The Skeleton, Muscles and Movement Flashcards
what do the skeleton and muscles make up?
the musculoskeletal system
what controls the musculoskeletal system
the nervous system
endoskeleton is made of
bone and cartilage
2 parts of the endoskeleton
axial skeleton
appendicular skeleton
axial skeleton
skull, vertebrae, sternum and ribs
appendicular skeleton
bones of arms and legs, pelvic and pectoral girdles
how many bones in the skull
22
cranium
bones are protected by fixed joints called sutures
function of cranium
protects brain, eye and ear
jaws
fixed upper jaw and moveable lower jar
function of jaws
holds the teeth
what does the vetebral column consist of?
33 bones held together by ligaments
what separate vertebrae?
discs of cartilage
function of discs
allow friction-free movement and act as shock absorbers
is the backbone flexible
yes, as the vertebrae can move slightly
function of the vertebral column
encloses and protects the spinal cord
all of the vertebrae
6 cervical 12 thoracic 5 lumbar 5 sacral 4 caudal
cervical
neck
function of cervical
support for skull
thoracic
chest
function of thoracic
allow movement of ribs
lumbar
small of back
function of lumbar
strong support for abdominal region
function of sacral
fused together, strong support for hip girdle
function of caudal
fused to form coccyx
how do discs protect the vertebrae
they act as shock absorbers
type of process for attachment of muscles
transverse process
3 parts of a single vertebra
neural canal
neural spine
articulation surface
neural canal
spinal cord lies here
neural spine
for attachment of muscles
how many ribs
12 pairs
each pair of ribs
attached to a separate vertebra
back side
dorsal side
front side
ventral side
first 7 pairs of ribs at the front
attached directly to the sternum
ribs 8-10 at the front
attached to the sternum indirectly by cartilage
ribs 11-12 at the front
not attached to the sternum (floating ribs)
2 girdles
pectoral girdle
pelvic girdle
2 parts of the pectoral girdle
scapula (shoulder blade) and clavicle (collar bone)
how is the pectoral girdle attached to the vertebral column
by muscles
how is the arm attached to the pectoral girdle
ball and socket joint
what does the pelvic girdle consist of?
6 fused bones attached to the sacrum
the pelvic girdle surrounds…
a hollow cavity called the pelvis
how is the leg attached to the pelvic girdle
by a ball and socket
fore-limb
arm
hind-limb
leg
5 functions of the skeleton
support protection movement production of blood cells stores calcium
support of the skeleton
the rigid skeleton holds the body upright and gives it shape, forms the framework of the body
protection of the skeleton
skull protects the brain
backbone protects spinal cord
ribcage protects heart and lungs
movement of the skeleton
muscles attached the bones by tendons, when muscles contract, they pull bones causing movement
production of blood cells by the skeleton
red and white blood cells and platelets are made in red bone marrow
2 skeletal tissues
cartilage
bone
what is cartilage?
a living tissue, consisting of cells and protein fibres embedded in a rubbery matrix
describe cartilage
strong and flexible
where is cartilage found 3
pinna of ear
trachea
intervertebral discs
what is bones
bone is a living tissue, much harder than cartilage, most of the adult skeleton is comprised of bone
long bones
shaft and expanded cells. has a central cavity called the medullary cavity surrounded by compact bones, the ends have spongy bone surrounded by compact bone and a layer of cartilage
3 parts of a long bone
compact bone
spongy bone
bone marrow
compact bone
a tough, dense outer layer of bone
what does compact bone consist of?
bone cells called osteoblasts embedded in a matrix of protein fibres (collagen), hardened with calcium salts and phosphates.
what are bone cells supplied with?
blood vessels and nerve fibres
function of compact bone
gives strength and rigidity
spongy bone
found in the ends of long bones
what does spongy bone consist of?
bony bars and plates with spaces filled with bone marrow
function of spongy bone
gives strength and rigidity without adding too much weight
2 types of bone marrow
red marrow
yellow marrow
red marrow found in
ribs, pelvis, vertebrae and spaces between spongy bone
function of red marrow
produced red blood cells, white blood cells and platelets
yellow marrow
inactive marrow
where is yellow marrow found
in the medullary cavity of long bones
function of yellow marry
stores fate
the skeleton of the human embryo is first composed of
fat
replacement by bone in embryo
in the 8th week - ossification
bone-forming cells
osteoblasts
function of osteoblasts
secrete protein fibres which form a matrix in which the bone cells become embedded
how do the protein fibres become hardened?
with the addition of calcium salts
function of protein fibres
give the bone flexibility
function of calcium salts
give the bone strength
when do osteoblasts become dormant?
when embedded in the hardened bone material and they are known as osteocytes
growth in length of bone
occurs in growth plate (made of cartilage)
where is the growth plate found?
between the head and the shaft of the bone
what happens in the growth plate?
cartilage is continuously made and converted into bone by osteoblasts
growth stimulated by
growth hormone from pituitary gland
in adulthood, what happens to the growth plate?
it is replaced by bone and the bone no longer increases in length - this determines the height of the person
does bone formation stop in adulthood?
no, throughout life, bone is continually broken down and replaced again
osteoclasts
cells that break down bone and release calcium into blood
osteoblasts
form new bone
continued renewal of bone depends on
exercise, diet, age and hormones (sec and growth)
effect of physical activity on bone
bones become thick and strong when stressed
lack of stress on bones
causes them to become thin
calcium and vitamin D
essential in the diet, especially up to age 35 where bone density reaches its maximum
osteoporosis
a disorder of the musculoskeletal system where bone density decreases (porous bones)
what is osteoporosis
a loss of bone cells, collagen and minerals from bone - causes bones to become brittle and break easily
what causes osteoporosis
lack of exercise, lack of calcium, genetic makeup, ageing (fall of oestrogen at menopause
3 forms of treatment for osteoporosis
weight bearing exercise
increased calcium and vitamin D in diet
hormone treatment (HRT - oestrogen)
prevention of osteoporosis
diet rich in calcium and vitamin D
exercise to stress the bones
where 2 bones meet
join
joints are classified by
the movement that they allow
3 types of joints
immovable joint
slightly movable joint
freely movable or synovial joint
immovable joint
bones fused together
where can you find immovable joints
skull, bones in pelvic girdle
function of immovable joints
protection and strength
slightly moveable joint found
between vertebrae
slightly moveable joint in vertebrae
vertebrae held by ligaments and separated by discs of cartilage
function of slightly moveable joint
allows limited movement but still protects the spinal nerves
4 types of freely movable or synovial joint
ball and socket
hinge
gliding
pivot
ball and socket joint
found in hip and shoulder
function of ball and socket joint
allows movement in 3 planes
hinge joint
in elbow and knee
function of hinge joint
allows movement in one place
gliding joint
in wrist and ankle
pivot joint
in neck
in a synovial joint: ends of bones
enclosed in a fibrous capsule, part of the capsule is modified to form ligaments
ligaments
hold bone to bone
in a synovial joint: inside of capsule
lined with synovial membrane which secretes synovial fluid
synovial fluid
acts as a lubricant, preventing friction in the joint during movement
in a synovial joint: ends of bone covered
covered with a layer of smooth cartilage (articular cartilage). helps to prevent friction and acts as a shock absorber
arthritis
a skeletal disorder where there is inflammation or swelling in a joint
1 common form of arthritis
osteoarthritis
causes of arthritis
cartilage covering the ends of the bones is worn down due to wear and tear, injury, disease or age
bone underneath enlarges and more synovial fluid forms, joint becomes swollen and stiff
prevention of arthritis 3
reduce damage to joints by;
avoiding running on hard ground
using proper footwear when running
avoid too much strain and injury of joints
treatment of arthritis 4
rest the joint
exercise to retain mobility
anti-inflammatory drugs to reduce the swelling
replacement of joint by surgery
muscles
the contractile tissues of the body - bring about movement
3 types of muscles
smooth
skeletal
cardiac
2 other words for smooth muscle
unstriped or involuntary muscle
smooth muscle causes
slow, involuntary movements
smooth muscle found in
walls of arteries, veins, gut, uterus, bladder etc,
skeletal muscle aka
striped or voluntary muscle
skeletal muscle causes
quick, voluntary movements
skeletal muscle found in
attached to skeleton eg. biceps, triceps
cardiac muscle
contracts rhythmically without getting fatigued
cardiac muscle found in
wall of heart
skeletal muscles connected to bone by,
tough, inelastic tendons
antagonistic muscles
pairs of muscles that have opposing effects
1 pair of antagonistic muscles
biceps and triceps
bicep contracts tricep relaxes
raises forearm (flexor)
tricep contracts bicep relaxes
lowers forearm (extensor)
