Chapter 7 Flashcards
what are the three major components of the musculoskeletal system?
bones, skeletal muscle, connective tissue
what are the two parts that make up the skeletal system?
axial and appendicular
(T/F) ? the axial skeleton consists of the upper and lower extremities.
false. the axial skeleton consists of the head, neck, and trunk.
what are the two most important functions of the skeletal system?
leverage and support
what is a lever arm?
a lever arm is the distance from the axis or fulcrum to the point at which a force is applied to the lever.
what is a fulcrum?
the pivot point of a lever
what are the three types of lever systems?
first class, second class, third class
what is the most rigid connective tissue found in the human body?
bone
what is trabeculae?
plates of calcified tissue that make up the innermost layer of bone.
what is the strong fibrous membrane that offer strength and stiffness to the skeleton?
periosteum
what are some examples of long bones?
humerus, radius, ulna, femur, fibula, tibia, metatarsals, metacarpals, phalanges
what are some examples of flat bones?
ribs, ilium, sternum, scapula
what are irregular bones?
the bones found in the skull, pelvis, vertebrae and consist of spongy bone with then compact bone on the exterior.
what is wolf’s law?
every change in the form and function of a bone or of their function alone is followed by certain definitive changes in their internal architecture and equally definite secondary alteration in their external conformation, in accordance with mathematical laws.
(T/F) ? one of the benefits of exercise is that it helps increase bone mass.
true
(T/F) ? the two categories of joints are synarthroses (non-synovial joints) and diarthroses (synovial joints).
true
the cartilaginous joints are made of what cartilage?
fibrocartilage or hyaline growth cartilage.
(T/F) ? in diarthrodial (synovial ) joints, the ends of the bones of the ones are free to move in relation to one another.
true
all synovial joints have what five characteristics?
joint capsule, a joint cavity enclosed by the joint capsule, a synovial membrane that Ines the inner surface of the capsule, synovial fluid that forms a film over the joint surfaces, hyaline cartilage that covers the joint surfaces.
what are proximal joints? example?
shoulder / hip are the most proximal and the foundation for the extremities. these joints generally have the greatest freedom of movement and have great deal od muscular support in fan-shaped arrangements.
what are the distal joints? example?
complex in structure (wrist, ankle) with variety of motions available with intricate control.
what does agonist mean? example?
a a muscle that is most effective in causing a certain joint movement. biceps brachia in a bicep curl.
what opposes the agonist?
antagonist
what is synergist? example?
a synergist is when two muscles have a common joint action but also have a joint action that opposes each other. there synergy occurs during the common joint action. (example) pectorals major and latissimus doors during internal rotation of the humerus.
(T/F) ? A stabilizer is a muscle or set of muscles that steady or support a joint so another muscle or sets of muscles may move a portion of the body.
true
which muscle dorsiflexes the foot?
tibialis anterior
what is the action of the rectus abdominis?
compresses the abdomino-pelvic cavity; and flexes the vertebral column.
what is the action of the transverses abdominis?
compresses the abdomino-pelvic cavity.
what is the origin of the serrated anterior?
outer surface of the first nine ribs.
what is the insertion of the pectorals major?
greater tubercle of the humerus
what nerve innervates the deltoid?
axillary nerve
what is the insertion of the biceps brachii?
tuberosity of the radius
what is the origin of the brachioradialis?
lateral supracondylar ridge of the humerus.
what is the insertion of the psoas major? actions?
lesser trochanter of the femur. flex the high; flex the trunk on the femur.
what makes up the posterior oblique system?
the posterior oblique system consists of the latissimus doors, gluteus maximus and the intervening thoraco-lumbar fascia.
what makes up the anterior oblique system?
the anterior oblique system consists of the obliques and the contralateral adductor muscles and the intervening abdominal fascia.
what makes up the deep longitudinal system?
the deep longitudinal system includes the erector spinal, the deep lamina of the thoraco-lumbar fascia, the sacrotuberus ligament and the biceps femoris muscle.
what muscles make up the inner unit?
the inner unit consists pf the multifidus, transverses abdominis, diaphragm and the pelvic floor.
what role does a muscle fiber’s arrangement play?
hinge - elbow and knee, this movement is limited to extension and flexion.
what is a hinge joint?
ball and socket - shoulder and hip, this movement provides the widest range of motion in all planes.
what is a ball and socket joint?
slow twitch and fast twitch. slow twitch - type I, red fiber, oxidative fibers, fatigue resistant. fast twitch - type II, white fibers, divided into type 2a and 2b, type 2a have moderate glycolytic and high oxidative capacities, type 2b have high glycolytic and low oxidative capacities.
