Bio 5 Exam 2 Sierra College

True, false, and floating ribs

True ribs - #1-7, attach directly to sternum by costal cartilage False ribs - #8-10, attach indirectly to sternum by costal cartilage Floating ribs- #11 &12, do not attach anteriorly at all

Third class lever - most common

a force is applied between the resistance and the fulcrum. (speed & distance). Hammer pulling nail. 1. load - effort - fulcrum 2. always mechanical disadvantage 3. Examples: flexing forearm A.Load - forearm B.Effort - biceps brachii inserting on radius C.Fulcrum - elbow

fontanels

anterior posterior mastoid sphenoid

Fontanels

are fibrous CT connecting cranial bones in an infanti. Functions: 1.Allow infant's head to be compressed slightly during birth 2.Allows brain growth in the fetus and infant

Atlas C-1

no body, anterior & posterior arches and two transverse foramen

Axis C-2

odontoid process or dens develops from the body of the atlas

Synergist

- An "assistant" that adds force to a movement or helps stabilize

Compact bone

- Dense outer layer - Appears smooth and solid - Concentric rings called osteons -walls of bones

Long Bones

- Longer than wide - Mostly compact bone with spongy at the ends - Examples: Femur, humerus, phalanges

Antagonist

- Stretches and stabilizes in support of the action of the agonist (biceps/triceps)

Sesamoid bones

- Type of short bone that forms in a tendon - Example: Patella - knee cap

Hormonal control

- When blood calcium is low- PTH activates osteoclasts to breakdown bone to release Ca2+ - When blood calcium is too high -Calcitonin activates osteoblasts to sequester Ca2+ and deposit bone

Connective Tissue Wrappings

- bind, support and insulate the muscle.

Cartilaginous

- bones connected by cartilage i.Synchondrosis - united by hyaline cartilage 1.Examples: 1strib to manubrium, epiphyseal plates2.Synarthrosis ii.Symphysis - united by fibrocartilage 1.Examples: Intervertebral discs, pubic symphysis 2.Amphiarthrosis

Fibrous

- bones connected by dense connective tissue i. Sutures - found in skull bones, bones interlock and are held together by very short fibers 1.Synarthrosis ii.Synostosis- fibers of sutures completely ossify and bones fuse 1.Synarthrosis 2. Examples: frontal, mandible, os coxae iii. Syndesmosis - bones connected by ligaments 1. Degree of movement depends on length of ligament (amphiarthrosis) 2. Examples: distal tibiofibular joint, interosseousmembrane b/t radius and ulna iv. Gomphosis - tooth held in socket by periodontal ligament1.Synarthrosis

Medullary cavity

- cavity of the diaphysis. Contains: 1.Red marrow - for blood cell formation in infants 2.Yellow marrow -(mostly fat) in adults

Appositional growth

- growth in thickness (width) 1.Osteoblasts deposit bone to the outer surface below the periosteum 2.Osteoclasts remove bone from the inner surface, enlarging the medullary cavity

Endochondral ossification

- hyaline cartilage is replaced by bone - Bones are modeled in hyaline cartilage first during development -Examples: all other bones

Direct

- muscle attaches immediately to bone, e.g., intercostals

Indirect

- muscle attaches to tendons (common) or aponeuroses (e.g., galea aponeurosis, aponeurosis of the external oblique)

mechanical advantage

- power lever, load lifted is greater than the applied effort but the load only moves a short distance Load is closer to the fulcrum than the effort

mechanical disadvantage

- speed lever, allows load to be moved rapidly and over a greater distance however requires more effort to overcome load Effort is closer to fulcrum than the load

Femur

- thigh bone a.Largest and strongest bone of the bod

Osteoarthritis

--degenerative condition related to the aging process, caused by "wear and tear" on the joint a. As one ages, cartilage is destroyed quicker than it is replaced b.The exposed bone ends thicken, forming bone spurs that restrict movement c.Joints most affected are the cervical and lumbar vertebrae, fingers, knuckles, knees, and hips

Mechanical stress

-Bone is deposited in response to stress caused by muscle pull, weight, and gravity -Piezoelectric effect -when minerals are stressed they produce electrical voltage which stimulates osteoblasts to deposit bone

Irregular bones

-Complicated shape -Does not fit into other bone classification categories -Example: Vertebrae, facial bones, os coxa (hip)

Epiphyseal plate

-Disc of hyaline cartilage at the epiphysis-diaphysis junction -Allows bone to grow in length

Short bones

-Generally cube-shape - Contain mostly spongy bone with a thin outer layer of compact bone - Examples: Carpals, tarsals

Articular cartilage

-Hyaline cartilage covering the external surface of the epiphyses -Decreases friction at joint surfaces

Fractures: linear vs. transverse

-Linear. A fracture line that runs parallel to the bone's axis. -transverse fracture is when the fracture line is perpendicular to the shaft (long part) of the bone.

Agonist/prime mover

-Main muscle responsible for the action

Epiphyseal line

-Remnant of the epiphyseal plate in adults -Thin line of compact bone

Spongy bone

-Small needle-like pieces of bone (trabeculae) -Many open spaces -(aka trabecular or cancellous bone) ◦Open network of plates ◦Surrounds the medullary cavity ◦Medullary cavity consists of bone marrow

Flat bones

-Thin and flattened, slightly curved -Thin layers of compact bone around spongy bone -Examples: Skull bones, ribs, sternum, mandible

Rheumatoid arthritis

-autoimmune disease in which the immune system attacks joint tissue a.Inflammation causes scar tissue to form and joints to fuse, resulting in bent deformed joints b.Affects 3X as many women as men c.Affects joints bilaterally, and off and on

Intramembranous ossification

-bone develops within a fibrous membrane -Examples: skull bones, clavicle, mandible

Synovial

-bones are connected by a joint capsule surrounding a fluid filled cavity i.All are diarthroses (freely movable)

Fractures: complete vs. incomplete

-complete fracture, the bone snaps into two or more parts -incomplete fracture, the bone cracks but does not break all the way through

Fractures: compound vs. simple

-compound fracture: where the bone is not only broken completely through and separated, but one end of the broken bone is sticking through the skin -simple: often just a crack in the bone

Secondary curvature

-develop later (concave posterior) a.Cervical b.Lumbar

Primary curvature

-direction of fetal curvature, are present at birth (convex posterior) a.Thoracic b.Sacral

Fractures: nondisplaced vs. displaced

-displaced fracture, the bone snaps into two or more parts and moves so that the two ends are not lined up straight. -non-displaced fracture, the bone cracks either part or all of the way through, but does move and maintains its proper alignment.

Epiphysis

-ends of the bone -Composed mostly of spongy bone -Contains red marrow

Arthritis

-inflammation of the joints i. Symptoms include stiffness, swelling and pain ii.Affects women more than men

Knee injuries

-knee is very vulnerable to horizontal forces 1. torn meniscus- medial meniscus and tibial collateral ligament usually tears from lateral force 2. torn ACL- results from quick change in direction or twisting of the knee

Bone Remodeling

-occurs throughout one' s life -Involves both new bone formation and bone reabsorption(osteoblasts and osteoclasts)

Growth hormone

-secreted by anterior pituitary glanda Most important stimulus of epiphyseal plate activity during childhood Hypersecretion = gigantismii. Hyposecretion = pituitary dwarfism

Articulations

-site where two or more bones meet

Canaliculi

-tiny canals that radiate from the central canal to lacunae

Relationship between forces and distance

-trade-off between effort input and distance or speed of movement Effort X Effort distance = Load X Load distance

Bone Repair

1. Blood clot or hematoma forms 2. Internal calculus of spongy bone and external calculus of cartilage and bone forms 3. Spongy bone replaces calculus and unites the broken ends 4. Overtime bone will be remodeled

Steps of endochondral ossification (6):

1. Bone collar forms around diaphysis 2. Chondrocytes within the diaphysis calcify and deteriorate 3. Periosteal bud infiltrates the diaphysis and spongy bone forms 4. Osteoclasts form the medullary cavity 5. Secondary ossification centers appear in the epiphyses 6. Cartilage remains only at the epiphyseal plates and articular cartilage

Factors contributing to osteoporosis

1. Decrease in estrogen or testosterone levels 2. Insufficient bone density to begin with -density peaks at ~30 years of age and declines thereafter 3. Genetics - determines tendency to accumulate bone mass 4. Poor diet - insufficient calcium, vitamin D, A, & C5.Lack of exercise6.Smoking -- reduces ability to absorb calcium

Depressions or openings

1. Fossa- shallow depression 2.Sulcus- groove 3.Meatus or canal- passageway 4.Fissure- slit like opening, crack 5.Foramen- opening through a bone 6.Sinus- cavity within a bone 7.Neck- narrowing of the bone below the head

Three components of lever systems:

1. Fulcrum- pivot point which the lever moves on; the joint 2.Load - resistance; either the bone itself or any other weight 3.Effort - force applied by a muscle to move a load. It is at the point of insertion on the bone.

Treatment of osteoporosis

1. Hormone replacement therapy 2. Fossamax, Boniva, and other drugs - inhibit osteoclast activity 3. Newer drugs - stimulate osteoblasts 4. Exercise - promotes bone deposit 5. Calcium and vitamin D supplements

Bone Remodeling occurs to:

1. Maintain proper proportions 2. Maintain blood calcium homeostasis 3. Repair injured bone or increase bone strength

Other accessory structures found in some synovial joints:

1. Menisci- fibrocartilage pad that improves the fit between bones a.Examples: TMJ and knee 2. Bursa - fibrous bag filled with synovial fluid a. Found where ligaments, tendons or muscles may rub and cause friction 3. Tendon sheath - elongated bursa that wraps around tendons, reduces friction

Types of synovial joints and movements allowed:

1. Nonaxial-- does not rotate on an axis, moves on a plane a. gliding joints - bones slide on each other i. Between carpals & tarsals ii. Thoracic vertebrae and ribs 2. Uniaxial- rotating on one axis a. hinge joint- flexion & extension i.Elbow ii. Between phalages 3. Biaxial- movement on two axis, back and forth, side to side a. ellipsoidal joint- oval projection in deep depression i.Metacarpals and phalanges b.Saddle - multiangular motion but not full rotation i. 1st metacarpal and trapezium 4.multiaxial - movement in all axis a. ball and socket- spherical head fits into rounded socket i.Shoulder ii.Hip

Steps of intramembranous ossification (5):

1. Ossification center appears within the membrane 2. Mesenchymal cells differentiate into osteoblasts 3. Osteoblasts secrete bony matrix between blood vessels 4. Fibrous CT becomes periosteum 5. Compact bone collar forms deep to periosteum

Bone cells consist of (4):

1. Osteoprogenitor cells 2. Osteoblasts 3. Osteocytes 4. Osteoclasts

Projections or elevations

1. Process- bump or projection of the bone 2. Tuberosity- rough projection 3. Tubercle- small rounded projection 4. Crest- prominent ridge 5. Spine- sharp, slender or pointed 6. Head- expanded end 7. Condyle- smooth, rounded articular process 8. Facet- small, flat 5.12 in text

What is osteoporosis? Who is at risk?

1. Reduction in bone mass resulting in loss of bone density 2. Occurs when reabsorption of bone outpaces deposit of bone 3. Results in porous bones that are light and fragile 4. Both men and women are at risk, however tends to effect postmenopausal women

Basic features of synovial joints

1. articular cartilage- on the ends of epiphysesa. Absorbs compression and reduces friction 2. joint capsule- surrounds joints. Composed of: a. fibrous capsule- dense irregular CT, continuous with the periosteum b. synovial membrane - inside lining of joint capsule, secretes synovial fluid 3. joint cavity - space filled with synovial fluid 4. synovial fluid a. Functions: i.reduces friction ii.nourishes chondrocytes iii.shock absorber 5. reinforcing ligaments- additional strength and support a. Extracapsular- outside joint capsule b. Intracapsular- inside joint capsule

Abnormal curvatures

1. kyphosis- exaggerated thoracic 2. lordosis- exaggerated lumbar (swayback) 3. scoliosis- lateral curvature (frontal plane)

When a muscle is attached to the skeleton, the site of connection will determine:

1. range of movement 2. speed of movement 3. force of movement

Closure of the epiphyseal plate

1.At maturity chondrocyte division slows and osteoblasts catch up 2.The epiphyseal plate completely ossifies and becomes the epiphyseal line

Collagen fibers role

1.Provides flexibility and tensile strength 2.Resists stretching and twisting

Volkmann's (perforating) canals

1.Run perpendicular to the central canal 2.Connects the blood and nerve supply of the periosteum to the central canal

Central canal

1.Runs through the core of an osteon2.Carries blood vessels and nerves

skull

22 total bones, cranium and facial bones

Cranium

8 bones, encloses the cranial cavity

Muscle fiber

= muscle cell

Colles fracture

A break at the distal portion of the radius

lever

A lever is a rigid structure that moves on a fixed point called the fulcrum. 1. They allow movement of a heavier load or to move a load further and faster. 2. Consists of a bar that moves on a fixed point called a fulcrum 3. Bones act as levers; joints as fulcrums

Blood supply to bone:

A. Nutrient Artery & Vein: penetrates the shaft B. Metaphyseal Vessels: diaphyseal surface of epiphyseal cartilage C. Epiphyseal Vessels: fill the numerous foramina D. Periosteal Vessels: supply blood to superficial osteons of the shaft

Compression fractures

Bones "jam" together

Spiral fractures

Bones twist along the length of the bone

Lamellae

Concentric rings surrounding the central canal that form the osteon

Appendicular Skeleton

Consists of: -Upper and lower limbs -Pectoral and pelvic girdles which attach the limbs to the axial skeleton

Seven bones that make up orbital complex:

FMLESPZ (frontal, maxilla, lacrimal, ethmoid, sphenoid, palentine, zygomatic)

Epiphyseal fractures

Fractures within the epiphyseal region

Hormonal control of bone growth (2)

Growth hormone & Estrogen and testosterone

Controls of remodeling:

Hormonal control & Mechanical stress

Bone is composed of (3)?

Hydroxyapitite Collagen fibers Bone cells

Bone growth that occurs post natal:

Interstitial growth, Closure of the epiphyseal plate, Hormonal control of bone growth, Appositional growth

Skull bones of face (14)

Nasal (2) Inferior nasal concha (2) zygomatic bones (2) lacrimal bones (2) palantine bones (2) vomer maxillary (2) mandible

Pott fracture

Occurs at the ankles and affects both the tibia and the fibula

Greenstick fractures

Only one edge of the bone breaks while the other edge bends

Trace the route of nutrients from the periosteum to an osteocyte:

Periosteum, Perforating Canals, Central Canals, Canaliculi, Lancunae, Osteocytes

Fixator

Reduces undesirable or unnecessary movement

Three types of muscle tissue

Skeletal◦Cardiac◦Smooth Differ in function, structure, and location

Remember carpal bones

Some Lovers Try Positions That They Can't Handle a. Proximal row 1. Scaphoid 2. Lunate 3. Triquetral 4. Pisiform b. Distal row 1. Trapezium 2. Trapezoid 3. Capitate 4. Hamate

5 function of bones

Support (body) Protection (soft organs) Movement (muscles attach & pull on bone) Mineral Storage (calcium, phosphate, & fat) Hemopoiesis (blood cell formation)

Comminuted fractures

The fractured area shatters into many bony fragments

why is the foramen lacerum only seen in a complete skull?

The hole is covered by cartilage (connective tissue) in the postnatal period found on each side of the skull base, at a close distance from the pharyngeal tubercle of the occipital bone

Functional characteristics of muscle tissue

a. Excitability - respond to stimulus b. Contractility - shorten when stimulated c. Elasticity- can recoil/rebound to original resting length after contraction or stretching d. Extensibility - can stretch beyond resting length when relaxed and still be primed to contract

Differences between female and male pelvis

a. Females have a larger inlet and outlet than males b. Females pubic angle is greater than 90o , males is less than 90o c. Female ischial spines point more posteriorly d. Female coccyx tends to point downward, males coccyx curves anteriorly e. Females iliacs flare wider and are shallower than males, while males are narrower and deeper

Factors influencing joint stability

a. Fit of articulating surfaces- the better the fit the more stable b. Ligaments i.Number of ligaments- increase number of ligaments = increased stability ii.Tension of ligaments- the tighter the ligaments, the more stable c. Muscle tone- increased muscle tone will increase tension of the tendons crossing the joint

Estrogen and testosterone

a. Induces growth spurts during puberty b. Responsible for the closure of epiphyseal plates later on c. Plays a role in maintaining bone density

Endosteum

a. Membrane lining the medullary cavity, the trabeculae of spongy bone, and central canals Inner surface of bone Consists of osteoprogenitor cells Actively involved in repair and growth

Functions of the Muscular System

a. Movement - muscles attach directly or indirectly to bone, pull on bone or tissue when they contract b. Maintain posture/ body position - muscles are continuously contracting to make adjustments to maintain posture c. Stabilizes joints - tendons crossing joints and muscle tone d. Thermogenesis - generate heat when contracting

Periosteum

a. Outside membrane covering the diaphysis b. Richly supplied with blood vessels Isolates and protects the bone from surrounding tissue Provides a route for circulatory and nervous supply Actively participates in bone growth and repair Attaches the bone to the deep fascia

seven bone shapes:

a.Long b.Short c.Sesamoid d.Flat e.Irregular f.Sutural g.Pneumatized

Muscle Types

a.Skeletal - Movement, posture, generate heat b.Cardiac - Move blood through body c.Smooth - Involuntary actions, e.g., maintain blood pressure, propel substances through organs, various other functions

Osteoclasts

bone-destroying cells Break down bone matrix for remodeling and release of calcium ◦Multinucleated cells ◦Secrete acids, which dissolve the bones thereby causing the release of stored calcium ions and phosphate ions into the blood ◦This process is called osteolysis.

Hydroxyapitite role

calcium phosphate salts 1.Gives bone its hardness 2.Ability to resist compression

Lacuna

cavities containing osteocytes

vertebral column

cervical (7) thoracic (12) lumbar (5) sacrum (1) coccyx (1)

Axial Skeleton

consists of the skull, hyoid, vertebral column, ribs, and sternum

sutures of the skull

coronal sagittal lambdoid squamous

What bones articulates with the occipital condyles

first vertebrae, atlas

Skull bones of cranium (8)

frontal parietal (2) temporal (2) occipital sphenoid ethmoid

First class lever- rare

fulcrum is between applied force and the resistance. (change direction of force). See-saw. 1.effort - fulcrum - load 2. mechanical advantage or disadvantage depending on which the fulcrum is closer to 3. Example: lifting your head a. Load - face and cranial bones b. Fulcrum - alanto-occipital joint c. Effort - posterior neck muscles

Interstitial growth

growth in length 1.Chondrocytes on epiphyseal side divide 2.Older chondrocytes closer to the diaphysis calcify and die 3.Osteoclasts breakdown calcified matrix 4.Osteoblasts deposit new bone from the diaphysis side

Five Regions of vertebral column:

i. Cervical - 7 vertebrae (C1 - C7) ii. Thoracic - 12 vertebrae (T1 - T12)- articulate with ribs iii. Lumbar - 5 vertebrae (L1-L5) iv. Sacrum - 5 fused vertebrae (S1- S5), posterior portion of the pelvis v. Coccyx - 4 partially fused vertebrae

Fascicle arrangement

i. Circular- fascicles are arranged in concentric rings, surround body openings Closed when contracted, open when relaxed ii. Convergent - broad origin, fascicles converge to a single tendon Permits a variety of movements and strength iii.Parallel fascicles - arranged along the long axis of the muscle Maximum shortening but not very strong; Strap like or fusiform iv.Pennate- short fibers running at an angle converge into a central tendon, feather-like Strongest but little movement Unipennate Bipennate Multipennate

Skeleton muscle

i. Multiple peripheral nuclei ii. Striated iii. Alternating pattern of light (I=isotropic) and dark (A=anisotropic) bands iv. Longest muscle cells v. Voluntary rapid contractions but tire easily vi. Extremely adaptable

Cardiac muscle

i. One (typical) or two central nuclei ii. Striated like skeletal muscle, but branched iii. Intercalated discsi v. Found only in the heart v. Involuntary contracts at a fairly steady rate set by the heart's pacemaker

Smooth muscle

i. One central nucleus ii. Nonstriated iii. Involuntary iv. Fusiform shape (spindle) v. Lines the walls of hollow visceral organs vi. Forces fluid and other substances through internal body channels vii. Slow and sustained involuntary contractions

Neuromuscular junction

i.Axon terminal ii.Synaptic cleft iii.Motor end plate

Muscle-tendon junction

i.Muscle: Skeletal ii.Tendon: Fibrous (dense regular) CT

The three functional classes of:

i.Synarthrosis- immovable ii.Amphiarthrosis- slightly movable iii.Diarthrosis- freely movable

Osteoblasts

immature/bone-forming cells, found on the inner and outer surfaces of bone ◦Produce osteoid, which later becomes mineralized ◦Osteoblasts are involved in making new bone in a process called osteogenesis

lumbar vertebra

large, thick, oval body small, triangular vertebral foramen

C7

long spinous process that is not bifid (split in two)

Muscles of mastification:

masseter temporalis

what does the sella turcica protect and what cranial nerve is near it?

pituitary gland & optic nerve

Normal Curvatures of the vertebral column

primary and secondary

Bone Ossification

replacing other tissue with bone

Second class lever - uncommon

resistance is between the applied force and the fulcrum. (force). Wheelbarrow. 1. fulcrum - load - effort 2. always mechanical advantage 3. Example: up on your toes A. Fulcrum - joints in the foot B. Load - body weight C. Effort - soleus and gastrocnemius inserting on calcaneus

Diaphysis

shaft of the bone1.Composed of compact bone

Muscle Nomenclature

shape, location of attachment, direction of fibers, number of origins, size, location, action

Axial skeleton consists of:

skull sternum ribs vertebral column

Rib #1

smallest rib w/ greatest curvature, flattened with grooves on superior surface for subclavian vessels

Most skeletal muscles

span joints and are attached to bone in at least two places

what passes through the vertebral canal?

spinal cord

what passes through the intervertebral foramen?

spinal nerve roots, artery, veins, ligaments

Two types of bone:

spongy and compact

Osteoprogenitor cells

stem cells that create osteoblasts ◦Found on the innermost layer of the periosteum and the inner lining of the endosteum ◦Differentiate to form new osteoblasts ◦Heavily involved in the repair of bones after a break

Osteon (Haversian System)

the structural unit of compact bone Elongated cylinder surrounding a central canal

Mechanical pulleys

used to change the direction of a force in order to accomplish a task more easily and efficiently. ex Quadriceps & patella

thoracic vertebra

vertebral body=heart shaped & extra facets

Which bones make up the bony nasal septum?

vomer & perpendicular plate of ethmoid

Smooth

◦Involuntary actions◦ Maintain blood pressure ◦Propels substance through organs ◦Various other functions

Cardiac

◦Move blood through body

Skeletal

◦Movement -pull on bone or tissue when contracting ◦Posture/body position -continual contractions (tone) ◦Generate heat

The skeletal system is made of:

◦Skeletal bones ◦Cartilage ◦Ligaments ◦Connective tissue to stabilize the skeleton

Osteocytes

◦mature bone cells that maintain the matrix ◦Cause the release of calcium ions from the bone to the blood ◦Sit in depressions called lacunae