histology Flashcards
describe skeletal muscle (6)
straited, unbranched, multinulceated, nucleus pushed to membrane (sarcolemma), long cylinders, have satellite stem cells (mane new muscle)
what are muscle fibres grouped into
fascicles
what is the connective tissue that surrounds muscle as a whole called
epimysium
what is the connective tissue that surrounds single muscle fascicle as a whole called
perimysium
what is the connective tissue that surrounds muscle fibre as a whole called
endomysium
how is muscle organised
muscle –> fibres (cells) –> fascicles –> myofibril –> sarcomere
what are sarcomeres and where do they extend between
units of contraction, between Z lines which cause striations
what is a motor unit
a nerve and all the muscle fibres it innervates (alpha?)
where do axons of motor unit terminate
neuromuscular synapses
what are the 3 fibre types
type I (oxidative slow type), type IIa (intermediate), type IIb (anaerobic fast)
describe cartilages rigidness, permeability and vascular supply
semi-rigid, permeable, avascular
how are cartilage cells nourished
through ECM called lacuna that they secrete
what is the lacuna made of
75% water, 25% type II collagen and proteoglycan
what are the 3 types of cartilage
hyaline, elastic, fibrocartilage
what is hyaline cartilage
glassy, blue-white and transparent, common
what is elastic cartilage
light yellow, elastic and flexible
what is fibro cartilage
hybrid of tendon and hyaline, type 1 collage with chondrocytes, white
what is the outside, shaft/ diaphysis made up of in bone
dense cortical bone
what is the end of bones/ epiphysis made of
cancellous or trabecular bone
how does bone receive vascular supply
haversian’s channels (except trabecular bone)
what is bone grouped into
osteons
what are osteoprogenitors
stem cells that make osteoblasts
what are osteoblasts
bone forming cells
what do osteoblasts secrete
collagen, GAG’s, proteogylcans to make osteoid which is mineralised to bone
what are osteoclasts
break down bone
