Biology - Joint Movements Flashcards
osteocyte
bone cell surrounded by matrix
Red bone marrow functions in the formation of…
red and white blood cells and platelets
The microscopic bony chambers that house mature bone cells are called
lacunae
the salt that form tiny crystals in the intercellular matrix of bone tissue consist largely of
calcium phosphate
which of the following bones is not included within the lower limb
ulna
the joints between the vertebrae of the backbone are best described as
slightly movable
which of the following is NOT included in the appendicular skeleton
vertebral column
what are the cells responsible for removing excess bone tissue after the fracture repair process called?
osteoclasts
which of the following increases the risk of developing osteoporosis?
low intake of dietary calcium, lack of physical exercise, frequent use of alcohol
true or false- the appendicular skeleton consists of the parts that support and protect the head, neck, and trunk
false
true or false- vitamin D is needed for the proper absorption of calcium in the small intestine
true
true or false- osteocytes become osteoblasts when they are completely surrounded by bony matrix
false
what is the difference between red and yellow bone marrow?
yellow bone marrow stores fat. Red bone marrow occupies the cavities of bone for infants. over time this is replaced by yellow bone marrow. red bone marrow also creates red and white blood cells and platelets
what are the 4 functions of bone
support and protect organs, body movements (bone and muscles interact as levers), blood cell formation, storage of inorganic salts
what is a joint
union of two or more bones
what are the 3 types of joint (and define them)
fibrous- between bones of skull- no movememnt
cartilaginous- between bodies of vertebrae- some movement
synovial- lots of movement
what are the 6 types of synovial joints?
ball and socket- shoulder
conclyoid- between metacarpals and phalanges
gliding- wrists and ankles
hinge- elbow
pivot- ulna
saddle- between carpal and metacarpal of thumb
intramembranous vs. endochondral + examples
intramembranous- originate sheetlike layers of connective tissue
endochondral bones- begin as masses of cartilage that bone tissue later replaces
steps of how a bone repairs itself after a fracture
- blood escapes from broken vessel and form a blood clot
- spongy bone forms close to developing blood vessels
- bony callus replaces fibrocartilage/spongy bone
- osteoclasts remove extra bone tissue and restore new bone structure
the impulse that triggers a contraction travels deep into a muscle
transverse tubules
a sarcomere is best described as
a unit within a myofibril
myofibrils are composed primarily of
actin + myosin
neurotransmitters are stored in vesicles
motor neuron endings
during muscles relaxation, the enzyme cholinesterase causes acetylcholine to
decompose
a muscle cramp is likely due to a lack of
ATP
a motor unit includes
several muscle fibers and one motor neuron
Rigor mortis that occurs in skeletal muscles a few hours after death is due to
lack of ATP, which prevents muscle relaxation
when a muscle undergoes atrophy in response to disuse
there is a reduction in caprillary networks, the number of mitochondria decreases, the size of actin and myosin filaments decreases
true or false- endomysium separates individual muscle fibers
true
true or false- a motor neuron and the muscle fibers that it controls constitute a motor unit
true
during muscle contraction, calcium irons combine with tropomyosin and this exposes active sites for cross-bridge formation
false
what are the 3 types of muscle tissues and the differences between them
cardiac- only in heart, involuntary, striated
skeletal- voluntary, striated, attached to tendon/bone
smooth- nuclei, voluntary, found in blood vessels. looks like an eye, not striated
what is neuromuscular junction
the point of communication between nerve cells and muscles cells
sliding filament theory
describes the process of muscle contraction
role of ATP during muscle contraction
- atp turns into ADP when a phosphate group is removed
- energy is produced to release the myosin head in a position to attach to the actin filament
main steps of muscle contraction
- motor neurons release acetychcyine into synoptic cleft
- acetycholine diffuses across syhoptic cleft, combines protein
- calcium binds to troponin
what is acetylcholine and a muscle impulse
acetylcholine- neurotransmitter that stimulates skeletal muscle to contract
muscle impulse- muscle contractions triggers and nerves stimulate a muscle
6 main steps of muscle fiber relaxation
- enzyme decomposes
- calcium ions are transported
- atp causes a link between actin and myosin
- troponin/tropomyosin interact to block binding on actin
- muscle fibers relax
- repeat
what is malignant hyperthermia
severe reaction to drugs used for anesthesia
what do the I band look like
lighter part
A band
darker part
sarcomere
all bands - two dark and two light
2 line
line in between?
