LECT 3: muscle physiology

Name voluntary muscle(s)

skeletal

name involuntary muscle(s)

smooth and cardiac

what kind of contraction occur in skeletal muscles?

rapid contraction

what kind of contraction occur in smooth muscles?

slow contraction

what kind of contraction occur in cardiac muscles?

contract as a unit

Which muscle(s) striated?

skeletal and cardiac

which muscle(s) nonstriated?

smooth

what kind of fibres do skeletal muscles have?

long straight bundles of fibres (cells)

what kind of fibres do smooth muscles have?

network of short fibres

what kind of fibres do cardiac muscles have?

branching fibres

which muscle(s) self-excitatory?

cardiac

\____ : involuntary, striated, branching fibres, self-excitatory, contract as a unit

cardiac

\____ : involuntary, nonstriated, network of short fibres, slow contraction.

smooth

\____ : voluntary, striated, long straight bundles of fibres (cells), rapid contraction.

skeletal

which muscle(s) depends on the innervation of spinal and cranial nerves?

voluntary

what do voluntary muscles depend on?

the innervation of spinal and cranial nerve

what are examples of the innervation of spinal and cranial nerves?

T4, CN, VII

which muscle(s) depends on the innervation Sympathetic and Parasympathetic nerves (ANS)?

involuntary

what do involuntary muscles depend on?

the innervation Sympathetic and Parasympathetic nerves (ANS)

which muscle(s) can beat on its own and is only regulated by the ANS for rate and force?

cardiac

___ - protein that regulates muscle contraction by altering the position of tropomyosin

Troponin

what are ligaments associated with?

joints

what are joints associated with?

ligaments

name two quadriceps muscles

Vastus Medialis and Vastus Lateralis

Name two of the hamstring muscles

Biceps Femoris and Semitendinosus

what's a muscle fibre?

an extension of a single cell

\______ : fascia, tendons, aponeuroses, orgin of muscle, and insertion of muscle

connective tissue of muscle

\______ - Sheet of dense connective tissue that encloses a muscle

fascia

What are tendons?

Connects muscle to bone

\_______ - Cordlike or bandlike mass of dense connective tissue that connects a muscle to a bone.

tendon

\_____ - Sheet of connective tissue that attaches muscles to bone, skin, and other muscles

aponeurosis

what do you call a flat and solid sheet of tendon which hooks muscles to bone, skin, and others?

aponeurosis

where is the orgin of muscle?

end on fixed side of joint

\_____: end on fixed side of joint

orgin of muscle

\____: End on moving side that changes the angle of the joint

insertion of muscle

what is the insertion of muscle?

End on moving side that changes the angle of the joint

what are muscle cells called?

fibres

Describe skeletal muscle

long and thin, hair-like

\______ are bundles of fascicles

muscles

what are muscles basically?

bundles of fascicles

\____ - bundles of muscle fibres in muscle that work together

fascicles

What are fascicles?

small bundle of muscle fibers

what does a muscle fibre consist of?

Sarcolemma, Sarcoplasmic Reticulum, Cisternae, and transverse tubules

\_____ - swollen ends of SR that concentrate Ca++...collects Calcium fluid

cisternae

\____ - extend sarcolemma into fibre between Cisternae

transverse tubules

\____ - Enlarged portion of the sarcoplasmic reticulum near the actin and myosin filaments of a muscle fiber.

cisterna

\____ - Cell membrane of a muscle fiber

sarcolemma

define -sarc

muscle tissue

myo means

muscle

\____ - anything going through it horizontally will go down into the transverse tubules and into muscle fibers itself

transverse tubules

\____—network of membranous channels within a muscle fiber.

sarcoplasmic reticulum

what does the sarcomere consist of?

z lines, sarcomere, myosin, and actin

thin actin filaments held by direct attachments to structures called \__________

Z lines

where do z lines appear?

the center of the I bands

\____ - functional units of fibre, Z line to Z line

sarcomere

\_____ - Structural and functional unit of a myofibril.

sarcomere

____ - Protein that, with actin, forms the filaments that interact to contract muscle fibers (Thic filaments)

myosin

\____ - thin myofilaments connected to Z lines

actin

\___ - Protein in a muscle fiber that forms the thin filaments that slide between filaments of the protein myosin, shortening the muscle fibers.

actin

what do myofilaments consist of?

Myosin Crossbridges or Heads, Tropomyosin, troponin,

\____ - globular proteins on actin filament covering Ca binding site

troponin

\____ - long strand of protein on actin filament

tropomyosin

what binds to actin and forms cross-bridges?

myosin heads

\____ - The synapse where a motor neuron axon and a skeletal muscle fiber meet

neuromuscular junction

simply define synaptic vesicles

tiny vesicles that store neurotransmitter

what is stored in the synaptic vesicles?

ACh

what is the synaptic cleft?

space between nerve and muscle

A small gap called the \______ separates the membrane of the neuron and the membrane of the muscle fiber

synaptic cleft

\______ - nuclei and mitochondria are abundant and the sarcolemma is extensively folded

motor end plate

\____ - folded region around synaptic bulb

motor end plate

\____ - swollen ends of nerve embedded in, but not touching, the sarcolemma

synaptic bulbs

\______ - are NOT shown on the Motor End Plate

neurotransmitter receptors

\___: Neurotransmitter receptors are not shown on the Motor End Plate. This is where Ach attaches and causes the muscle to contract. Cholinesterase (Achase) is then secreted to remove the Ach from neuroreceptors so the muscle can relax and contract again.

info

\______ \= insulin receptors, glycogen, myoglobin, creatine PO4

Unusual Metabolic Properties of Muscle to Ensure Sufficient Energy Production

what does muscle need?

insulin receptors, glycogen, myoglobin, creatine PO4

\_____ - Vast majority of here in the body to ensure ample supply of glucose \= ATP

insulin receptors

Where is glycogen stored?

sarcoplasm - liver and muscles

\____ - Stored in sarcoplasm for quick breakdown when blood sugar is low \= glucose \= ATP.

glycogen

\____ - Red pigment in sarcoplasm giving muscle its colour

myoglobin

\_________ - supplies continuous O2 even when blood supply is deficient, i.e. when physical activity has outstripped one's aerobic capacity to make ATP.

Haemoglobin-like molecule

\_____ - Contributes its high energy bond energy to re-form ATP when aerobic respiration becomes unable to keep up with demand for ATP production.

creatine PO4

what's an example of oxygen debt?

continued heavy breathing

what kind of respiration is needed for Oxygen debt?

aerobic

During oxgyen debt, ime is needed for \_____________ to resupply depleted ATP stores.

aerobic respiration

\_____ - O2 is depleted during prolonged muscle activity and must be replaced when activity ceases

oxygen debt

\____ - decreased ability of muscle to contract

fatigue

give me examples of energy sources which make ATP

Glycogen, Creatine PO4, and O2

Uncontrolled shivering when cold or feverish \= \_______

body warms up.

How does the body warm up?

muscle contractions like uncontrolled shivering when cold or feverish

\______ - Exercise liberates which Stimulates all tissues and organs to improve physiology due to increased demand.

myokines

what kind of systems are involved in Myokines?

neurogenesis, immune, and ALL

\____ - quick to contract and quick to fatigue

fast twitch

\____ - slow to contract and slow to fatigue

slow twitch

which muscle twitch includes most muscles?

intermediate

example of fast twitch muscles

hand and eye muscles

example of slow twitch muscles

postural muscles

example of intermediate muscles

most muscles

which muscle twitch is: richer in mitochondria and myoglobin, more ATP, and endurance?

slow twitch

which muscle twitch is lesser in mitochondria and myoglobin, less ATP, and run out of energy quickly

fast twitch

\____ - Muscles can be trained to some extent for slow and fast twitch functions.

intermediate