Musculoskeletal system

Question 1

cartilages

Answer 1

is a semi-rigid connective tissue that is found all throughout the body. While cartilage is not as strong as bone, it is much more resilient and flexible.

Question 2

Chondroblasts,

Answer 2

which are the mature cells that produce the matrix of cartilage.

Question 3

Chondrocytes

Answer 3

which are the cells encased within the matrix. These cells live in small spaces within the matrix, called lacunae.

Question 4

skeletal system

Answer 4

consists of the bones, articulations (joints), cartilage, as well as other connective tissues that help to strengthen and stabilize the bones and articulations.

Question 5

Cartilage has 3 main functions in the body:

Answer 5

1. provides support to the soft tissue
2. Provides a protective covering at articulating surfaces.
3. Serve as a model for bone growth

Question 6

There are 3 types [text annotation indicator] of cartilage found in the body:

Answer 6

1. hyaline cartilage
2. fibro-cartilage
3. Elastic Cartilage

Question 7

Hyaline Cartilage

Answer 7

most common and weakest form in the body
Provides support through resiliency & flexibility
Functions to help support soft tissue, form the fetal skeleton, and serves as a model for most future bone growth
Location: articulations (joints), nose, trachea, larynx, costal cartilage (where the ribs attach to the sternum)

Question 8

Fibrocartilage

Answer 8

Extremely durable
Functions to act as a shock absorber & help the body resist compressive forces
Location: intervertebral discs, pubic symphysis, menisci

Question 9

Elastic Cartilage

Answer 9

Contains numerous elastic fibers within its matrix, ensuring resiliency & flexibility
Location: epiglottis (structure in the throat), external ear

Question 10

Function of the Bone

Answer 10

Support & Protection - Bones serve as a framework of support for the entire body.
Movement - Bones serve as the attachment site for muscles, soft tissue, and some organs.
Hemopoiesis - The process of producing new blood cells is called hemopoiesis
Storage - Approximately 90% of the calcium and phosphate in the body is stored and released by the bones.

Question 11

long bone

Answer 11

Bones that have a greater length than width
Have a long, cylindrical shaft
Most common
Predominantly found in the upper & lower limbs (femur, humerus, tibia, ulna,

Question 12

short bone

Answer 12

Bones that have nearly equal length and width.
External surface covers = compact bone; internal = spony bone
Found in the wrist (carpals) and foot (tarsals)

Question 13

flat bone

Answer 13

Bones that have a flat, think surface.
Provide lots of surface area for muscle & soft tissue attachment
Found in many bones that form the roof of the skull, scapula (shoulder blades), and ribs

Question 14

irregular bone

Answer 14

Bones with elaborate, complex shapes that don’t fit any of the other classes.
Examples include the vertebra, os coxae (hip bones), and some bones in the skull

Question 15

Sesamoid Bones

Answer 15

Bones that embedded within a tendon

Found in the knee (patella) and on the bottom side of the foot

Question 16

diaphysis

Answer 16

of a long bone is its long, cylindrical shaft. The diaphysis plays an important role in help provide leverage and structural support.

Question 17

The diaphysis of the bone contains the following structures

Answer 17

Medullary Cavity
Endosteum
Periosteum

Question 18

Epiphysis

Answer 18

of a long bone are its expanded, knobby regions located on the ends of the bone. The epiphysis helps to strengthen to joint by increasing the surface area for bone-to-bone contact and functions as an attachment site for many tendons and ligaments.

Question 19

Metaphysis

Answer 19

of a long bone is the region of the bone that lies between the diaphysis and epiphysis. In a growing bone, this is the region of the bone that contains the epiphyseal plates, or growth plates.

Question 20

Osteoprogenitors

Answer 20

Stem cells found within the endosteum and periosteum. These cells help produce more stem cells that later mature to become osteoblasts.

Question 21

Osteoblasts

Answer 21

: Cells that produce new bone.

Question 22

Osteocytes

Answer 22

Mature bone cells that reside within the lacunae (small spaces within the matrix). These cells help maintain the bone matrix by detecting any sort of mechanical stress on a bone.

Question 23

Osteoclasts

Answer 23

These are large, multinucleate, phagocytic cells are involved with a process known as bone resorption (dissolves bone).

Question 24

a long bone contains 4 major sets of blood vessels:

Answer 24

Nutrient blood vessels The nutrient artery and vein are responsible for supplying the diaphysis of the bone.
Metaphyseal blood vessels The metaphyseal arteries and veins are responsible for supplying blood between the diaphysis and epiphysis.
Eiphyseal blood vessels: The epiphyseal arteries and veins are responsible for supplying blood to the epiphysis and epiphyseal plate.
Periosteal blood vessels The periosteal arteries and veins are responsible for supplying blood to the periosteum of the bone.

Question 25

During aging, our bones change in two ways:

Answer 25

1. We lose the ability to produce organic matrix due to a reduction in the osteoctye activity. This, in turn, results in a failure of the osteoblasts to produce enough new bone growth to maintain the matrix. (a.k.a osteocytes stop telling osteoblasts to build bone) 2. We lose calcium and other bone salts.

Question 26

osteoporosis

Answer 26

The changes in bone that occur during aging can result in a decrease in an individual's bone density

Question 27

how many bones does the adult body have

Answer 27

206

Question 28

axial skeleton

Answer 28

forms the main framework that supports and protects the organs. A total of 80 bones form the axial skeleton, including the skull, vertebral column, and thoracic cage.

Question 29

appendicular skeleton

Answer 29

is made up of 126 bones (63 per side) and includes the bones of the upper and lower limbs, along with the girdles that help attach the upper and lower limbs to the axial skeleton.

Question 30

articulation

Answer 30

or joint, is the location of contact between: 1) bones, 2) bones and cartilage, or 3) bones and teeth. Articulations can vary in both stability and mobility, depending on the structure of the joint.

Question 31

Synarthroses

Answer 31

Immobile joint Most stable Example: sutures of the skull

Question 32

Amphiarthroses

Answer 32

Slightly mobile join | Examples: intervertebral, tibiofibular

Question 33

Diarthroses

Answer 33

Freely mobile joint | Examples: knee, elbow, shoulder, hip, many more...

Question 34

Fibrous joints

Answer 34

use dense regular connective tissue to hold bones together. Most fibrous joints are immobile or only slightly mobile.

Question 35

3 type of Fibrous Joints

Answer 35

Gomphoses Suture syndesmoses

Question 36

Gomphoses

Answer 36

are only found where the roots of the teeth articulate with the sockets in the maxilla and mandible. Think "peg in a socket" The teeth are held together by a fibrous peridontal membrane

Question 37

Sutures

Answer 37

are immobile fibrous joints found between some bones of the skull Contain distinct, interlocking, usually irregular edges that help increase strength and decrease fractures Permit the skull to grow as the brain increases in size during childhood Sutures completely fuse together in adulthood

Question 38

Syndesmoses

Answer 38

are fibrous joints found between parallel long bones (radius & ulna, tibia & fibula). Allow for slight movement (amphiarthroses) Shafts of the parallel bones are bound side-by-side by a broad, ligamentous sheet called an interosseous membrane, which provides a pivot point where the bones can move against one another.

Question 39

Medullary Cavity

Answer 39

The hollow, cylindrical space within the diaphysis.

Question 40

Endosteum

Answer 40

A thin layer of cells that lines the inner surface of the medullary cavity. It covers most internal surfaces of the bone and contains osteoblasts and osteoclasts

Question 41

Periosteum

Answer 41

Long bones are surrounded in a tough, sleeve-like layer of dense, fibrous connective tissue. Periosteum covers all external surfaces of the bone, except the areas that are covered by articular cartilage

Question 42

Cartilagenous joints

Answer 42

use cartilage to attach bones together. Like fibrous joints, cartilaginous joints lack a joint cavity

Question 43

2 types of cartilgenous joints

Answer 43

synchondroses | symphyses

Question 44

Synchondroses

Answer 44

are cartilaginous joints held together by hyaline cartilage. Immobile joints (synarthroses) Found in the epiphyseal plates of children (helps bind the epiphysis & diaphysis of long bones) Also located in the costochondral joints (between the ribs and the costal cartilage)

Question 45

Symphyses

Answer 45

are cartilaginous joints held together by a pad of fibrocartilage. All permit slight movement (amphiarthroses) Shock absorber for joints - help resist compression Pubic symphysis, located between the right and left pubic bones Intervertebral joints, located between the bodies of the vertebrae

Question 46

Synovial joints

Answer 46

are separated by a space, referred to as the joint cavity. (shoulder, elbow, knee, ankle, wrist,

Question 47

Tendons

Answer 47

attach muscle to bone

Question 48

joint cavity

Answer 48

that contains snyovial fluid, helping to separate the articulating bones

Question 49

Synovial fluid

Answer 49

which is secreted by the inner layer of the articular capsule (synovial membrane) Lubricates the articular cartilage Noureshes the articular cartilage Acts as a shock absorber

Question 50

Bursa

Answer 50

Fibrous sac-like structure that contains synovial fluid | Designed to eleviate friction from various body movements

Question 51

Fat pads

Answer 51

are the "packing material" of the joint, serving to providing protection

Question 52

Sensory nerves and blood vessels

Answer 52

innervate and supply blood to the articular capsule and associated ligaments Nerves signal pain, amount of motion, & stretch in the joint Vessels nourish the tissues within the joint

Question 53

Uniaxial

Answer 53

bone moves in only one plane or axis

Question 54

Biaxial

Answer 54

bone moves in two planes or axis

Question 55

Multiaxial

Answer 55

bone moves in more than two planes or axis

Question 56

Plane (gliding) joint:

Answer 56

``` Simplest synovial articulation Least mobile Uniaxial Flat, or planar, articulating surfaces Examples: intercarpal, intertarsal ```

Question 57

Hinge joint:

Answer 57

Uniaxial Convext surface of one bone articulates with concave depression of another bone Think "hinge on a door" Examples: tibiofemoral, interphalangeal

Question 58

Pivot joint:

Answer 58

Uniaxial Rounded surface on one bone articulates with a ring formed by a ligament and another bone Bone rotates around a longitudinal axis Examples: radioulnar, atlantoaxial

Question 59

Condylar (ellipsoid) joint:

Answer 59

Biaxial Oval, convex surface on one bone articulates with a concave articular surface on another Examples: metacarpophalangeal, radiocarpal

Question 60

Saddle joint:

Answer 60

Biaxial, but allows for greater movement than a condylar joint Articular surfaces have convex and concave regions Resembles the shape of a saddle Examples: I carpometacarpal

Question 61

Ball-and-socket joint

Answer 61

Multiaxial Most freely mobile synovial joint Spherical articulating surface of one bone articulates with a rounded, cup-like socket on another bone Examples: glenohumeral, iliofemoral

Question 62

Excitability

Answer 62

Level of responsiveness Outside stimuli have the ability to initiate electrical changes within the muscle fiber (cell), leading to contraction of the muscle fiber

Question 63

Contractility

Answer 63

When a muscle fiber is stimulated, it generates tension (contraction) within the cell that can lead to shortening of the muscle fiber Shortening then pulls on bones, resulting in movement

Question 64

Elasticity

Answer 64

Cell's ability to return to its original length | Contracted muscle cells will recoil back to their resting lengthen once the applied tension is removed

Question 65

Extensibility

Answer 65

Capable of extending in length, in response to the contraction of opposing muscles Example: when the biceps contract to flex the elbow, the triceps must stretch

Question 66

Cardiac muscle fibers are found almost exclusively within the heart wall. These fibers posses the following characteristics:

Answer 66

Striated Posses only 1 or 2 nuclei Form Y shaped branches Join adjacent muscle fibers to form junctions called intercalated discs Contraction results in movement of blood Under involuntary control

Question 67

authorhythmic

Answer 67

Cardiac muscle tissues are capable of generating an impulse without the nervous system.

Question 68

Smooth muscle fibers are found within the walls of the viscera (organs of the abdominopelvic cavity). These fibers posses the following characteristics:

Answer 68

No striations Posses a single, centrally located nucleus Relatively short, spindle-shaped cells (wide in the middle, tapered on ends) Contraction results in movement of food and blood Under involuntary control

Question 69

Body Movement

Answer 69

Skeletal muscles attach to bone through tendons | Skeletal muscle contracts, causing tendons to pull on bones, resulting in movement

Question 70

Maintenance of Posture

Answer 70

Contraction of some skeletal muscles helps to stabilize joints & maintain posture Postural muscles are continuously contracting (when awake) to maintain upright postion

Question 71

Temperature Regulation

Answer 71

Muscle contraction requires energy & head is a byproduct of energy Helps maintain our normal body temperature Think about exercise - when you work out, you physically feel warmer! Think about when you're cold! Your muscles contract & relax (shivering) in an attempt to produce heat

Question 72

Storage & Movement of Materials

Answer 72

Sphincters (circular muscles) contract at body openings to control the flow and passage of materails

Question 73

Support

Answer 73

Skeletal muscles can be aligned in flat sheets/layers Sheets help protect organs & support their weight Think about your abdominal muscles that help hold the abdominal organs in place

Question 74

Skeletal muscles are made up of numerous skeletal muscle fibers. As such, we organize skeletal muscles as follows from superficial to deep:

Answer 74

Each muscle is comprised of multiple fascicles Muscle fibers are organized into bundles, called fasciles Muscle fibers contain myofibrils Myofibrils are made up of myofilaments Myofilaments are mainly composed of actin and myosin

Question 75

endomysium

Answer 75

is the innermost layer that surrounds and electrically insulates each muscle fiber

Question 76

perimysium

Answer 76

is the middle layer that surrounds each of the fasciles.

Question 77

epimysium

Answer 77

is the most superficial layer that surrounding the entire skeletal muscle

Question 78

deep fascia

Answer 78

helps to separate individual muscles, bind together muscles with common functions, and forms sheaths to help distribute blood vessels and nerves to the tissues.

Question 79

superficial fascia

Answer 79

is located external to the deep fascia and helps to separate the muscle from the skin.

Question 80

At the ends of each muscle, all of the connective tissue merge together to form a

Answer 80

tendon

Question 81

The less mobile attachment of the muscle is termed the

Answer 81

origin.

Question 82

The more mobile attachment of the muscle is termed the

Answer 82

insertion

Question 83

Isometric Contractions

Answer 83

Length: does not change Speed: does not change Resistance: can change Results in NO movement Tension produced by the muscle does not exceed the resistance (load) Example: trying to lift an extremely heavy object, pushing against a wall

Question 84

Isotonic Contractions

Answer 84

``` Length: changes Speed: changes Resistance: remains the same Results in MOVEMENT Tension produced by the muscle is equal or greater than the resistance (load) Example: bicep curl, squats 2 types of isotonic contractions: ``` A contraction is said to be concentric when the muscle actively shortens. A contraction is said to be eccentric when the muscle lengthens

Question 85

Circular Muscles

Answer 85

Fibers are concentrically aligned around an opening or recess Circular muscles are also called sphincters Located at the entrances & exits of internal passageways Example: orbicularis oris (opening of the mouth)

Question 86

Parallel Muscles

Answer 86

Fascicles run parallel the long axis of the muscle Muscle shortens when contracted, and its body increases in diameter Have high endurance, but not as strong as other types of muscles Example: rectus abdominis (forms the "six-pack")

Question 87

Convergent Muscles

Answer 87

Widespread muscle fibers that converge into a common attachment site Often triangular in shape & resemble a broad fan Versatile muscle - direction of pull can change by activating a single group of fibers Example: pectoralis major (chest muscle)

Question 88

Pennate Muscles

Answer 88

Tendons and muscle fibers resemble a large feather | One or more tendons extending through their body, with fasciles arranged at an oblique angle to the tendon

Question 89

3 types of Pennate Muscles

Answer 89

Bipennate Unipennate Multipennate

Question 90

All muscle fibers on the same side of the tendon | Example: extensor digitorum (extends the fingers)

Answer 90

Unipennate

Question 91

Muscle fibers on both sides of the tendon | Example: rectus femoris

Answer 91

Bipennate

Question 92

Branches of tendon within the muscle | Example: deltoid

Answer 92

Multipennate

Question 93

is the wasting away of tissue that results in a reduction of muscle size, tone, and power.

Answer 93

Muscle atrophy

Question 94

is an increase in the size of muscle fibers

Answer 94

Muscle hypertrophy

Question 95

Agonist

Answer 95

a.k.a prime mover Contraction produces a specific movement Example: triceps brachii (posterior arm) is agonist in extension of the elbow

Question 96

Antagonist

Answer 96

Muscle whose action opposes the agonist If agonist produces extension, antagonish will produce flexion (and visa versa) Example: biceps brachii would be an antagonist to the triceps brachii

Question 97

Synergist

Answer 97

Muscle who assists the action of the agonist Typically more useful at the start of movements Example: biceps brachii and brachialis muscles of the arm are synergists, both working together to flex the elbow

Question 98

Muscle Action

Answer 98

Name indicates the primary function or movement of the muscle i.e. flexor, extensor, pronator Examples: flexor digitorum longus, pronator quadratus, etc.

Question 99

Specific body regions

Answer 99

Name indicates the region of the body where the muscle is located i.e. superficialis, externus, anterior, profundus Examples: tibialis anterior, flexor digitorum profundus, rectus femoris

Question 100

Muscle attachments

Answer 100

Name indicates the muscle's origins, insertions, or other prominent attachment points Examples: sternocleidomastoid, intercostals, subscapularis

Question 101

Orientation of muscle fibers

Answer 101

Name indicates the direction or orientation in which the muscle fibers align i.e. rectus, oblique, orbicularis Examples: rectus abdominis, external oblique

Question 102

Muscle shape and size

Answer 102

Name indicates the general shape or size of a muscle i.e. magnus, teres, deltoid, trapezius, longus, magnus, etc. Examples: gluteus minimus, adductor longus, pectoralis minor, etc.

Question 103

Muscle heads/tendons of origin

Answer 103

Name indicates specific features like how many tendons of origin, the number of muscle bellies, or number of heads the muscle contains i.e. bi, tri, quad, etc. Examples: biceps brachii, quadriceps femoris, triceps brachii