Exam 3 Flashcards
endomysium
Thin fascial sheath that surrounds the cell membrane of each muscle fiber.
perimysium
Bundles of muscle fibers are called fasciculi, which are surrounded by perimysium
epimysium
Entire muscle covered by
What innervates:
Skeletal muscle?
Smooth muscle?
Cardiac muscle?
Skeletal muscle: somatic nervous system
Smooth muscle: Autonomic Nervous System
Cardiac muscle: Involuntarily controlled– contractions are regulated by intrinsic fibers, hormones, and ANS
Where do you find:
Skeletal muscle?
Smooth muscle?
Cardiac muscle?
Skeletal muscle: Comprises 40-50% of total body weight and is made up of over 600 individual muscles
Smooth muscle:wall of hollow visceral organs and tubes, blood and lymphatic vessels, iris, etc
Cardiac muscle: walls and partitions of the heart
Striated or non-striated:
Skeletal muscle?
Smooth muscle?
Cardiac muscle?
Skeletal muscle: Striated
The Smooth muscle: Non-striated
Cardiac muscle: Striated
Size
Smooth muscle?
Cardiac muscle?
Smooth muscle: Relaxed smooth muscle are 30-200 um, thickest in the middle (3-8 um) and tapered
Cardiac muscle: 50-100 um in length and 14 um in diameter
Which muscle remains contracted and how much longer?
Cardiac muscle: Single action potential remains contracted 10 to 15 times longer than skeletal muscle
Fast fibers:
- anaerobic metabolism
- large in diameter
- densely packed mofibrils
- large glycogen reserves
- few mitochondria
- aka: white muscle fibers, fast-twitch glycolytic fibers, and Type II-A fibers.
Slow fibers:
- half the diameter of fast fibers
- take three times as long to contract after stimulation
- dramatically higher oxygen supply
- contain the red pigment myoglobin
- dark red
- aka: red muscle fibers, slow-twitch oxidative fibers, and Type I fibers
Nucleus:
Skeletal muscle?
Smooth muscle?
Cardiac muscle?
Skeletal muscle: Multinucleated
Smooth muscle: single nucleus
Cardiac muscle: single nucleus (possibly 2)
Muscle examples of 1st class levers
Unusual in the musculoskeletal system
Triceps in elbow
Raises head off chest. Posterior neck muscles provide the effort. Atlanto-occipital joint is the fulcrum, the weight lifted is the facial skeleton.
Muscle examples of 2nd class levers
Unusual in the musculoskeletal system
A push-up
Extension of the metatarsal phalangeal joint while standing
Stand on tip-toe
Muscle examples of 3rd class levers
Most of the musculoskeletal levers in the body are 3rd class
Psoas Major origin
T12-L5
Psoas Major insertion
Lesser trochanter of femur
Psoas Major nerve
L2-L4
Psoas Minor origin
T12 and L1
Psoas Minor insertion
Pectineal line and iliopectineal eminence
Psoas Minor nerve
L1 2
Iliacus origin
Superior 2/3 of iliac fossa, iliac crest and ala of sacrum
Iliacus insertion
Lesser trochanter of femur
Iliacus nerve
Femoral (L2-L4)
Pectineus origin
Pectineal line of pubis
Pectineus insertion
Pectineal line femur
Pectineus nerve
Femoral n.
Tensor Fasciae Latae origin
Lanteriorsuperior iliac crest
Tensor Fasciae Latae insertion
iliotibial tract
Tensor Fasciae Latae nerve
Superior gluteal (L4 5 S1)
Sartorius origin
(ASIS) Anterior superior iliac spine
Sartorius insertion
Pes anserine
Sartorius nerve
Femoral (L2 3 (4))
Vastus medialis origin
medial lip of linea aspera
Vastus medialis nerve
femoral
Vastus medialis insertion
tibial tuberosity via quadriceps tendon
Vastus intermedius origin
prox. 2/3 anteriolateral surface of femur
Vastus intermedius nerve
femoral
Vastus intermedius insertion
tibial tuberosity via quadriceps tendon
Gluteus Maximus origin
ilium
sacrum
thoracolumbar fascia
sacrotuberous ligament
Gluteus Maximus insertion
Gluteal tuberosity and iliotibial tract
Gluteus Maximus nerve
Inferior gluteal (L5 S1 2)
Gluteus Minimus origin
ilium
Gluteus Minimus insertion
greater trochanter
Gluteus Minimus nerve
Superior gluteal (L4 5 S1)
Gluteus Medius origin
ilium
Gluteus Medius insertion
greater trochanter
Gluteus Medius nerve
Superior gluteal (L4 5 S1)
Piriformis origin
sacrum
Piriformis insertion
greater trochanter
Piriformis nerve
S1-2
Gemellus Superior origin
ischial spine
Gemellus Superior insertion
greater trochanter
Gemellus Superior nerve
L5 S1
Obturator Internus origin
obturator membrane
Obturator Internus insertion
greater trochanter
Obturator Internus nerve
L5 S1
Gemellus Inferior origin
ischial tuberosity
Gemellus Inferior insertion
greater trochanter
Gemellus Inferior nerve
L5 S1
Quadratus Femoris origin
ischial tuberosity
Quadratus Femoris insertion
intertrochanteric crest
Quadratus Femoris nerve
L5 S1
Vastus Lateralis Origin
Greater trochanter
Intertrochanteric line
Linea aspera
Vastus Lateralis Insertion
Tibial tuberosity
Vastus Lateralis nerve
femoral
Rectus femoris origin
AIIS and superior brim of acetabulum
Rectus femoris insertion
tibial tuberosity
Rectus femoris nerve
femoral n
Semimembranosus Origin
Ischial tuberosity
Semimembranosus Insertion
Medial condyle of tibia
Semimembranosus nerve
sciatic nerve
Semitendinosus Origin
Ischial tuberosity
Semitendinosus Insertion
Pes anserinus
Semitendinosus nerve
Sciatic
Biceps Femoris (long and short heads) Origin
Long: Ischial tuberosity, sacrotuberous lig.
Short: Linea aspera
Biceps Femoris (long and short heads) Insertion
Long: head of fibula
Short: head of fibula
Biceps Femoris (long and short heads) nerve
long head: tibial
short head: common fibular nerve
Gracilis origin
Lateral inferior ramus of pubis and ischium
Gracilis insertion
pes anserine
Gracilis action
Knee flexion and internal rotation, hip adduction
Gracilis nerve
Obturator
Adductor Brevis origin
inferior ramus of pubis
Adductor Brevis insertion
Upper 1/3 of linea aspera
Adductor Brevis action
Hip adduction, slight medial rotation, extension, flexion
Adductor Brevis nerve
Obturator
Adductor Longus origin
Body of pubis
Adductor Longus insertion
medial lip of linea aspera
Adductor Longus action
Hip adduction, slight internal rotation, extension, flexion
Adductor Longus nerve
Obturator
Adductor Magnus origin
ischial tuberosity and inferior ramus of ischium and pubis
Adductor Magnus insertion
Entire length of linea aspera; medial supracondylar ridge of femur, and adductor tubercle
Adductor Magnus action
Hip adduction, external rotation, extension (lower portion), flexion (upper portion)
Adductor Magnus nerve
Obturator and Sciatic
Popliteus origin
posteromedial part of tibia