Lesson 1 Flashcards
what are the 3 types of muscle
skeletal
smooth
cardiac
T or F: smooth muscle is striated
F: skeletal and cardiac muscle are due to the organization of the sarcomeres
T or F: skeletal muscle only has one nucleus per cell
F: multinucleated. Cardiac has one or two nuclei, smooth has one nuclei per cell
What are some unique structural characteristics of cardiac muscle
intercalated disk
desmosomes
gap junctions
What type of muscle can we voluntary control? What is the exception to that?
skeletal
diaphragm
desmosomes connect what to what? hemidesmosomes?
desmosomes: cell to cell
hemid: cell to basement membrane
what do gap junctions allow for in cardiac muscle cells?
rapid communication of the electrical impulse between cells
smooth muscle has ________ control, contractions produce ________, and they are organized in__________
involuntary
constriction
multidirectional contractile units
_________ surrounds muscle, __________- surrounds fasicles, _________- surrounds a fiber
epimysium
perimysium
endomysium
Give examples of muscles for the following muscle types
fusiform
parallel
convergent
unipennate
bipennate
multipennate
circular
biceps brachii
rectus abdominis
pec major
palmar interossei
rectus femoris
deltoid
orbicularis occuli
What are some other types of cells found in skeletal muscle?
- mature myofibers
- adipocytes
- fibroblasts
- circulatory system cells
- satellite cells
- nervous system cells
What are the 2 types of mature myofibers?
extrafusal: normal contractile
intrafusal: maintain tension of muscle spindles
what are the 3 types of adipocytes
white, beige, brown
what are the jobs of fibroblasts
- make/organize connective tissue
- maintain signaling niches
- wound healing
- progenitor cells
which cells in the muscle tissue support neurons and promote regenerative growth
satellite glial cells (not muscle satellite cells)
which cells line axons in PNS
schwann cells
Which cell covers the schwann cell at the NMJ and cement axon to the muscle
kranocyte
_________ respond to changes in length and are located in the muscle fibers, _________ respond to changes in force and are located at the myotendon junction
muscle spindles
golgi tendon organ
what are 2 joint kinesthetic receptors
ruffini and pacinian corpuscles
_____________ found in joint capsule and respond to pressure, __________ found in connective tissue around the joint and respond to accel/decell of joints
ruffini corpuscles
pacinian corpuscles
T or F: fiber type % and cross sectional area of muscles are the same between sexes
F: cross sectional area is different but not fiber type %
what is the purpose of a T-tubule
allow AP to penetrate nearer to the internal structures of the fiber
what makes up a triad
T-tubule + 2 flanking terminal cisternae
what is the contractile unit
myofibril
T or F: a sarcomere is M line to M line
F: Z disc to Z disc
T or F: actin is stationary and pulls myosin during a muscle contraction
F: actin is what moves during a contraction, myosin pulls actin
What do we need to know about myosin heavy chain purpose? myosin light chain?
heavy - they don’t all contract at the same speed
light - controls how close the myosin head is to actin
Myosin is an ________
ENZYME
Titin’s purpose?
acts as a spring and holds actin to the z disc
*largest know protein
*provides passive tension
Nebulin’s purpose?
is in the center of actin and keeps it organized
*large protein (not bigger than titin)
*“molecular ruler”
what are the different populations of mitochrondria?
1 - subsarcolemmal (cluster at nucleus and neuromuscular junction)
2 - intermyofibrillar
What type of tissue has the most mitochondria?
cardiac
list the types of skeletal muscle from most mitochondria to least
type 1>2a>2x>2b
T or F: smooth muscle has more mitochondria than skeletal
F: smooth is really variable so it depends
_______ connects the sarcolemma to the basil lamina
Laminin
