Bone structure and core MSK histology Flashcards
Describe the histological appearance of skeletal muscle
- Striated
- Unbranched
- Multinucleated (nuclei located preipherally)
Appreciate that Muscle fibres are grouped into bundles called fascicles and a muscle typically contains several fascicles.
- What is the connective tissue that surrounds the muscle as a whole called ?
- What is the connective tissue which surrounds a fascicle called?
- What is the connective tissue called which surrounds a single muscle fibre called ?
- Epimysium surrounds muscle as a whole
- Perimysium surrounds a single fascicle
- Endomysium surrounds a single muscle fibre
Why do skeletal muscles look striated ?
Because the Z-lines in the sarcomere of one myofibril will be aligned with the Z-lines of the sarcomeres in the surrounding myofibril.
The axon of the motor neurone branches as it nears its termination and each branch ends in a special type of synapse called…?
The neuromuscular junction
What type of muscle is shown in the micro pic ?
Skeletal muscle - note the multiple nuclei and striations
What/where are the cells of the ECM in cartilage ?
Chondrocytes - live in a space within the ECM termed a lacuna
What is the ECM of cartilage made up of ?
- 75% water
- 25% organic material - 60% of which is Type II collagen and 40% is proteoglycan aggregates
Hyaline cartilage is the most common type (also there is fibrocarilage and elastic) where is hyaline cartilage found ?
- Articular surfaces
- Tracheal rings
- Costal cartilage
- Epiphyseal growth plates
- Precursor in fetus to many bones
What are the functions of bone ?
- Support
- Movement
- Protection
- Calcium store
- Haemopoiesis
What is the composition of bone ?
- 65% mineral (calcium hydroxyapatite crystals)
- 23% collagen
- 10% water
- 2% non-collagen proteins
What are the two main types of bone and describe there appearance/where they are in terms of the bone as a whole
Cortical bone - dense outer shell makes up the shaft (diaphysis)
Cancellous or trabecular bone - occupies the ends of bone (epiphysis). It is a fine meshwork that looks like the inside of an aero bar.
Appreciate that in both compact and trabecular bone the only main difference is the presence of spaces the rest is similar
appreciate this
Label the structures in the pic and what type of bone is shown?
Cortical bone
What are cement lines ?
They are lines which often surround osteons, they are formed during remodelling