Test 2 Flashcards
Bone (osseous connective tissue)
- hard matrix with mineral salts
- matrix arranged in lamellae around haversian canal
- osteocytes in lacunae
Compact Bone
- shafts of long bones, parallel plates of flat bones
- structural unit – Haversian system
- Haversian canals
- Volkmann’s canals
- matrix arranged in lamellae around Haversian canal
Spongy Bone
- ends of long bones, center of irregular bones
- no Haversian system
Intramembranous Ossification
- bones of the skull, clavicule
- concentration of mesenchyme
- cells producing collagenous fibers and osteoid
- later deposition of salts
Enchondral Ossification
- cartilage model
- formation of primary ossification center
- blood vessels enter the ossification center
- formation of secondary ossification center
- formation of bone marrow cavity
Smooth Muscle
- unstriated
- involuntary (innervated by autonomic nervous system)
- in the walls of visceral organs
- small elongated cells which posess centrally located nucleus
Cardiac Muscle
- striated
- involuntary
- in the heart
- single nucleus, cells connected with special junctions – conducting electrical impulses
Skeletal Muscle
- striated
- voluntary (innervated by somatic nerves)
- attached to the skeleton
- multinucleated
Structure of a Skeletal Muscle

Structure of a Skeletal Muscle Fiber

Sarcomere Structure

Structure of a Thin Filament

Structure of a thick filament

How changes in striation pattern are explained by the sliding-filament model of muscle contraction:

Events in Excitation-Contraction Coupling

Actions of troponin and tropomyosin in excitation-contraction coupling

Skeletal muscle contraction
- basic structure involved in contraction consists of myofilaments
- thick filaments – myosin
- thin filaments – actin and tropomyosin
- filaments slide along each other during contraction / relaxation
- sarcomere – functional unit of the striated muscles
- ATP = ADP+Pi
- ATP from
- aerobic glycolysis
- anaerobic glycolysis
The Crossbridge Cycle

Types of Muscle Contraction
differ in whether the muscle is allowed to shorten as it contracts or not
Isotonic Muscle Contraction
- When a muscle contracts isotonically it generates a tension at least equal to to any forces oposing it (called loads) and so the muscle shortens.
- constant tension
Isometric Muscle Contraction
- When a muscle contracts isometrically it creates tension but does not shorten because the load is greater than the force generated by the muscle.This occurs for example when you try to lift an object that’s too heavy for you to move, or when you stand still and your postural muscles hold your body upright.
- constant length
Neuron (Nervous tissue)
- nerve cell
- is the basic structure of the nervous tissue
- each neuron consists of:
- cell body
- processes
- long (axons)
- short (dendrites)
Structure of a Nerve

Structure of a Typical neuron










