Muscle Tissue

Upcoming events:

• muscle tissue today

• muscle tissue NOT on Exam #1

• Exam #1 this Thursday• Bring a scantron form & a pencil• BE ON TIME!

1. Name this structure

2. Name this structure (be specific)

3. Give one function of the structure in #2 (be specific)

4. List at least 6 movements that theshoulder can make

5. List at least 4 movements that theTMJ can make

Muscle Tissue

• 3 types of muscle tissue• basic histology• What is a muscle fiber?• Connective tissue wrappings• types of muscle attachments• neuromuscular junction• smooth and cardiac muscle

skeletal cardiac smooth

Muscle fiber = muscle cell

• Skeletal muscle fibers are multinucleated• Muscle fibers are wrapped with connective tissue

Myoblasts fuse

Skeletal muscle fibers:• multinucleated• striated• excitable• contract• extensible• elastic• wrapped with CT• hypertrophy• atrophy

TendonDeep fascia

EpimysiumEpi = upon, above

PerimysiumPeri = around

EndomysiumEndo = within

Connective tissue wrappings of skeletal muscle

Myo, mys = muscle

Bellies

Insertion

Insertion

Origins Origins

Muscle attachments

Ligaments: bone to boneTendons: muscle to bone

Direct vs Indirect attachment

Aponeurosis

Muscle to skinMuscle to muscle via tendon

Neuromuscular junction

Fig. 10.12(TE Art)

Synaptic vesicles(containing ACh)

Motor endplate

ACh = acetylcholine

Fig. 10.15p270a(TE Art)

Neuron release AChElectrical excitationspreads across musclefiber and down T tubules

Ca2+

Release Calcium Calcium + ATP = muscle contraction

Neurotoxins...

Rigor Mortis

• What is rigor mortis?

• Why do the muscles contract after death?

• Why do they remain contracted for up to 24 hours?

• Why does rigor mortis only last 24 hours?

Fig. 10.17b

Fig. 10.19(TE Art)

Muscularis externa

Mucosa

Circular layer

Longitudinal layer

Submucosa

Epithelium

Lamina propriaMuscularis mucosae