Movement - Compendium 6

Table of Content

Muscle
Muscle tissue types
Skeletal muscles

Skeletal Muscles in detail.
Layers
Cellular anatomy
Myofilaments

Contraction of the Muscle
Neuromuscular junction
Synaptic knob

Action Potential Sequence
Release of ACh
Binding of ACh
Conduction of action potentials

Bone Types
Osseous tissue
Calcium phosphate
Osteocytes
Osteclasts
Osteoblasts

Bone Growth & Repair
Remodeling
Calcium
Fracture repair


Muscles
Types of muscle tissue:
Skeletal- Muscles attaching to bones directly or indirectly, and are used to produce voluntary skeletal movement.
Cardiac- Involuntary muscle and only found in the heart.
Smooth muscle- Involuntary muscle and found in walls of organs.

Skeletal Muscles in detail.
Muscle layers consist of endomysium covering fibers.
Perimysium is the sheathing of the muscle.
Epimysium covers or is outer layer of muscle.
At the end of the muscle is a tendon connecting to bones.
Muscle cells have a sarcolemma which form T tubules and touch the sarcoplasmic reticulum which store calcium ions.
Myofilaments make up the contracting parts of the muscle fiber.
The thin filament (actin) and a thick filament (myosin).

Contraction of the Muscle
Neuromuscular Junction are were the impulses link between electrical activity in the sarcolemma and the initiation of a contraction of the muscle units.
Synaptic knob, synaptic cleft, and motor end plate are part of this junction.
Action Potential Sequence
Impulses at synaptic knob release ACh into synaptic cleft. The ACh binds at the motor plate. The permeability of the membrane is changed to sodium ions.
This conduction of action potentials by the sacrolemma: This triggers a sudden release of calcium ions causing a contraction.

Bones Types
Osseous -Supports connective tissue contains specialized cells, extra cellular fibers, and ground substances.
Calcium Phosphate accounts for majority of bone weight
Osteocytes -Mature bone cells that recycle calcium and assists with bone repairs.
Osteoclasts- Giant cells; helps regulate calcium and phosphate concentrations in the body’s fluid.
Osteblasts- Cells responsible for the production of new bone.

Bone Growth & Repair
Organic and mineral components of bone are continuously recycled and renewed.
Calcium is the most abundant mineral in the body. 99% is located in the skeleton, which acts as a calcium reserve for the body.
Fracture repair involves the formation of a fracture hematoma, and then slow calcium build up and bone growth.
Aging factors of the skeleton can include osteopenia and osteoporosis.