Attachment sites
Ligaments
Attach bone to bone and increase stability during action
Muscle tendons
Attach muscle to bone
Aponeurosis
Large sheets of connective tissue that acts as ligaments for larger muscles
Synovial sheaths
Synovial membranes that encase tendons
Bursae
Synovial fluid pouches found between muscle tendons and bines
Retinaculum found at _ to serve
Joints
Maintainment of positions of tendons
Muscles act on joints when
The points of attachment are in either side of the joint
Muscle always contracts toward
Origin- most stable point, proximal point
Muscles develop from _ and they organize into muscle tissue
Mesoderm
Primordial muscles migrate down developing limb bud and construct groups around the
Underlying skeletal structure
Fascia (dense) ct
Separates individual muscles from one another
Divides compartments from one another and creates passageways for neurovascular bundle
Synergists also act as
Fixators to stabalize a bone or joint while the prime mover performs the desired action
Antagonists must relax for
Prime mover to contract
Rectus abdominis and erector spine are
Antagonists
Agonist
Prime mover that elicits a particular action
