skeletal system

skeletal system

provides structure, support, and protection to our organs and tissues and is responsible for range of functions including movement, mineral, and lipid storages, and blood cell formation

206

__ named bones in the body

organic and inorganic materials

Each bone is made up of both

collagen fibers and calcium phosphate crystals

give bones its strength and flexibility)

bones

involved in the regulation of lipids in the body

adipose tissue or fat

stored in the yellow bone marrow of certain bones such as femur and humerus

cartilage

makes an infants body more pliable, which is essential for navigating the birth canal

active cellular responses

faster healing process in children is partly due to their __, allowing them to recover quickly from injuries

growth plates

__ in childern’s bones enable them to increase in length til they are fully developed

long bones

most common type of bones in the body and are responsible for the support and movement of the body; long cylindrical shape with a shaft, and two ends

diaphysis

shaft

epiphyses

two ends

short bones

cube like shape found in the wrist and ankle; for stability and support of these joints

sesamoid bones

small and round, and are embedded in tendons near joints, protect the tendon from excessive wear and tear and improve the leverage of muscles

Wormian bones

are small bones that develop in the sutures of the skull.

➢ They are not present in all individuals, and their function is still unknown.

intrasutural bones

Wormian bones aka

Flat bones

are thin and flat and are found in areas of the body that require protection,

such as the skull, ribs, and sternum; site for muscle attachment

Irregular bones

have a unique shape that does not fit into any of the other categories. They are found in various parts of the body, including the vertebrae, facial bones, and pelvic bones

frontal

forms the forehead and the upper part of the eye sockets

supraorbital foramen/notch

frontal contains the __, a small opening above each eye that allows blood

vessels and nerves to pass through

glabella

smooth area between the eyebrows. It also houses the frontal sinuses

coronal suture

joins the frontal bone with the parietal bones

parietal bones

There are two __ that are located on the sides and superior of the skull, forming the majority of the cranial vault

sagittal suture

runs along the midline of the skull, separating the two parietal bones

temporal bones

Two __ are situated on the sides of the

skull.

zygomatic process

extends forward to articulate with the zygomatic bone (cheekbone).

external acoustic meatus/canal

the passage

leading to the middle ear

styloid process

a slender projection, and the mastoid process is a bony prominence behind the ear

squamous suture

connects the temporal bone with the parietal bone on the side of the skull

occipital bone

found at the back of the skull

large foramen magnum

occipital bone contains the __, through which

the spinal cord passes

Sutural bones

also known as Wormian bones, are small extra bones that occasionally appear within the sutures of the skull; considered variations of normal bone development.

sphenoid bone

__ is located at the base of the skull.

sella turcica

sphenoid bone includes the __, which houses the pituitary

gland.

ethmoid bone

__ is situated between the eyes

crista galli

a triangular process that projects upward and supports the cribriform

superior, intermediate, and inferior nasal conchae

o There are __ that form the walls of the nasal cavity that

arise from the ethmoid and maxillary bones.

maxillary sinuses

Two maxillae bones form the upper jaw

that house the

infraorbital foramen

openings below the eye socket

incisive foramen/fossa

located on the roof of the mouth

cheekbones

Two zygomatic bones form the

temporal process

completes the zygomatic arch from the temporal bone

mandible or lower jawbone

_, is the only movable bone of the skull

body

forms the chin or mental protuberance mandible

ramus

connects to the skull

mental foramen

small openings on the front of the mandible that allow blood vessels and nerves to pass through

Two nasal bones

form the bridge of the nose

Two lacrimal bones

form the medial wall of the orbit and include the lacrimal fossa

Two palatine bones

form the posterior part of the hard palate

vomer

a thin, flat bone located in the nasal cavity, dividing it into two sides

hyoid bone

U-shaped bone located in the neck, just above the larynx.

It supports the tongue and provides attachment points for certain muscles

33 vertebrae

vertebral column, also known as the spine, is composed of __ that are separated by intervertebral discs

cervical vertebrae

specialized to allow a wide range of

motion for the head and neck

atlas

first cervical vertebra is called the __ (C1), which holds the world (head),

axis

second is called the __ (C2), which causes

rotation around a dense body

thoracic vertebrae

articulate with the ribs and provide

support and protection for the thoracic

organs

downward pointing

thoracic vertebrae spinous process is __, making the vertebrae appear as

a giraffe

lumbar vertebrae

the largest and strongest vertebrae; They support the weight of the upper body and provide flexibility and stability to the spine.

fat and short

lumbar vertebrae spinous process is __, making the vertebrae appear as a moose

five fused vertebrae

sacrum is composed of __and forms the posterior wall of

the pelvis

sacral foramina

are openings in the sacrum that allow for the passage of

nerves and blood vessels

coccyx, or tailbone

__, is composed of three to five fused coccygeal vertebrae

7 pairs of true ribs (Ribs 1-7)

directly attach to the sternum via their own

costal cartilage

3 pairs of false ribs (Ribs 8-10)

costal cartilage indirectly connects to the sternum, attaching to the cartilage of the rib above

2 pairs of floating ribs (Ribs 11-12)

do not have any attachment to the sternum, only connecting to the vertebrae at the back

sternum, or breastbone

, is a flat bone located in the center of the chest.

the manubrium, the sternal body, and the xiphoid process

sternum, or breastbone consists of three parts:

jugular notch

concave indentation at the superior edge of the manubrium, between the clavicular articulations

PECTORAL GIRDLE

consists of the scapula and clavicle. It holds the arms to the thoracic trunk

acromion process

forms the tip of the shoulder

coracoid process

serves as an attachment point for muscles and ligaments;

glenoid cavity

articulates with the humerus to form the shoulder joint

spine of the scapula

bony ridge on the posterior side

clavicle, or collarbone

a long bone that connects the scapula to the sternum. It helps stabilize the shoulder and provides attachment points for various muscles

humerus

the long bone of the upper

arm

head

articulates with the glenoid cavity of the scapula

greater tubercle and the lesser

tubercle

part of humerus that serve as attachment points

for muscles;

deltoid tuberosity

where the deltoid

muscle attaches

trochlea and capitulum

involved in the articulation of the elbow joint.

radius

one of the two bones of the

forearm. It extends from the elbow to the

wrist on the thumb side

head of the radius

which articulates with

the capitulum of the humerus

radial tuberosity

where the biceps

muscle attaches

radial styloid process

bony projection at the wrist.

ulna

other bone of the forearm, running parallel to the radius

olecranon process

forms the bony prominence of the elbow

ulnar styloid process

, a projection at the wrist

Eight carpal bones

__ form the wrist joint. These bones are arranged in two rows, with four bones in each row

scaphoid bone

largest in the proximal row and is located on the lateral side of the wrist. It

articulates with the radius bone

lunate bone

crescent-shaped and sits just medial to the scaphoid bone. It is one of the

most important bones in the wrist and is a key player in wrist movements

triquetral bone

pyramid-shaped and located on the medial side of the wrist. It is

involved in wrist extension and flexion

pisiform bone

the smallest in the proximal row and is situated on the palmar side of the wrist. It plays a crucial role in transmitting force from the wrist to the hand

trapezium bone

located on the lateral side of the distal row and articulates with the

thumb

trapezoid bone

located medial to the

trapezium bone and is involved in hand

movements.

capitate bone

largest in the wrist and is situated at the center of the distal row. It forms the base of the third metacarpal bone and is an important link between the wrist and the hand

hamate bone

located on the medial side of the wrist and has a hook-like process called the hamulus. It serves as an attachment site for ligaments and muscles and helps support the hand during gripping

metacarpal bones

long bones that form the framework of the hand and are numbered 1-5 from the thumb to the little finger.

14 phalanges

__ form the fingers and are divided into three sections per finger, the

proximal phalanx, the middle (intermediate) phalanx, and the distal

phalanx, except the thumb which only has two.

pelvic girdle

includes the coxal bones and the sacrum

Hip bone

also known as the coxal bone, is formed by the fusion of three bones: the ilium, ischium, and pubis

acetabulum

cup-shaped socket on the lateral surface of the hip bone, which articulates with the head of the femur to form the hip joint