the musculoskeletal system Flashcards
the cartillage prevents the end of the bones from rubbing directly onto each other, true or false
true
some functions of the muscular system
Body movement (Locomotion)* Maintenance of posture
Respiration– Diaphragm and intercostal contractions
Communication (Verbal and Facial)
Constriction of organs and vessels– Peristalsis of the GI tract–
Vasoconstriction of blood vessels and other structures (pupils)
Heart beat
Production of body heat (Thermogenesis)
properties of the muscle
Contractility: ability of a muscle to shorten and generate pulling force
Excitability: capacity of muscle to respond to a stimulus
Extensibility: muscle can be stretched back to its original length
Elasticity: ability of muscle to recoil to original resting length after
functions of skeletal muscles
Responsible for locomotion, facial expressions, posture, respiratory movements, other types of body movements…
skeletal cells are mononucleated, true or false
false, they are multinucleated
they are formed by the fusion of mononucleated myoblasts during their development
skeletal muscles are said to be controlled by which neurons
somatic motor neurons
therefore, they initiate voluntary muscle contractions
skeletal muscles are striated, true or false
The term “striated” in the context of skeletal muscles refers to the striped or banded appearance of muscle fibers when viewed under a microscope.
true
functions of the smooth muscle
propel urine
mix food in digestive tract
dilating/constricting pupils
regulating blood flow
the smooth muscles are controlled involuntarily by which body systems
the endocrine and autonomous nervous systems
smooth muscles are mononucleated, true or false
true
smooth muscles are striated, true or false
false
smooth muscles are autorhythmic in some locations in the body, true or false
true
are cardiac muscles striated ?
are they mononucleated?
yes
yes
which body systems control the cardiac muscle
Controlled involuntarily by endocrine and autonomic nervous system
both are points where the muscle attaches to the bone
difference between the insertion and the origins
This is the movable or distal attachment point of a muscle. It is typically the end of the muscle that is furthest from the body’s midline or core
while
This is the fixed or proximal attachment point of a muscle. It is typically the end of the muscle that is closest to the body’s midline or core.
name the two ways in which the muscles attach to the bones
indirect attachment
direct attachment
the most common form of attachment is the indirect one
during indirect attachment to the bone, what happens to the epimysium, and where does it attach to
Epimysium extends beyond muscle as a tendon
Attaches to periosteum of bone
during direct attachment to the bones, what happens to the epimysium
it fuses or adheres to the periosteum
name the three connective tissue layers that surround the skeletal muscle
Epimysium: The outermost layer of connective tissue that surrounds the entire muscle.
Perimysium: A layer of connective tissue that surrounds each bundle of muscle fibers called a fascicle.
Endomysium: The innermost layer of connective tissue that surrounds individual muscle fibers.
the cell membrane surrounding the muscle fibre is known as
sarcolemma
made of repeating units of sarcomere
the 2 main contractile proteins found in the muscle fibres
actin and myosin
These proteins are organized in a highly structured manner within the muscle fibers and interact during muscle contraction to generate force and produce movement
the basic functional unit of the muscoloskeletal system
joints
the three types of joints
Fibrous
Cartilaginous
Synovial
there are 4 answers to this
muscles fibres vary depending on?
The predominant pathway utilized to synthesize ATP - aerobic or anaerobic
The amount of myoglobin (oxygen store) – high or low
The type of work they do – sustained or short
Efficiency of ATPase - decompose ATP slowly or rapidly
fibrous joints contain connective tissue and can move, true or false
false, they cannot move but contain connective tissue
how many types of fibrous joints do we have
name them
3
Suture
Syndesmosis Gomphosis
they have no joint cavaties
cartilaginous joints entirely connected by?
cartillage
how many types of cartilaginous joints?
name them
2
Symphyses: Symphyses are permanent cartilaginous joints characterized by the presence of fibrocartilage between the articulating bones
Synchondroses: These are temporary cartilaginous joints where the connecting material is hyaline cartilage.
the most mobile joint type
the least mobile joint type
synovial
fibrous
note that the cartilaginous ones allow little movement
the weakest joint type
the most common joint type
synovial joints
synovial joint
the basic components of synovial joints
articular cartillage
joint capsule
synovial cavity(contains synovial fluid )
ligaments
tendons
synovial membrane
articular cartillage made up of hyaline cartillage. only called”articular cartillage” because it aids articulation of the synovial joints
function of the synovial fluid
lubricates the joint and nourishes the articular cartilage.
reduces friction between the bones and allows for smooth movement.
do the articular cartilages at each end of the knee joints ever come in direct contact?
give a reason for your answer
no they do not
because they are separated by a thin film of joint fluid and two “shock absorbers” made of a different type of cartilage
note that these shock absorbers are the menisci(plural for meniscus)
cartillages are said to be avascular, what does this mean
they do not have blood vessels
main components of cartillages
gelatinous ground substance containing molecules such as chondroitin sulfate
the ground substance of the cartillage is comprised of?
Collagen
Fibres of the protein elastin
note that the ground substance forms the extra-cellular matrix of the cartillage
functions of the cartilage
provides support, flexibility, and resistance to compression
the three types of cartillage
elastic cartilage
fibrocartilage
hyaline cartilage
function of ligaments
usually serve to hold structures together and keep them stable.
outline the organisation of the muscle in hierarchical order
muscle
fascicles
muscle fibres
myofibrils
myofilaments
properties of slow-twitch muscle fibres
Contract relatively slowly and generate less force.
Suited for endurance activities such as long-distance running or cycling.
Rich in mitochondria, allowing them to sustain energy production for longer periods.
Highly resistant to fatigue due to their efficient energy utilization.
Typically appear red in color due to their high myoglobin content, which aids in oxygen storage.
these fibres are fatigue-resistant
some properties properties of fast-twitch fibres
Contract rapidly and generate greater force.
Suited for activities requiring short bursts of power, such as sprinting or weightlifting.
Less rich in mitochondria compared to slow-twitch fibers, leading to quicker fatigue.
Can be further classified into Type IIa (fast oxidative) and Type IIb (fast glycolytic) fibers based on their energy metabolism and fatigue resistance.
Often appear white in color due to lower myoglobin content.
