A&P1 Test 2 Flashcards
Name the four classifications of bones
long bones
short bones
flat bones
irregular bones
What are the ends of a long bone called?
Epiphysis
What is the shaft of a long bone called?
Diaphysis
Name the canal in the middle of a long bone
medullary cavity
Small channels connecting lacunae, allowing communication and nutrient exchange between osteocytes
Canaliculi
A canal in the center of an osteon that contains blood vessels and nerves
Central (Haversian) Canal
Small spaces within bone matrix that house osteocytes
Lacunae
Concentric layers of bone matrix in an osteon.
Lamellae
Bone-forming cells responsible for producing new bone matrix
Osteoblast
Bone-resorbing cells that break down bone matrix
Osteoclast
Mature bone cells that maintain bone tissue
Osteocyte
The structural unit of compact bone, consisting of concentric lamellae around a central canal.
Osteon
Canals that connect central canals, allowing blood vessels and nerves to travel between osteons
Preforating (Volkmann’s) Canal
Undifferentiated cells that can develop into osteoblasts and contribute to bone growth and repair
Osteoprogenitor Stem Cells
Name the two types of bone development and be able to identify which bones in the body development by which type
Intramembranous ossification- bone develops from a fibrous membrane.
Bones formed: Flat bones of the skull, calvical, and some facial bones
Endochonral Ossification- Bone develops from a cartilage model.
Bones formed: Most bones of the body, including long bones, femur, humerus, and tibia
What does appositional growth of a bone refer to?
Bones growing in width
What is bone remodeling?
Ongoing replacement of old bone tissue by new bone tissue.
What cells are the remodeling unit teams?
Osteoclasts (break down bone) and Osteoblasts (build bone)
What are the two means by which bone remodeling is regulated?
Mechanical Stress and Hormonal Control
Name the type of bone fracture where the bone pierces the skin
A compound (open) fracture
What is it called when the bone does not pierce the skin?
A simple (closed) fracture
What is a greenstick fracture and when is the time in a persons life this type of fracture can occur?
An incomplete fracture where the bone bends and cracks, common in children due to their more flexible bones
Name a type of fracture that is caused from excessive twisting
A spiral fracture
Name the 4 steps to bone repair following a fracture.
- Hematoma formation- a blood clot forms at the fracture site
- Fabrocartilaginous Callus Formation- Soft callus forms as cartilage and collagen bridge between the break
- Bony Callus Formation- Soft callus is replaced with hard (spongy) bone.
- Bone remodeling - compact bone replaces spongy bone, restoring normal shape.
How long does bone take to repair following a fracture
Typically 6-8 weeks
The 3 classifications of joints based on structure, are fibrous, cartilaginous, and synovial. Describe a synovial joint and name what is contained in its cavity. Be able to identify the types of synovial joints and give examples
A freely movable joint where bones are separated by a joint cavity filled with synovial fluid, which lubricates and nourishes the joint.
Types and Examples: Ball-and socket- shoulder, hip hinge, knee, elbow pivot, Carpals, Tarsals
What are the 3 classifications of joints based on joint movement
Synarthrosis
Amphiarthrosis
Diarthrosis
Which muscles are striated and voluntary?
Skeletal muscles
Which muscles are striated and involuntary?
Cardiac muscle
Which muscles are non striated and involuntary?
Smooth muscles
What are 3 specialized functions of muscles in the body
Movement
Posture and Stability
Heat production
What are the organs in the skeletal system of the body?
Bones, cartilage, ligaments, and joints
The smallest functional unit of the muscle cell fibers is what?
Sacromere
What is the plasma membrane of a muscle cell called?
Sacrolemma
Name the connective tissue sheath that surrounds the sarcolemma of a muscle cell (fiber).
Perimysium
Name the connective tissue muscle that surrounds the entire muscle
Epimysium
The muscle fiber (cell) is composed of bundles of rod like structures called what?
Myofibrils
The fascicle is composed of bundles of what structures?
Muscle fibers (cells)
The muscle in its entirety is made of bundles of which structures?
Fascicles
Which type of muscle is made of cells that are multinucleate?
Skeletal muscle
Striations in muscle cells are caused by alternating ____ bands and ____ bands in the sarcomere, which collectively appear as stripes in the muscle. Which band appears darker and why? Which band appears lighter and why?
A bands, I bands
The A band appears darker because it contains thick myosin filaments, which block more light.
The I band appears lighter because it contains only thin actin filaments, which block less light.
Name the type of filament that is considered thin, and found by itself in the I bands, and with another filament in the A band.
Actin
Name the other filament found in the A band. It is considered thick
Myosin
During a muscle contraction, myosin heads grab actin and walk it towards the center of the sarcomere. When is ATP used in this process?
Cross-bridge detachment- ATP binds to the myosin head, causing it to release actin and detach from the binding site.
What is the ion that binds with troponin, which in turn allows tropomyosin to move away from the binding sites on actin so the myosin heads can grab the actin during a contraction?
calcium.
What is rigor mortis and what causes it?
Rigor mortis is the postmortem stiffening of muscles due to ATP depletion, preventing myosin from detaching from actin.
What is the endoplasmic reticulum of the muscle cell called? What mineral is stored there and released during a muscle contraction?
The endoplasmic reticulum of a muscle cell is called the sarcoplasmic reticulum (SR).
It stores and releases calcium during muscle contraction.
What allows all of the fibrils and sarcomeres of the muscle to contract simultaneously?
The T-tubules and sarcoplasmic reticulum (SR) coordinate calcium release, ensuring all fibrils and sarcomeres contract simultaneously.
Smooth muscle contract in a wave-like pattern called what?
peristalsis
Name the type of contraction when a muscle’s overall length changes during a contraction.
Isotonic contraction
Muscle shortening is an isotonic contraction is called ____ isotonic contraction. Muscle lengthening to its original relaxed state following a contraction is called ____ isotonic contraction.
Concentric
eccentric
When a muscle’s peak tension capabilities are not able to overcome the amount of resistance, the muscle length does not change. This is called a ____ contraction. (example: trying to life a grand piano)
Isometric contraction
Name the muscle group when there is an action performed by a dominate muscle with other muscles assisting.
synergists
Name the muscle group when one muscle relaxes while the other preforms its action
Antagonistic muscles: One muscle relaxes while the other preforms its action
Which muscle group is identified by muscles that work together to preform the same function?
Synergists
