| Question |
Answer |
| 3 connective tissue sheaths associated with muscle (from out to in) |
Epimysium, parimysium, endomysium |
| Dark bands are made up of? |
Thick fliaments, A-band, myosin filaments |
| Light bands are made up of? |
Thin filament, I-bands, F-actin chains |
| How fibers move during contraction |
Sliding motion over one another |
| Composition of M-line |
binding protiens, creatine kinase and myomesin |
| Which bands reduce in contraction |
H-bands and I-bands |
| What are the two types of muscle fibers |
Type I (Red) and Type II (white) |
| Characterisitcs of type I (red) muscle |
high myoglobin, highly vascular, lots of mitochondria, slow endurance, resistant to fatigue |
| Location of Type I muscle |
postural muscles of cervical and lumbar regions and higher levels of upper and lower limbs |
| Characteristics of Type II (white) muscle |
Low myoglobin, few mitochondria, low vascularity, easyily fatigued, fast movement, precise actions |
| Location of type II |
eye muscles, but mixes with type I |
| 3 components of a motor unit |
motor nueron, muscle fibers innervated by a single motor nueron and nueromuscluar junctions |
| What is a muscle spindle |
a sensory receptor |
| what does a muscle spindle sense/detect |
muscle tension and stretch |
| what are muscle spindles composed of |
intrafusal fibers |
| what type of tissue surround muslce spindles |
dense irregular |
| 3 types of muscle |
cardiac, skeletal, and smooth |
| Describe Cardiac muscle |
striated, single nucleus in the center of the cell, and branched. Involuntary and have intercalated disks |
| Describe skeletal muscle |
striated, longer than caridac, multiple nuclei on edge of cell |
| Describe Smooth muscle |
not striated, cigar shaped nuclei, single central nucleus |
| What is an intercalated disk |
found in cardiac cells, bind cells together so that they work as a unit |
| what tyoe of cell adhesions are found in an intercalated disk |
zonula adherens and desmosomes link the cell together, while gap junctions exist on lateral aspects |
| What are purkinge fibers |
cells that are 4-5 times the size of a normal cell, found in the interventricula space, and relay information very fast |
| What are Nodal fibers |
found in SA and AV nodes, set basic rhythum for the heart, smaller than normal cells |
| What are dense bodies |
found in smooth muscle, serve much like Z-disks to help anchor filaments using a-actinin |
| Which muscle tissue is mitotically active? Give an example |
smooth, menstral cycle |
| Can the regeneration of smooth muscle become pathological |
YES |
| what cells are important for the formation of skeletal muscle |
satellite cells |
| What is Rhabdomyoma |
benign tumor of skeletal muscle |
| What is Leiomyosarcoma |
malignant tumor of smooth muscle |
Beef Production
