LO1 LS1 - Describe the Skeletal System According to its Functions, Bone Structure, Descriptive Terms and the Divisions of the Skeletion

All information taken from bright space content.

how many bones are there in the human body

206 bones

what is a bone

a hard, dense connective tissue that forms most of the adult skeleton, the support structure of the body

what can be found in the areas of the skeleton where bones move (ex: the ribcage & joints)

cartilage

what is the structural function of bones

provides an internal framework and support

bones function as a _____ for soft tissues and vital organ

protection

how do bones protect vital organs

bones act like a hard shield around soft, delicate internal organs

what does the skull bone protect

protects the brain, eyes, and ears

what does the rib cage bone protect

protects the heart and lungs

what does the pelvis protect

protects the lower abdominal and internal reproductive organs

bones function as a ____ attachment (__ attach to bones)

muscle

what is the function of bones in hematopoiesis

provide the internal environment that houses red bone marrow where new blood cells are made

what is hematopoiesis

the process of blood cell formation

where are most blood cells formed in the body

in the red bone marrow

where does hematopoiesis occur in adults

in the vertebrae, ribs, sternum, pelvis, proximal humerus & femur, skull, and clavicle

bones function as a ____ of fat and calcium

storage

what is the inorganic salt stored in bones

mostly calcium phosphate (CaPO4)

what are the two types of bone tissue

compact and spongy bone

what is cartilage

a semi-rigid form of connective tissue

what are the primary functions of cartilage in joints

it provides flexibility and smooth surfaces for movement

the skeletal system performs what critical functions for the human body

• Supports the body

• Facilitates movement

• Protects internal organs

• Produces blood cells

• Store and releases minerals and fat

what is the first arrow pointing to

the outer surface of bone

what is the second arrow pointing to

red marrow

what is the third bone pointing to

yellow marrow

what are the two types of bone marrow

yellow marrow and red marrow

what does yellow marrow contain

fat

what does the fat in yellow marrow serve as

a source of energy

what takes place in the red marrow

hematopoiesis (the production of blood cells)

what is produced in the red marrow

red blood cells, white blood cells, and platelets

what gives bones their hardness and strength

hydroxyapatite crystals

what gives bones their flexibility so that they are not brittle

collagen fibers

what are the four types of cells found within bone tissue

osteoblasts, osteocytes, osteogenic cells, and osteoclasts

what is the function of osteoblasts

bone formation / bone forming cells (builders)

where is the location of osteoblasts

in the growing portions of bone, including periosteum and endosteum

what is the function of osteocytes

maintain mineral concentration of matrix

where is the location of osteocytes

entrapped in matrix

what is the function of osteoclasts

bone resorption

where is the location of osteoclasts

on bone surfaces and at sites of old, injured, or unneeded bone

what is the primary cell of mature bone and the most common type of bone cell

osteocyte

each osteocyte is in a space called a ___ and is surrounded by bone tissue

lacuna

what do osteocytes help maintain

the existing bone and keep the bone alive

what cell is responsible for bone resorption or breakdown

osteoclast

the ongoing balance between osteoblasts and osteoclasts is responsible for what

the constant but subtle reshaping of bone

what is the cell in the image and its function

osteocyte & maintains bone tissue

what is the cell in the image and its function

osteoblast & forms bone matrix / builders

what is the cell in the image and its function

osteoclast & resorbs bone / bone dissolving cells ‘clean up’ old bone

what is the difference between osteoblasts vs osteocytes

osteoclasts BREAK DOWN old or damaged bone, while osteoblasts BUILD new bone tissue

what is the structure of compact bone

hard and dense

how is compact bone structurally arranged

tightly packed tissue with no spaces in circular osteons

where is compact bone located

under the periosteum & in the walls of the diaphysis (shaft) of long bones

what is the function of compact bone

provides support & strength of long bones

what is spongy bone also known as

cancellous bone

what cell type do both compact and spongy bone contain

osteocytes (housed in lacunae)

how are osteocytes arranged in spongy bone compared to compact bone

they are found in a lattice-like network of trabeculae, not in concentric circles

what are trabeculae

A lattice-like network of matrix spikes

how do trabeculae develop to provide structural strength

they form along lines of stress

what is the structural benefit of the spaces in spongy bone

they make bones lighter so muscles can move them more easily

what tissue fills the spaces of some spongy bones

red marrow

what vital process occurs inside the red marrow of spongy bone

hematopoiesis (the formation blood cells)

spongy bone consists of what plates and what does it form

thin boney plats and form a mesh like framework with spaces

what does the spongy bone form the interior of

small bones, skull, and epiphysis (ends) of long bones

what is the function of spongy bone

reduces weight of bones and contains red bone marrow

what marking is described as having a prominent rounded surface

head (ex: head of femur)

what marking is described as having a flat surface

facet (ex: vertebrae)

what marking is described as a rounded surface

condyle (ex: occipital condyle)

what marking is described as protruding

protuberance (ex: chin)

what marking is described as having a prominence feature

process (ex: transverse process of vertebra)

what marking is described as having a sharp process

spine (ex: ischial spine)

what marking is described as having a small, rounded process

tubercle (ex: tubercle of humerus)

what marking is described as having a rough surface

tuberosity (ex: deltoid tuberosity)

what marking is described as a ridge

crest (ex: iliac crest)

what marking is described as having an elongated basin

fossa (ex: mandibular foss)

what marking is described as a hole through bone

foramen (ex: foramen magnum in the occipital bone)

what marking is described as an opening into canal

meatus (ex: external auditory meatus)

what marking is described as an air-filled space in bone

sinus (ex: nasal sinus)

what does a long bone consists of

1 diaphysis and 2 epiphyses

what is the diaphysis of a long bone

it is the shaft, made of compact bone, and provide strength

what is the epiphyses of a long bone

it’s the ends, made of spongy bone, and contains red bone marrow

what are examples of a long bine

humerus & femur

what is the medullar cavity of a long bone

long hollow tube in the center of the diaphysis

what is the medullary cavity of a long bone filled with

yellow bone marrow which stores fat

what is the axial skeleton/what does it form

the vertical, central axis of the body

what is included in the axial skeleton

all bones of the head, neck, chest, and back

what major organs are protected by the axial skeleton

the brain, spinal cord, heart, and lungs

what are the three main parts of the axial skeleton

the skull, the vertebral column, and the thoracic cage

how many bones form the skull

22 bones

what bone is associated with the head besides the skull bones

the hyoid bone

the vertebral column consists of how many bones

24 bones (each called a vertebra), plus the sacrum and the coccyx

what does the thoracic cage include

12 pairs of ribs and the sternum

What is the sternum

the flattened bone of the anterior (front) chest

what does the appendicular skeleton include

all bones of the upper and lower limbs, plus the bones that attach each limb to the axial skeleton

what are the three regions of the upper limb

the arm, the forearm, and the hand

where is the arm located

between the shoulder and elbow joints

where is the forearm located

between the elbow and wrist joints

where is the hand located

distal (further away) to the wrist

how many bones are in each upper limb

30 bones

what is the single bone of the upper arm

the humerus

what are the two paired bones of the forearm

the ulna (medially) and the radius (laterally)

which forearm bone is on the medial side

the ulna

which forearm bone is on the lateral side

the radius