Histology of the musculoskeletal system Flashcards
What makes up the extracellular matrix in connective tissue?
Glycoproteins/ Glycosaminoglycans and interstitial fluid
What are three different types of connective tissue?
Collagenous fibres, Reticular fibres and Elastic fibres
What are some functions of skeletal muscle?
Movement, support, protection and thermoregulation
What kind of contraction is skeletal muscle?
Voluntary contraction
What is skeletal muscle sub-divided into?
Fascicles that are surrounded by perimysium and myofibres surrounded by endomysium
What is a myofibre?
Cellular unit of skeletal muscle
What is the sarcolemma?
The cell membrane of skeletal muscle
What is the sarcoplasm?
The cytoplasm of skeletal muscle
What is a slow-twitch skeletal muscle fibre?
contains lots of capillaries, mitochondria and myoglobin, low force of contraction but can contract for long periods of time, usually used for aerobic respiration
What is a 2A fast twitch muscle fibre?
Fatigue resistant, has an intermediate number of mitochondria and glycogen content
What is a 2B fast twitch muscle fibre?
Fatigue sensitive, with a low mitochondrial and glycogen content- used for anaerobic respiration
What is the function of titin?
stabilises the myosin
What is the function of the nebulin?
associates with the actin
What is the function of the Dystrophin?
Connects the cytoskeleton to the extracellular matrix
What kind of contraction is smooth muscle and what are some of its functions?
Peristalsis, regulation of blood flow, urination and respiration
What kind of shapes are the myocytes in smooth muscle?
Spindle shaped
What does unitarian mean?
contains gap junctions
What does multiunit mean?
contains no gap junctions
What is the main difference between smooth muscle and dense connective tissue?
Dense connective tissue is a lot thinner, they are more cigar shaped in smooth muscle
What are the two layers of periosteum that line the bone?
The outer is the fibrous layer and the inner is the osteogenic layer which is more cellular
What are the two different types of matrix in bone cells?
Woven (immature) and lamellar (mature)
What are the two different types of lamellar matrix?
Compact (dense deposits of matrix with a few spaces in-between) and spongy (cancellous trabecular)
What is compact bone?
Very strong, flexion-resistant bone found along the outer surface- its structural unit is the osteon which converts mechanical force into biomechanical stimuli
What are lacunae?
spaces between lamellae occupied by osteocytes
What is trabecular bone?
Made up of metaphysis and epiphysis- transmits forces from joint surfaces to compact bone
What lines trabecular bone?
lined by endosteum (similar to periosteum)
What is a difference between trabecular and compact bone?
Compact bone has central canals and trabecular bone does not and trabecular bone is surrounded by marrow
What is woven bone?
Weak, haphazard collagen arrangement, contains many osteocytes
What is lamellar bone?
Has a regular arrangement of collagen fibres, a lot stronger than woven bone
What is perichondrium?
Lines cartilage
In what areas can chondrocytes divide?
In cartilage but not in bone
What are isogenic groups?
clusters of 2-3 daughter cells in lacunae
Where are type II collagen fibres usually found?
widely dispersed throughout hyaline cartilage
