A & P 1 Lecture units Comb 6 & 7

Classification of Skeletal Muscle Contractions

Isotonic contraction - muscle changes length but tension doesn't change. Concentric isotonic contraction - shortening a muscles but maintaining constant tension such as in lifting a glass from a table. Eccentric isotonic contraction - muscle lengthening occurs with constant tension such as lowering a glass back onto the table. Isometric contraction contraction - muscle does not change in length and tension doesn't change either. No movement occurs with this type of contraction and is used for bearing loads such as lifting a heavy object up in the air.

The insertion of the biceps is the scapula. 1. true 2. false

2. false

we have a great range of motion in our pectoral girdle because it is tightly attached to the body frame 1. true 2. false

2. false

Which muscle below becomes tendinous at back of ankle and travels to sole of foot where it divides into four tendons and can flex the four lateral toes? 1. popliteus 2. flexor digitorum longus 3. flexor halluncis longus 4. gastrocnemius 5. soleus

2. flexor digitorum longus

Which one of the following terms best describes the dense layer of connective tissue that surrounds the cartilage of a developing bone? 1. diaphysis 2. perichondrium 3. osteoid 4. endosperm

2. perichondrium

All of each I band is contained within a sarcomere. 1. true 2. false

2. false

The diploe of flat bones is typified by the presence of a diaphysis, epiphysis and medullary cavity. 1. true 2. false

2. false

The oxygen debt of a muscle in prolonged state of contraction is the time it takes to replace all the creatine phosphate reserves. 1. true 2. false

2. false

The primary and secondary curves of the vertebral column are present from birth 1. true 2. false

2. false

The sarcoplasmic reticulum is a type of rough Endoplasmic Reticulum which releases Calcium ions during contraction of the muscle fiber. 1. true 2. false

2. false

The ulna primarily articulates with only the humerus and the carpal bones of the wrist 1. true 2. false

2. false

Ribs 11 and 12 do not attach to the sternum and are called what? 1. true ribs 2. floating ribs 3. false ribs

2. floating ribs

what structure of the femur at its most proximal end can be palpated on the side of the hip? 1. medial condyle 2. greater trochanter 3. lateral epicondyle 4. lesser trochanter 5. lateral condyle

2. greater trochanter

If both the right and left sternocleidomastoid muscles contract together, what action results? 1. head moves to right 2. head moves down toward the ground 3. head moves up toward the ceiling 4. head moves to left

2. head moves down toward the ground

Which bone is horseshoe-shaped and located just superior to the larynx? 1. nasal 2. hyoid 3. palatine 4. lacrimal 5. zygomatic 6. mandible 7. maxilla

2. hyoid

what anterior edge on the hip can be palpated and is the site of attachment for abdominal muscles? 1. obturator foramen 2. iliac crest 3. acetabulum 4. ischial tuberosity 5. anterior superior iliac crest

2. iliac crest

Which of the following muscles are flexors of the hip? 1. tensor fascia lata, psoas 2. iliacus, psoas 3. gluteus medius, iliacus 4. gluteus maximus, gluteus medius

2. iliacus, psoas

Which vertebral type has the largest body? 1. lumbar 2. cervical 3. sacral 4. coccygeal 5. thoracic

1. lumbar

which carpal bones articulate with the radius and ulna? 1. pisiform, lunate and triquetral 2. scaphoid, lunate and triquetral 3. trapezium, trapezoid, capitate 4. hamate, trapezoid, capitate

2. scaphoid, lunate and triquetral

The superior radioulnar joint is an example of which one of the following types of joint? 1. ball-and-socker 2. saddle 3. gliding (plane) 4. pivot 5. condyloid (ellipsoid)

4. pivot

The orbicularis oculi has which one of the following actions? 1. closes the eye 2. opens the eye 3. rotates the eye 4. elevates the eye 5. protrudes the eye

1. closes the eye

From a functional point of view, what type of joint allows free movement such as the knee or shoulder joint? 1. diarthroses 2. amphiarthroses 3. synarthroses

1. diarthroses

Starting from the point at which ATP binds to the heads of the myosin filaments, place the following in the correct sequence to describe the muscle contraction cycle 1. crossbridge formation, ATP hydrolysis, crossbridge detachment, power stroke 2. crossbridge formation, power stroke, crossbridge detachment, ATP hydrolysis 3. crossbridge detachment, ATP hydrolysis, crossbridge formation, power stroke 4. ATP hydrolysis, crossbridge formation, power stroke, crossbridge detachment

4. ATP hydrolysis, crossbridge formation, power stroke, crossbridge detachment

What is the origin of the zygomaticus minor muscle? 1. modiolus 2. lesser wing of sphenoid 3. superior tarsus (eyelid) 4. zygomatic bone

4. zygomatic bone

ATP Formation and Levels of Exercise

Resting muscle cell has only a small amount of ATP ready for use in contraction. Creatinephosphate which is present in the muscle cells passes phosphate quickly to ADP to make more ATP during the initial phases of strenuous muscle contraction. After a while, aerobic respiration of glucose from glycogen (stored in muscle) generates needed ATP for 5 to 10 minutes. For the next half hour, glucose and fatty acids delivered from bloodstream provide a source of energy for ATP production. If strenuous muscle contraction continues and oxygen runs out, then glycolysis will begin and accumulate ATP and lactic acid until muscle contraction ceases due to cramping. Then oxygen debt is paid by rapid breathing to take in more oxygen quickly.

The insertion of a muscle is that end which during contraction, stays relatively motionless. 1. true 2. false

2. false

Which muscle below is the longest muscle in the body and travels obliquely across the front of the thigh? 1. vastus medialis 2. sartorius 3. rectus femoris 4. vastus lateralis 5. vastus intermedius

2. sartorius

Which of the muscles below insert on the lesser trochanter of the femur? 1. gluteus medius 2. gluteus minimus 3. gluteus maximus 4. none of these muscles

4. none of these muscles

A straight muscle fits into which one of the following categories? 1. convergent 2. fusiform 3. pennate 4. parallel 5. orbicular

4. parallel

What anatomic feature is represented and able to be palpated in the region of the medial or inner portion of one's ankle? 1. medial malleolus 2. medial condyle 3. anterior border 4. tibial tuberosity 5. lateral condyle

1. medial malleolus

Which artery is responsible for bringing nutrients and oxygen to the inner part of compact bone, spongy bone and bone marrow? 1. nutrient artery 2. epiphyseal artery 3. metaphysical artery

1. nutrient artery

Which small square muscle below lies on the anterior distal forearm with its origin on the ulna, insertion on the radius and action to pronate the forearm. 1. pronator quadratus 2. extensor digitorum 3. anconeus 4. flexor pollicis longus 5. brachioradialis

1. pronator quadratus

Choose the correct class of lever to describe when the load is placed between the fulcrum and the effort (force) as in raising your heel from the ground 1. second class lever 2. third class lever 3. fourth class level 4. first class lever

1. second class lever

Which one of the following terms best describes the role of brachialis, given that it assists biceps brachii in flexing the elbow? 1. synergist 2. prime mover 3. antagonist 4. agonist 5. fixator

1. synergist

In muscle contraction, when calcium is released from the cellular storage system, the myosin head forms a ""cross-bridge"" between the myosin and the actin filament. 1. true 2. false

1. true

Many muscles operate together to produce the same movement and are termed ""synergists". 1. true 2. false

1. true

Muscle tension is the collective force formed during contraction. 1. true 2. false

1. true

Rigor mortis is caused by the lack of ATP. 1. true 2. false

1. true

The platysma is the antagonist of the zygomatic minor muscle. 1. true 2 false

1. true

The proximal end of ulna forms the elbow. 1. true 2. false

1. true

The sarcomere is considered to be the contractile unit of the muscle. 1. true 2. false

1. true

The tibia of the lower leg forms the "shin bone". 1. true 2. false

1. true

The zygomatic minor muscle is the antagonist of the platysma. 1. true 2. false

1. true

the cervical curve of the vertebral column forms when the baby is able to hold its head up 1. true 2. false

1. true

What is the action of the deltoid muscle? 1. adducts the arm 2. abducts the arm 3. laterally rotates the arm 4. medially rotates the humerus 5. flexes the arm

2. abducts the arm

Which bone listed below is not part of the viscerocranium? 1. zygomatic 2. palatine 3. temporal 4. nasal 5. lacrimal

3. temporal

Which three of the muscles below have partial insertion on the linea alba? 1. rectus abdominis, transversus abdminis, external oblique 2. diaphragm, rectus abdominis, transversus abdminis 3. transversus abdominis, internal oblique, external oblique 4. ansversus abdominis, internal oblique, rectus abdominis

3. transversus abdominis, internal oblique, external oblique

Identify the large, triangular muscle on back of the neck, shoulders and upper back that can retract the scapula and extend and laterally flex the head and neck? 1. biceps brachii 2. serratus anterior 3. trapezius 4. triceps brachii 5. pectoralis minor

3. trapezius

Which part of the temporal bone contains the external acoustic meatus and the styloid process projecting downward for attachment of ligaments and muscles? 1. mastoid process 2. petrous part 3. tympanic part 4. squamous part

3. tympanic part

What is the action for the platysma muscle? 1. raises the upper eyelid 2. closing and pursing the lips 3. wrinkles the skin of the neck 4. raises the upper lip as in smiling 5. closes eye as in winking

3. wrinkles the skin of the neck

Choose the bone listed below that is not part of the neurocranium? 1. sphenoid 2. frontal 3. zygomatic 4. ethmoid 5. occipital

3. zygomatic

What is the origin of the masseter muscle? 1. temporal bone 2. maxilla bone 3. zygomatic bone 4. mandible (coronoid process) 5. nasal bone

3. zygomatic bone

The origin of the splenius capitus includes which of the following vertebrae? 1. T8, C5 2. C7, T8 3. C5, T1 4. C7, T1 5. C1, T1

4. C7, T1

What is the origin of the teres minor muscle in the shoulder? 1. inferior angle of scapula 2. clavicle 3. infraspinous fossa of scapula 4. lateral border of scapula 5. subscapular fossa of scapula 6. supraspinous fossa of scapula

4. lateral border of scapula

What is the origin of the levator palpebrae superioris muscle? 1. superior tarsus (eyelid) 2. zygomatic bone 3. modiolus 4. lesser wing of sphenoid 5. temporal bone

4. lesser wing of sphenoid

What muscle has an action of raising the upper eyelid? 1. orbicularis oris 2. zygomatic minor 3. buccinators 4. levator palpebrae superioris 5. orbicularis oculi

4. levator palpebrae superioris

The erector spinae muscles consist of which set of three muscles listed below? 1. semispinalis, quadratus, longissimus 2. quadratus, semispinalis, iliocostalis 3. spinalis, semispinalis, iliocostalis 4. longissimus, spinalis, iliocostalis

4. longissimus, spinalis, iliocostalis

What is the origin of the orbicularis oris muscle? 1. superior tarsus (eyelid) 2. lesser wing os sphenoid 3. temporal bone 4. modiolus 5. zygomatic bone

4. modiolus

What is the origin for the occipital belly of the occipitofrontalis muscle? 1. skin of forehead 2. temporal bone 3. Galea aponeurotica 4. occipital bone 5. frontal lobe

4. occipital bone

Which thin muscle below is located on the front of the forearm with origin on the humerus, insertion on the styloid process of radius and flexes the elbow. 1. anconeus 2. pronator quadratus 3. flexor pollicis longus 4. extensor digitorum 5. brachioradialis

5. brachioradialis

Which tarsal bone forms the heel on the foot? 1. lateral cuneiform 2. talus 3. navicular 4. cuboid 5. calcaneus

5. calcaneus

When you kneel on your knee, what structure on the tibia are you kneeling on? 1. medial malleolus 2. anterior border 3. medial condyle 4. lateral condyle 5. tibial tuberosity

5. tibial tuberosity

Single unit smooth muscle is found in which one of the following? 1. male reproductive system 2. iris muscles 3. airways of the lungs 4. arrestor pili muscles 5. walls of blood vessels

5. walls of blood vessels

Which movement about a synovial joint describes bringing the fingers together? 1. abduction 2. pronation 3. protraction 4. supination 5. retraction 6. adduction

6. adduction

What is the origin of the coracobrachialis muscle in the shoulder? 1. infraspinous fossa of scapula 2. supraspinous fossa of scapula 3. subscapular fossa of scapula 4. inferior angle of scapula 5. lateral border of scapula 6. coracoid process of scapula

6. coracoid process of scapula

What is the action for the brachialis muscle? 1. extend the wrist 2. extend the elbow 3. extend the shoulder 4. flex the wrist 5. flex the shoulder 6. flex the elbow

6. flex the elbow

What is the insertion for the semispinalis capitis muscle? 1. spinous processes of T3 - T6 vertebra 2. C1 - C3 transverse processes 3. clavicle 4. scapula 5. transverse processes of T3 - T6 vertebra

2. C1 - C3 transverse processes

what feature distinguishes thoracic vertebra from other types? 1. absence of articulating facets on transverse processes 2. presence of articulating facets on transverse processes 3. largest body of all vertebral types 4. presence of transverse foramen on transverse process

2. presence of articulating facets on transverse processes

Which one of the following pairs of ribs is considered to be false? 1. 1st 2. 6th 3. 3rd 4. 9th

4. 9th

What is the origin of the teres major muscle in the shoulder? 1. infraspinous fossa of scapula 2. clavicle 3. supraspinous fossa of scapula 4. subscapular fossa of scapula 5. inferior angle of scapula 6. lateral border of scapula

5. inferior angle of scapula

which bone below contains the coronoid process at its posterior for the site of attachment of the temporals muscle on either side of the head? 1. hyoid 2. lacrimal 3. maxilla 4. nasal 5. mandible 6. zygomatic 7. palatine

5. mandible

Which one of the following terms is used for the thread-like organelles composed of actin and mysosin filaments found in muscles cells? 1. tropomysium 2. transverse tubules 3. muscle fascicles 4. muscle fiber 5. myofibrils

5. myofibrils

Mechanism of Remodeling (Shaping of Bone)

Calcium and phosphate are two key minerals needed by the body and are stored in bone. Hormones from the parathyroid gland are involved in releasing calcium from bone and also in storing it in bone. When blood calcium level is low, PTH (parathyroid hormone) is released and stimulates osteoclasts to dissolve bone, releasing calcium. When blood calcium is high, calcitonin is released and stimulates osteoblasts to make new bone.

MUSCLES OF THE FOOt

The muscles of the foot assist the flexors and extensors of the leg to move the toes and can be divided into dorsal and plantar groups.

RIBS

The twelve pairs of ribs all articulate with thoracic vertebra but only ribs 1 - 7 attach anteriorly to the sternum and these ribs are called true ribs. Ribs 8 - 10 attach by cartilage to the 7th costal cartilage and are known as false ribs. Ribs 11 and 12 do not attach to the sternum and are called floating ribs.

MUSCLES OF THE HIP

Two muscles are strong flexors of the hip and together are termed the iliopsoas which originate in the trunk and pelvis and distally, their tendons merge to form a tendon that inserts on the lesser trochanter of the femur. iliacus - large fan-shaped muscle that occupies the inside the ilium and the origin is the iliac fossaof the hip, insert on the lesser trochanter of the femur and has an action of flexing and abducting the hip and flexes the trunk. Psoas major - long thick muscle that lies on the posterior abdominal wall and forms a conjoined tendon with the iliacus. The origin is on the T1 - L5 vertebra, insertion is on the lesser trochanter of the femur and action is flexing and abducting the hip and flexes the trunk.

Muscles that act to move a limb away from the midline of the body commonly have which one of the following terms as part of their name?

abductor

When the internal intercostals and the innermost intercostals contract, what happens to the air pressure inside the thoracic cavity?

increases

which muscle below is not one of the rotator cuff muscle in the shoulder region?

deltoid

which of the following is not found in fast twitch muscle fibers?

found in large muscles like the gluteals

Which muscles form the calcaneal tendon, also known as the Achilles tendon?

gastrocnemius, soleus

what is the origin of the external intercostals?

inferior borders of ribs 1 - 11

which bone below is a single bone and forms the bridge of the nose?

nasal

a mature bone cell is called what?

osteocyte

This butterfly-shaped bone is located at the base of the cranium and contains the pituitary fossa.

sphenoid

What is the origin of the semispinalis capitis muscle?

spinous processes of T3 - T6 vertebra

which part of the temporal bone has the zygomatic process and the mandibular condyle?

squamous part

what is the origin of the subscapularis muscle in the shoulder?

subscapular fossa of scapula

Which one of the following types of fracture occurs when one bone is forcefully driven into another, affecting both ends of the bone? 1. impacted 2. green stick 3. open 4. spiral 5. compression

1. impacted

Which one of the following rotator cuff muscles serves to extend the shoulder and laterally rotate the arm? 1. infraspinatus 2. supraspinatus 3. teres minor 4. subscapularis

1. infraspinatus

Which muscle below would you use to adduct the hip and flex the knee? 1. gracilis 2. adductor brevis 3. adductor longus 4. adductor magnus

1. gracilis

Which one of the following bones is classified as a flat bone? 1. hip bone 2. tarsal 3. phalanx 4. sphenoid bone 5. patella

1. hip bone

What is the insertion of the latissimus dorsi? 1. humerus 2. clavicle 3. ulna 4. radius 5. scapula

1. humerus

"Ball and socket" joints are examples of what type of joint? 1. hyaline cartilage 2. elastic cartilage 3. fibrocartilage

1. hyaline cartilage

What is the name of the large muscle on the anterior chest wall that inserts on the humerus and can adduct and internally rotate the humerus? 1. pectoralis major 2. latissimus dorsi 3. brachialis 4. biceps brachii 5. triceps brachii

1. pectoralis major

Which two of the following muscles insert onto the humerus? 1. pectoralis major, latissimus dorsi 2. rhomboid major, pectoralis minor 3. serratus anterior. pectoralis mior 4. rhomboid major, serratus anterior

1. pectoralis major, latissimus dorsi

Which part of the temporal bone contains the internal acoustic meatus and the inner ear. 1. petrous part 2. squamous oart 3. tympanic part 4. mastoid process

1. petrous part

When you "stubb" your toe, what bony type are you bumping and hurting? 1. phalanges 2. metacarpals 3. carpal bones

1. phalanges

Which bone below forms the lower jaw. 1. hyoid 2. zygomatic 3. mandible 4. maxilla 5. nasal 6. lacrimal 7. palatine

3, mandible

Muscles that act to move a limb away from the midline of the body commonly have which one of the following terms as part of their name? 1. extensor 2. levator 3. abductor 4. adductor 5. pronator

3. abductor

MUSCLES OF THE ARM

Biceps brachii - large muscle located on front of the arm. It has two heads that merge into a single thick tendon. It has a two-fold origin with the long head attaching to the scapula and the short head attaching to the coracoid process of the scapula, insertion on the radial tuberosity of the radius and action that flexes the elbow and shoulder, abducts the arm and supinates the forearm. Triceps brachii - large muscle on back of arm which has three heads that merges into a single tendon. Origin of long head is on scapula and lateral and medial heads attach to humerus, insertion is on the olecranon of the ulna and the action is to extend the elbow and adducts the arm. Brachialis - passes in front of the elbow with origin on the humerus, insertion on the coracoidprocess of the ulna and action to flex the elbow.

Growth and Maintenance of Skeleton

Bones grow and change shape as the fetus grows and as the child grows after birth. Osteoblastsare involved in making new bone and osteoclasts are involved in bone resorption that is called bone remodeling. Note that the osteoclast does just the opposite of the osteoblast in that it resorbs bone (dissolves bone) while the osteoblast lays down new bone.

Cardiac Muscle

Cardiac muscle is similar to skeletal muscle in that it is also striated but differs in a number of ways: 1. Presence of intercalated disks (see online text) 2. Fibers are branched forming a 3-dimensional of fibers 3. Single nucleus located in the center of the fiber 4. In tissue culture, cardiac cells beat spontaneously and rhythmically 5. Cardiac muscle is involuntary Intercalated disks are junctions of two cardiac muscle cells that occur only at I Band. Desmosomes occur in intercalated disks to provide strong adhesive force, lack of calcium can cause desmosomes to break apart, separating two cardiac cells. Gap junctions are also in the intercalated disk region and provide easier connection for electrical activity to be transferred from one cardiac fiber to another by way of ion exchange. T-System in Cardiac Fibers Fine structure analysis has shown that T tubules of cardiac muscle differ from those in skeletal muscle in the following ways: 1. They are larger than those for skeletal muscle. 2. The T tubules are located at Z line rather than at the A-I junction as in skeletal muscle. 3. No large terminal cisternae are found in sarcoplasmic reticulum. 4. The protein-polysaccharide coat of muscle cell's sarcolemma is also found inside enlarged T tubules, indicating that T tubules are there to provide for larger surface area to exchange nutrient and waste products between, inside and outside of cell. It has been estimated that no point in a cardiac cell is more than 2-3 microns from the extracellular space, either at the cell surface or in one of the T tubules.

GLUTEALS

Gluteal muscles are the three large muscles forming the buttocks and responsible for extension, abduction and lateral rotation of the hip joint. Gluteus maximus - large, quadrilateral mass of muscles that forms the shape of the buttocks with origin on posterolateral ilium of the hip, insertion on the gluteal tuberosity of the femur and action to extend and abduct the hip. Gluteus medius - large muscle of outer surface of ileum with origin on lateral surface of hip, insertion on the gluteal tuberosity and action to extend and abduct the hip. Gluteus medius - large muscle of the outer surface of the ilium with origin on lateral surface of the ilium of the hip, insertion on the greater trochanter of the femur and action to extend and abduct the hip.

Bones of the hand

Hand: consists of eight cmall, irregular carpal bones in the wrist, five metacarpal bones in the palm, three phalanges in the fingers and two phalanges in the thumb. Carpal bones consist of scaphoid, lunate, triquetrum, pisiform, trapezium, trapezoid, capitate and hamate. The scaphoid and pisiform are palpable (able to be felt). The scaphoid is located in the floor what is known as the anatomical snuff box at the base of the outstretched thumb. See Anatomic snuff box for location of snuff box region and reason for calling it "snuff box". Metacarpals: five miniature long bones that support the palm of the hand. Phalanges: fourteen miniature long bones of the digits.

MUSCLES ACTING ON THE HUMERUS

Latissimus dorsi - muscle of the shoulder and shoulder girdle with origin on T7 - T12 spinousprocesses, iliac crest of hip bone and ribs 9 - 12, Insertion on humerus with action of extending, adducting and medially rotating arm at shoulder joint Pectoralis major - muscle of anterior chest wall that acts on shoulder joint with origin on medial end of scapula, sternum and costal cartilages 1 - 6, insertion on humerus and action of adducting and internally rotating the humerus, extending the should joint from a flexed position and flexes it from an extended position.

Compartments

Layers of fascia separate muscles in functionally related groups into compartments and form septa (tissue walls) between them. Found a lot in limb musculature and compartments prevent the spread of infection and helps to provide pressure around veins to help blood to return to the heart.

MUSCLES ACTING ON THE SCAPULA

Pectoralis minor - muscle on anterior chest wall that acts on the scapula with origin on ribs 3 - 5, inserts on medial border and coracoid process of scapula with an action to pull the shoulder girdle forwards and downwards. Trapezius - large, triangular muscle on back of the neck, shoulders and upper back with origin on occipital bone, nuchal ligament and C7 - T2, insertion on clavicle and scapula and action of elevating and retracting the scapula (raises or lowers shoulders) and extending and laterally flexing the head and neck. Serratus anterior- side of thorax between ribs and scapula with origin on ribs 1 - 9, insertion on costal surface of medial border of scapula and action to protract (pull forward) the scapula and pectoral girdle. Action of trapezius, pectoralis minor and serratus anterior combines in throwing motion in which shoulder movers posteriorly, then forward and down.

Length-Tension Relationship

The force with which a skeletal muscle can contract is related to the length of its sarcomeres (in experimental conditions, muscles can be stretched and the force of contraction measures). Minimal tension - when sarcomere filaments are completely understretched so few if any myosinheads are available for attachment to actin filaments. Understretched - sarcomere still understretched but a few more myosin and actin filaments are in contact with each other so some but not full contraction can take place. Maximal tension - happens when overlap zone of thin and thick filaments is ideal and happens when the overlap zone reaches from the H-band to the end of the thick filament. Overstretched - if sarcomere is overstretched, overlap between thick and thin filaments is reduced. Minimal tension - if no overlap between thick and thin filaments occurs because muscle is stretched beyond optimal range, no binding between actin and myosin filaments can occur.

Bones of the Pectoral Girdle and Arm

The pectoral girdle connects the arm via the head of the humerus to the scapula and the clavicle. Scapula: forms two articulations. Acromioclavicular joint between the acromion portion of the scapula with the acromial end of the clavicle. The glenoid fossa of the scapula articulates with the head of the humerus. Clavicle: slightly, S-shaped bone lies at base of neck and has two articulations. The acromioclavicular joint forms between the acromion of the scapula and the acromion portion of the clavicle. The sternoclavicular joint forms between the manubrium portion of the sternum and the clavicle. Humerus: articulates with the glenoid fossa of the scapula via the glenohumeral joint. Articulates with the trochlear notch of the ulna via the humeroulnar joint. Also articulates with the radial head via the humeroradial joint. Has the olecranon fossa which is a large fossa for articulation with the ulna. The medial epicondyle is a prominence that is an attachment for some muscles of the forearm but also is known as the site of the "funny bone" because the ulnar nerve runs nearby and when bumped at that site causes a tingling sensation in the forarm.

Skull

The skull is part of the axial skeleton and is made of 22 bones (most articulate via sutures). Cranial bones (neurocranium) surround and protect brain. Facial bones (viscerocranium) enclose, protect and support soft tissues of orbit, nasal and oral cavities. Eight bones are cranial bones which are the occipital bones, sphenoid bone, frontal bone, ethmoidbone, two parietal bones and two temporal bones. Fourteen bones are facial bones and they are two maxillae, two palatine bones, two zygomaticbones, two nasal bones, two lacrimal bones, the vomer, two inferior conchae and the mandible. The cranial cavity is the cavity in which the brain resides and has three large fossae - the anterior, middle and posterior cranial fossa.

MUSCLES OF THE THIGH

The thigh has four strong muscles located on the anterior surface called the quadriceps which function to extend the knee and on the back of the thigh, there is a group of muscles called the hamstrings which function to flex the knee. Anterior Compartment: Vastus lateralis - most lateral of the quadriceps with origin on the greater trochanter of the femur, insertion on the tibial tuberosity via the patella tendon and an action to extend the knee. Vastus medialis - most medial of the quadriceps with origin on linea aspera of femur, insertion on tibial tuberosity via patellar tendon and action is to extend the knee. Vastus intermedius - deepest of the quadriceps with origin on shaft of femur, insertion on tibial tuberosity via patellar tendon and action to extend the knee. Rectus femoris - most anterior of quadriceps with origin on anterior superior iliac spine and acetabulum of the hip bone, insertion on the tibial tuberosity via patellar tendon and action to extend the knee. Sartorius - longest muscle in the body, travels obliquely across front of thigh with origin on anterior superior iliac spine of hip, insertion on tibia and action to flex the hip and knee and rotate the femur. Posterior Compartment primary action of muscles in this compartment is to flex the knee joint and extend the hip. Biceps femoris - most lateral hamstring and arises from two heads with origin of long head on ischial tuberosity of hip and linea aspera of femur, insertion on head of fibula and action to flex the knee and extends the hip. Semitendinosus - the most middle hamstring and becomes a long tendon with origin on the ischialtuberosity of hip, inserts on the tibia with action that flexes the knee and extends the hip. Semimembranosus - most medial hamstring with origin on ischial tuberosity of hip, insetion on tibia and action to flex the knee and extend the hip. Medial Compartment Primary action of muscles in medial compartment is to adduct the hip joint but can help with lateral rotation and flexion of the hip. Adductor magnus - large flat muscle of the medial thigh with origin on pubis and ishium of hip, insertion on linea aspera on femur and has an action to adduct the hip. Adductor longus - flat muscle of medial thigh with origin on publis of hip, insertion on linea asperaof femur and action to adduct and laterally rotate the hip. Adductor brevis - short muscle of medial thigh with origin on pubis of hip, insertion on linea asperaof femur and action to adduct and laterally rotate hip. Gracilis - long thin muscle on medial side of the thigh with origin on pubis of hip bone, insertion on tibia and action to adduct the hip and flexes the knee.

Appendicular Skeleton

The word "append" means to hang, thus the appendicular skeleton comprises those skeletal components which hang or dangle from our torso, i.e., arms, hands, legs and feet plus their supporting structures, the pectoral and pelvic girdles. Pectoral Girdle and Upper Limbs The Pectoral Girdle is composed of the clavicle and scapula. The Humerus of the upper arm articulates with both bones. Radius (thumb side) and ulna (little finger side) of forearm articulate with the humerus to form the elbow joint. We have a great range of movement at the pectoral girdle site of articulation of the upper arm because the pectoral girdle is relatively loosely attached to the body frame (axial skeleton). It is vulnerable, however, to damage from strong blows or from falls. The Proximal end of the ulna forms the elbow. At the wrist joint, tendons are enclosed in sheaths which can become inflamed due to repetitive movements, such as typing, to produce carpal tunnel syndrome.

The Muscular System

Muscle cells in general have the common property of being able to contract (become shorter). Skeletal muscles contract in response to nervous stimulation but if the nerves are cut, the muscle will not contract unless stimulated artificially. Cardiac muscle responds to nervous stimulation to speed up or to slow down the contraction rate and if nerves are cut to the heart, muscle contraction still occurs. Cardiac muscle can contract on its own but needs nervous stimulation to increase or slow down heart rate. Smooth muscle contracts more slowly and responds to nervous stimulation and hormones.

Pelvic Girdle and Lower Extremities

The Pelvic girdle is larger and more basin-like in females than males for child bearing and birth. The Femur is the largest bone in the body and fits in a deep socket in the side of the pelvic girdle. The Tibia of the lower leg forms the "shin bone"; the fibula is more delicate and is not a weight-bearing bone of the leg but serves as a site for muscle attachment. The Patella is the kneecap and covers the vulnerable knee joint. Various ligaments in the knee joint can be torn or even separated due to injuries, especially while playing certain sports.

Actions of Skeletal Muscles

The body possesses over 600 muscles and their contraction produces movement. Gross movement of limbs and other parts of the body is the result of many muscles contracting through controlled and coordinated movements by groups of muscles as opposed to a muscle acting alone. Muscles many times attach to bones or soft tissue via tendons and usually attach at least to two points which most times spans a joint. The origin of a muscle is the attachment point that doesn't move and the insertion of a muscle is on the bone or soft tissue that moves is usually the most distal attachment. For the following discussion of classes of levers, be sure to review the definitions given in text for terms such as lever, fulcrum, effort and load. Classes of Levers and Examples the class of lever is dependent upon the position of the fulcrum in relation to the effort (force) and the load being moved. First class levers - in this class, the fulcrum is between the effort or force and the load. An example is the nodding movement at the atlantico-occipital joint. Second class lever - in this class, the load is placed between the fulcrum and the effort (force). An example is raising your heel from the ground. Third class lever - in this class, the effort (force) is between the fulcrum and the load. An example is the elbow joint.

BONES OF THE LOWER LIMB

The lower limb (appendicular skeleton) is connected to the axial skeleton by the pelvic girdle. The hip bones are known by several names but we'll refer to the collection of bones as the pelvis. The female pelvis is more round and wider than the male pelvis to permit passage of the head of the infant during childbirth. Hip Bone Each hip bone is made up of three bones - the ilium, ischium and pubis. It forms three articulations - sacroiliac joint with sacrum, pubic symphysis with the pubic cartilage and the hip joint with the head of the femur. Ilium: largest of hip bones, most superior edge known as the crest serves as attachment sites for abdominal muscles and can be palpated as the superior edge of the hip. The anterior superior iliac crest is a small projection at the most anterior point of the iliac crest and can also be palpated at the most anterior edge of the crest. This is the site of what is commonly known as a hip pointer, a painful injury following a blow to this region. Pubis smallest bone of hip, articulates with pubis bone on other side of pelvis. Ischium Tuberosity: large, roughened tuberosity on posteroinferior portion of ischium that provides attachment site for hamstring muscles. The ischial tuberosity is also palpable and is the site of the pelvis that we sit on. The Obturator formamen is a large foremen (hole) formed by the pubis and the ischium. The acetabulum is the cup-shaped depression formed by the ilium, ischium and pubis for articulation with the head of the femur. Femur Femur is the largest bone of the body and is located in the thigh. It articulates with the hip joint via the acetabulum, the knee joint with the tibial condyles and the knee via the posterior surface of the patella. The greater trochanter of the femur can be palpated on the side of the hip region. At the femur's most distal region, you can also palpate the lateral condyle located on the lateral surface of the knee joint and this articulates with the lateral tibial condyle, The medial condyle of the femur is located at the distal end and can be palpated in the medial portion of the knee joint where it articulated with the medial tibial condyle. Patella The patella is the largest sesamoid bone in the body and is embedded within the tendon of the quadriceps femoris muscle anterior to the knee joint. Tibia The tibia is the thicker bone of the leg and is the weight bearing leg bone. The anterior border can be palpated and is known as the "shin bone". The lateral and medial condyles can be palpated and articulate with the femur. The tibial tuberosity is located on the anterior aspect of the upper end of the tibial shaft and is the site for attachment of the patellar ligament. When you kneel on your knees, you are actually kneeling on your tibial tuberosity. The medial malleolus is located at the most distal end of the tibia and can be palpated as the bump on the medial portion of the ankle. Fibula The head of the fibula is located on the lateral surface of the knee and can be palpated. The lateral malleolus is located at the most distal region of the fibula in the lateral surface of the ankle. It articulates with the talus bone of the ankle. Bones of the foot Foot: composed of seven tarsal bones (all sesamoid), five metatarsals (miniature long bones) and two or three rows of phalanges (miniature long bones). Talus articulates with the tibia and fibula. The calcaneus is the largest tarsal bone and forms the heel on the foot.

MUSCLES OF THE HAND

Thenar group of muscles control the movement of the thumb in all directions. Hypothenar group of muscles control the movement of the little finger. Compartments of the upper limb - muscles of the upper limb are divided into compartments formed by layers of fascia which binds the muscles and forms septa between muscle groups.

MUSCLES OF THE BODY

There are over 600 muscles in the human body. For our study, I have chosen about 60 or so muscles for our study and I have listed them below according to their body locations. For the muscles below, you are expected to know their location, insertion, origin and action. Be sure to utilize the online text to see these muscles in their body location and to note what they move when they contract and to what bones and other body parts they are attached. Also keep in mind that movement of the body parts or regions is the result of more than one muscle contracting

Joints

There are three major types of Joints based on morphology (structure): Synovial joint are joints which have capsules that secrete slippery synovial fluid into joint to make movement more easy.Examples of synovial joints are the "ball and socket" joints - femur to pelvic girdle and hinge-like joints such as the knee or elbow joint Cartilaginous joints - cartilage fills space between bones, not much movement such as with breastbone (sternum) and some ribs Fibrous joints - fibrous tissue connects bones of fetal skull, permitting brain to grow after birth. This gives rise to "soft spots" on baby's head. These joints harden into sutures later when brain growth ceases. Joints may also be classified based on their function: Synarthroses - joints that do not provide any movementExample of synarthroses is the sagittal suture between two parietal bones. Amphiarthroses - joints that only provide a small degree of movementExample of amphiarthroses is the intervertebral joints between vertebral bodies. Diarthroses - joints that allow free movements such as the knee or shoulder joiints. In your online Anatomy & Physiology text, read and study information on anatomy of Synovial Joints under the topics - Articular cartilage, Synovial cavity, Articular capsule, Synovial fluid, Accessory ligaments, Articular fat pad and Bursae and tendon sheaths. Movements Possible about a Synovial Joint Abduction - adduction: Abduction is moving an arm or leg away from the body, adduction is moving arm or leg toward the body. With fingers - spreading fingers is abduction, bringing fingers together is adduction. Flexion - extension: Flexion is bringing two bones closer together, extension is widening the angle between two bones. Hyperextension is widening the angle between two bones more than the normal amount. Elevation - Depression: Elevation moves bone vertically upward such as lifting the scapula. Depression moves bone vertically downward such as lowering the scaplula downlwards. Protraction - Retraction: Moves a joint horizonatally forward such as moving the scauplaforward. Retraction moves a joint horizontally backwards such as moving the scapula backwards. Lateral excursion - Medial excursion: Lateral excursion moves mandible laterally. Medial excursion moves mandible medially. Circumduction - moving the arm in as wide a circle as possible. Combination of flexion, extension, abduction and adduction. Rotation: Moves a bone around its axis such as moving the head left and right as in saying no. Lateral rotation - Medial rotation: Turns a bone laterally on its longitudinal axis such as lateral rotation of the forearm. Medial rotation turns a bone medially on its longitudinal axis such as in medial rotation of the forearm. Supination - Pronation: Supination rotates forearm and hand and the foot and ankle upwards as in rotating the forearm so that the palms face upwards or in the anterior direction. Pronation rotates forearm and hand or the foot and ankle downwards such as rotating the forearm so the palms face downward or backward. Opposition - Reposition: Opposition moves the thumb towards the fingertips and reposition moves the thumb away from the fingertips. Dorsiflexion - Plantarflexion: Dorsoflexion flexes the ankle joint (moves foot to close angle between foot and leg). Plantarflexion extends ankle joint (moves foot away from leg). Inversion - Eversion: Inversion lifts medial side of the foot (twisting foot so that sole faces inward toward center line of the body. Eversion lifts lateral side of foot so that sole faces outward away from the center line of the body.

An elastic cartilage model of the long bone forms first 1. true 2. false

2. False

How many molecules of ATP are produced by the catabolism of one creatine phosphate molecule? 1. 1 2. 5 3. 2 4. 3 5. 4

1. 1

Which of the following statements best describes what happens during the initial phase of muscle contraction. 1. Creatine phosphate passes phosphate quickly to ADP to make more ATP 2. glucose and fatty acids delivered from bloodstream provides source of energy for ATP production. 3. glycolysis will begin and accumulate ATP and lactic acid until muscle contraction ceases due to cramping 4. aerobic respiration of glucose from glycogen (stored in muscle) generates needed ATP

1. Creatine phosphate passes phosphate quickly to ADP to make more ATP

Which movement about a synovial joint describes the moving the arm or leg away from the body? 1. abduction 2. adduction 3. retraction 4. supination 5. pronation 6. protraction

1. abduction

If strenuous muscle contraction continues and oxygen runs out, what statement best describes what happens next. 1. glycolysis will begin and accumulate ATP and lactic acid until muscle contraction ceases due to cramping 2. aerobic respiration of glucose from glycogen (stored in muscle) generates needed ATP 3. Creatine phosphate passes phosphate quickly to ADP to make more ATP 4. glucose and fatty acids delivered from bloodstream provides source of energy for ATP production.

1. glycolysis will begin and accumulate ATP and lactic acid until muscle contraction ceases due to cramping

Which bone can you feel in your leg that is commonly known as the shin bone? 1. tibia 2. fibula 3. talus 4. femur 5. calcaneus

1. tibia

Identify the large muscle on the back of the arm with three heads that have an origin on the scapula and humerus and insertion on the olecranon of the ulna. 1. triceps brachii 2. latissimus dorsi 3. brachial 4. biceps brachii 5. pectoralis major

1. triceps brachii

"A bands" are contained entirely within a sarcomere. 1. true 2. false

1. true

Ligaments connect bone to bone at places called joints 1. true 2. false

1. true

The long tubular shaft of a long bone is called what? 1. metaphysis 2. diploe 3. epiphysis 4. diaphysis 5. medullary cavity

4. diaphysis

Which thin muscle of the posterior forearm divides into four thin tendons distally with an origin on the ulna, insertion on phalanges 2 - 5 and an action to flex the wrist and fingers 2 - 5? 1. brachioradialis 2. flexor pollicis longus 3. pronator teres 4. flexor digitorum superficialis 5. flexor digitorum profundus

5. flexor digitorum profundus

THE DIAPHRAGM

Diaphragm is a dome-shaped musculofibrous sheet dividing the thorax from the abdomen. I t has openings for the inferior vena cava, esophagus and aorta. Origin is on the xiphoid process of the sternum, costal part of ribs 6 - 12, lumbar part (bodies) of L1 - L3, insertion on central tendon and action of when contracted, the dome flattens and lowers the floor of the thorax increasing the size lowering the pressure in the thoracic cavity and external air then is drawn into the lungs.

Bone Remodeling Over Time

During growth years, as the long bones such as the femur grow wider, osteoclasts dissolve bone inside the shaft and osteoblasts lay down new bone on the outside of the shaft. This permits bone to grow in width without accumulating excess weight. In later years, especially in women, osteoporosis may set in which bone loss of Calcium may occur faster thereby weakening bones of the hip and spine. Exercise may help to counter bone loss of mass especially in the younger years.

Muscle Function

Each skeletal muscle fiber is filled with myofibrils composed of large polymers of actin and myosinfilaments. A myofibril is composed of large polymers of the contractile proteins, actin and myosin. Many myofibrils form one muscle cell. The contractile unit in a muscle myofibril is the sarcomereand many sarcomeres are lined up sequentially in a muscle myofibril. A sarcomere is the area formed between two Z-lines. If you understand what happens in one sarcomere, you can understand how the entire muscle contracts. See online A & P text in Unit Muscular System, Contraction section for contracted and relaxed sarcomere. In the contraction process, the z-lines of a sarcomere move closer together with the actin filaments sliding over the myosin filaments. The myosin molecules in the large filaments have cross-bridges that, with the action of ATP as the energy source, ratchet the actin filaments toward each other. *Refer to the Physiology section - Muscle Contraction Cycle of the Muscular System unit in the online A & P text. Note the following points about the "sliding filament" hypothesis of muscle contraction. In ATP hydrolysis, the myosin head comes closer to the actin filament with the ADP and remaining phosphate group is attached to the myosin filament. In Crossbridge Formation , the myosin heads now attach to the actin filaments to form crossbridges with the remaining phosphate group being released. In the Power Stroke phase, the myosin head tilts toward the center of the sarcomere, releases ADP and slides the actin filaments along with it. In the Detachment of Myosin from Actin phase, , the myosin "head" contains an enzyme, ATPase, which breaks down ATP to ratchet (move) the actin filament forward as long as ATP is present. The breakdown of ATP releases the myosin "head" from the actin to start the ratcheting process all over again to continue contraction cycle. In the myosin "head", the enzyme called ATPase breaks down ATP causing release of myosin from actin. Without ATP, myosin remains attached to actin and accounts for "rigor mortis", the hard contraction of muscles after death when no more ATP is being made. This means that ATP is actually needed to cause muscles to relax rather than to

MUSCLES INVOLVED IN RESPIRATION

External intercostals - fibers run obliquely from the bottom of one rib to the top of the adjacent rib. Origin - inferior borders of ribs 1 - 11, Insertion - superior borders of ribs 2 - 12 and action of increasing size of thorax by drawing ribs upwards and outwards and are most active during inspiration. Internal intercostals - lie between external and innermost muscles and run obliquely backwards from bottom of one rib to top of adjacent rib. Origin - inferior borders of ribs and costal cartilages 1 - 11, insertion - superior borders of ribs 2 - 12 with action of decreasing the size of the thorax by drawing ribs downwards and inwards and are most active during expiration. Innermost intercostals - origin on internal aspect of ribs 1 - 11, insertion on internal aspect of ribs 2 - 12 and action of stiffening the chest wall during respiration and are most active during expiration.

Smooth Muscle

Individual smooth muscles have only one nucleus per cell and usually display a long slender form. Smooth muscle fibers normally are arranged in bundles such that the thick portion of the fiber lies alongside the thin portion of the next fibers. The myofibrils in smooth muscle are not arranged in as orderly a fashion as they are in striated or skeletal muscle so there is no noticeable striated appearance. Smooth muscles also contain many mitochondria located near the myofibrils to supply ATP for contraction. The myofibrils in smooth muscle are formed from many myofilaments and are made up of two contractile proteins, actin and myosin, as are the myofilaments in striated and cardiac muscle fibers. In areas where smooth muscle fibers are arranged in bundles, such as in the intestine, reticular fibers form a network which wraps itself around individual muscle fibers. These reticular fibers are embedded within a protein-polysaccharide material which appears similar to the basement membrane. Since these reticular fibers connect to the surrounding connective tissue, when the smooth muscle cells contract, the force of contraction is transmitted to the surrounding connective tissue enabling the entire tissue and organ to contract. Intermediate filaments are arranged inside the cell along the membrane in a crossing pattern such that when the myofibrils contract, they pull on the intermediate filaments and produce a shortened cell that has many bulges. At the light microscope level, when smooth muscle cells are fixed in the contracted state, their nuclei appear wavy. Smooth muscle in various parts of the body also differ in their physiological response to hormones such as seen with oxytocin and vasopressin (produced by the pituitary gland). 1. Oxytocin causes contraction of the smooth muscle of the uterus in terminal stages of pregnancy 2. Vasopressin causes contraction of smooth muscle surrounding walls of arterioles and can thus increase blood pressure This differential response to smooth muscle in different areas of the body to the same hormone indicates that the sarcolemma of smooth muscle cells in different parts of the body must differ with respect to their receptor molecules in the sarcolemma. Another characteristic of smooth muscle cells is that they will contract upon stretching. In the bladder, intestine or stomach, when a certain degree of distention occurs, the muscle fibers will contract, which in the case of the bladder can be distressing at times.

MUSCLES OF THE LEG

Most leg muscles are involved in moving the ankle and toes. Muscles are also located in compartments but not all muscles or compartments will be covered here. Posterior Superficial Compartment Gastrocnemius - together with soleus, it forms the bulk of the calf musculature. It originates on the medial condyle (medial head) and lateral condyle (lateral head) of the femur, insertion on the calcaneus with action of flexing the knee and plantarflexes the ankle. Soleus - together with the gastrocnemius, it forms the Achilles tendon with origin on tibia and fibula, insertion on calcaneus and action to plantarflexes the ankle. Posterior Deep Compartment Popliteus - leg muscle acting on knee joint with origin on lateral condyle of femur, inserts on tibia and action is to rotate femur laterally. Flexor digitorum longus - becomes tendinous at back of ankle where it travels to sole of foot and divides into four tendons. Origin is the shaft of the tibia, inserts on the distal phalanges 2 - 5 with action to cause plantarflexion of the ankle and flexes the four lateral toes. Flexor halluncis longus - deep in calf, becomes tendinous at back of ankle and travels into sole of foot with origin on the shaft of fibula, insertion is on the distal phalanx of hallux and action is flexionof the big toe.

Bones of the forearm

Radius: lateral bone of forearm (remember, arm is in anatomic position) which has several points of articulation. The Humeroradial joint with the capitulum of the humerus, the superior radioulnar joint with the radial notch of ulna, the middle radioulnar joint with the shaft of the ulna via the interosseous membrane and the radiocarpal joint with the scaphoid, lunate and triquetral bones of the carpal portion of the hand. Ulna: is the medial forearm bone and also has five articulations. The humeroulnar joint with the trochlea portion og humerus, the superior radioulnar joint with the head of the radius, the middle radioulnar joint with the shaft of the radius via the inteosseous memberane and the ulnocarpal joint with the carpal bones via the articular disc

MUSCLES OF THE SHOULDER

Shoulder is formed by the pectoral girdle and connects the upper limb to the axial skeleton. The rotator cuff is the name given to a complex of four muscles that orinate and insert into the greater and lesser tubercles of the humerus. The rotator cuff tendons blend with each other as well as the articular capsule of the shoulder joint to help reinforce it. The rotator cuff helps the shoulder to move and is also important to holding the head of the humerus within the glenoid cavity of the scapula. Supraspinatus - one of rotator cuff muscles, this thick muscle occupies the top of the scapula with an origin on the supraspinous fossa of the scapula, insertion on the greater tubercle of the humerus and action to abduct the arm Infraspinatus - one of rotator cuff muscles, this large, triangula muscle occupies back of the scapula with an origin on the infraspinous fossa of the scapula, insertion on the greater tubercle of the humerus and an action that extends and laterally rotates the arm Teres minor - one of the rotator cuff muscles, it is long and rectangular with an origin on the lateral border of the scapula, insertion on the greater tubercle of the humerus and adducts and laterally rotates the arm Subscapularis - one of four rotator cuff muscles, it is large, triangular muscle occupying the front of the scapula with an origin on the subscapular fossa of the scapula, insertion on the greater tubercle of the humerus with an action of adducting and laterally rotating the arm. Deltoid - thick, powerful muscle that covers the shoulder joint and upper humerus with an origin on the clavicle, spine of the scapula and acromion of the scapula, insertion on the deltoid tuberosity of the humerus and an action of abducting the shoulder. Teres major - forms part of the posterior wall of the axilla with the latissimus dorsi. It has an origin on the inferior angle of the scapula, inserts on the intertubercular groove of the humerus and has an action of extending the shoulder joint and adducts and medially rotates the humerus. Coracobrachialis - located on the front of the arm, its origin is on the coracoid process of the scapula, inserts on the humerus and has an action of flexing the shoulder and adducting the arm.

MUSCLES INVOLVED IN MOVING HEAD AND NECK

Sternocleidmastoid - long, thick muscle located on the side of the neck with an origin on the clavicle and manubrium of sternum, insertion on the mastoid process of temporal bone and an action of flexing neck if both muscles act together or drawing head toward one shoulder if one acts individually. This muscle runs underneath the platysma. If the head is held in a fixed position, contraction of both sternocleidomastoid muscles raises the thorax and aids in forced inspiration (heavy breathing such as following exercise). You can palpate these muscles by pushing your chin up with your hand as you try to force your head down to your chest. Semispinalis capitis - a thin muscle of the posterior neck with an origin on the spinous processes of T3 - T6 vertebra, insertion on the C1 - C3 transverse processes and action of extending neck if both contract together and flexing and rotating the ehad if each muscle acts individually. MUSCLES OF THE TRUNK - contains muscles concerned with the movement of the vertebral coumn, respiration and control of intr-abdominal pressure. Muscles of the Abdomen - are important flexors of the vertebral column and responsible for increasing intra-abdominal pressure in processes like coughing, urination, defecation, childbirth, vomiting and respiration. Rectus abdominis - strap-like muscle on front of abdomen enclosed in rectus sheath with three tendinous insertions in each belly to form the "six pack". The origin is on the pubis of the hi bone, insertion is one the xiphoid process of the sternum and costal cartilages 5 - 7 and action whic flexes the vertebral column and increases intra-abdominal pressure External oblique - outer layer forming the sidewalls of the abdomen whose inferior border forms the inguinal ligament. The origin is on ribs 5 - 12 and the iliac crest of the hip bone, insertion is one the pubis of the hip bone and the linea alba and has an action to flex and rotate vertebral column and increases intra-abdominal pressure. Internal oblique - is the middle layers forming the sidewalls of the abdomen. Origin is one the thoracolumbar fascia, iliac crest of hip bone and the inguinal ligament, insertion on costal cartilages 9 - 12, line alba and xiphoid process of the sternum with an action of flexing and rotating the vertebral column and increases intra-abdominal pressure. Transversus abdominis- the innermost layer forming the sidewalls of the abdomen. Origin is lower costal cartilages, iliac crest of hip bone and inguinal ligament, insertion on costal cartilages 9 - 12, linea alba and xiphoid process of sternum with an action of flexing and rotating vertebral column and increases intra-abdominal pressure. Rectus sheath - tendons of abdominal muscles merge together at front of abdomen to form a fibrous sheath with a mid-portion known as the linea alba Inguinal ligament - forms along bottom edge of external oblique to create a tunnel which in females is the site for passage of the round ligaments of the uterus and in males the spermatic cord and other femoral vessels and nerves passing into the thigh.

MUSCLES OF MASTICATION

Temporalis - large, fan-shaped muscle on lateral surface of head with origin on temporal bone, insertion on coronoid process of mandible and action of elevating and retracting the mandible to allow for chewing. If you tightly close your jaw, this muscle may be felt contracting in the temporal region. Masseter - powerful muscle located on side of the face over jaw with origin on zygomatic bone, insertion on mandible (coronoid process) and action of elevating and retracting mandible. When jaw is tightly closed, this muscle bulges out near angle of jaw.

THORACIC CAGE

Thoracic cage formed from twelve thoracic vertebra, twelve ribs and the three bones of the sternum. Sternum: flat bone in middle of chest composed of manubrium, body and xiphoid process. The manubrium is the most superior portion of the sternum and articulates with the first and second ribs via their costal cartilages. The Body portion is the largest bone of the sternum and articulates with the costal cartilages of ribs 3 - 7. The Xiphoid process is the most inferior portion of the sternum.

When the diaphragm contracts, what happens to the air pressure inside the thoracic cavity? 1. stays the same 2. decreases 3. increases

2. decreases

What is the name for the cup-shaped depression on the side of the hip formed by the ilium, ischium and pubis? 1. acetabulum 2. iliac crest 3. ischial tuberosity 4. anterior superior iliac crest 5. obturator foramen

1. acetabulum

Two proteins, troponin and tropomyosin, are found along the surface of the __________ filaments. 1. actin 2. cross bridges 3. calcium ions 4. myosin

1. actin

Which one of the following muscles is multipennate? 1. omohyoid 2. deltoid 3. triceps brachii 4. pronator quadratus 5. rectis femoris

2. deltoid

Choose the action of the buccinator muscle. 1. keeps food from collecting between teeth and cheeks 2. closes eye as in winking 3. raises the upper eyelid 4. raises the upper lip as in smiling 5. closing and pursing the lips

1. keeps food from collecting between teeth and cheeks

The small round spaces which house the mature bone cells are called what? 1. lacunae 2. osteoblast 3. osteon 4. osteoclast 5. osteocyte

1. lacunae

A motor unit is a motor neuron and all the muscle cells that it innervates and causes to contract. 1. true 2. false

1. true

Acetylcholine is released from the tip of the motor neuron at the neuromuscular junction where it binds to receptors on the muscle membrane to cause the muscle fiber to contract. 1. true 2. false

1. true

All of the rotator cuff muscles insert on the greater tubercle of the humerus. 1. true 2. false

1. true

An epiphyseal plate of cartilage forms at either end of a long bone and is the future growth plate so bone may grow longer. 1. true 2. false

1. true

Yellow bone marrow is principally responsible for storing which one of the following substances? 1. glucose 2. triglycerides 3. glycerol 4. proteins

2. triglycerides

when you move your head up and down as in nodding yes to a question, what best describes the action of the atlas vertebra? 1. the atlas articulates with the axis 2. the atlas does not articulate with any bone 3. the atlas articulates with the superior articulating facet of the axis 4. the atlas articulates with the occipital condyles of the occipital bone

4. the atlas articulates with the occipital condyles of the occipital bone

which vertebral type does not posses a vertebral body? 1. first lumbar 2. T1- first thoracic 3. T2 - second thoracic 4. C2- second cervical 5. C1- first cervical 6. sacrum

5. C1- first cervical

pick the term below that best fits what a sulcus is. 1. a round hole through a bone 2. a cavity or recess in a bone 3. an opening of a canal through a bone 4. a slit through a bone 5. a bony groove that houses a tendon, nerve or blood vessel

5. a bony groove that houses a tendon, nerve or blood vessel

pick the term below that best fits what a sinus is. 1. a bony groove that houses a tendon, nerve or blood vessel 2. a slit through a bone 3. a rounded hole through a bone 4. an opening of a canal through a bone 5. a cavity or recess in a bone

5. a cavity or recess in a bone

In movements possible around a synovial joint, __________ describes the spreading of one's fingers. 1. adduction 2. extension 3. hyperextension 4. cicrumduction 5. flexion 6. abduction

6. abduction

Muscle Tension, Strength and Fatigue

Muscle tension is the collective force formed during contraction. A motor unit (see Contraction section of Muscular System in online A & P text.) is a motor neuron and all the muscle cells that it innervates and causes to contract. This means that one neuron innervates many skeletal muscle fibers and they all contract when that neuron stimulates them to contract. All or none principle for muscle fiber contraction - a threshold of stimulus activity must be reached before the muscle fiber will contract, but when it contracts, it does so with all its strength. Thus, a muscle (organ) exhibits graded contraction strength, i.e., the ability to contract strongly or weakly over a range of contraction strengths, by causing more and more muscle fibers (cells) to contract until all fibers are contracting and that is the limit of strength for that muscle. But, remember that each muscle fiber or cell (not muscle as an organ composed of thousands of muscle fibers or cells) contracts at its full strength or not at all, and a muscle fiber or cell does not exhibit graded muscle contraction

Aerobic exercise works muscles at a rate at which the body can keep them supplied with oxygen and results in what changes in the muscles being exercised? 1. all of the above 2. there is an increase in size and number of mitochondria 3. muscle tissues contain more of the oxygen-binding pigment myoglobin. 4. the number of blood capillaries in the muscle increases

1. all of the above

Skeletal muscle contraction requires ___________. 1. all of the above 2. arrival of a nerve impulse 3. ATP 4. calcium ions

1. all of the above

Choose the correct order for the stages of bone remodeling? 1. bone resting, bone resorption, bone reversal, bone formation, bone mineralization 2. bone reversal, bone formation, bone mineralization, bone resting, bone resorption 3. bone resorption, bone reversal, bone formation, bone mineralization, bone resting 4. bone formation, bone mineralization, bone resting, bone resorption, bone reversal

1. bone resting, bone resorption, bone reversal, bone formation, bone mineralization

Which of the following statements best describes what happens in muscle fibers after 5 - 10 minutes of strenuous exercise. 1. glycolysis will begin and accumulate ATP and lactic acid until muscle contraction ceases due to cramping 2. aerobic respiration of glucose from glycogen (stored in muscle) generates needed ATP 3. Creatine phosphate passes phosphate quickly to ADP to make more ATP 4. glucose and fatty acids delivered from bloodstream provides source of energy for ATP production.

2. aerobic respiration of glucose from glycogen (stored in muscle) generates needed ATP

Which of the muscles listed below are involved in increasing intra-abdominal pressure in processes like coughing, urination, defecation, childbirth, vomiting and respiration? 1. internal oblique 2. all of the listed muscles 3. transverse abdominis 4. rectus abdominis 5. external oblique

2. all of the listed muscles

Identify the small triangular muscle on the lateral side of the elbow with an origin on the lateral epicondyle of the humerus, insertion on the olecranon of ulna and action of extending the elbow. 1. pronator quadratus 2. anconeus 3. flexor pollicis longus 4. brachioradialis 5. extensor digitorum

2. anconeus

As the electrical impulse spreads over the muscle fiber at the start of contraction, it causes the sarcoplasmic reticulum (smooth ER) in the muscle fiber to release _____________ ions. 1. potassium 2. calcium 3. sodium 4. phosphate

2. calcium

Which one of the following types of contractile filaments found in the sarcoplasm of smooth muscles has a tropomyosin component? 1. intermediate filaments 2. thin filaments 3. thick filaments

2. thin filaments

What muscle forms the innermost layer of the sidewalls of the abdomen? 1. external oblique 2. transverse abdominis 3. rectus abdominis 4. internal oblique

2. transverse abdominis

Which of the following muscles act to extend the knee? 1. semimembranosus, sartorius 2. vastus medialis, rectus femoris 3. vastus medialis, biceps femoris 4. rectus femoris, semimembranosus 5. biceps femoris, sartorius

2. vastus medialis, rectus femoris

In movements possible around a synovial joint, __________ describes the movement of an arm or leg being moved closer to the body. 1. hyperextension 2. flexion 3. adduction 4. extension 5. abduction 6. circumduction

3. adduction

The combination of a Haversian Canal, concentric lamellae (rings around canal) and osteocytes is called what? 1. Haversian System 2. osteon 3. all of the above

3. all of the above

In which one of the following stages of a twitch contraction does crossbridge formation occur? 1. latent period 2. relaxation period 3. contraction period

3. contraction period

Which one of the following is not one of the common properties associated with all muscles? 1. extensibility 2. electrical excitement 3. convertibility 4. contractility 5. elasticity

3. convertibility

What is the action of the temporalis muscle? 1. keeps food from collecting between teeth and cheeks 2. raises the upper lip as in smiling 3. elevates and retracts the mandible 4. closes eye as in winking 5. closing and pursing the lips

3. elevates and retracts the mandible

In movements possible around a synovial joint, __________ describes the movement which causes the angle between two bones to widen. 1. circumduction 2. flexion 3. extension 4. hyperextension 5. abduction 6. adduction

3. extension

Which one of the following best describes the action of the triceps brachii? 1. flexion of the elbow and shoulder 2. adduction and medial rotation of the humerus 3. extension of the elbow and adduction of the arm 4. flexion of the shoulder and adduction of the arm 5. supination of the forearm

3. extension of the elbow and adduction of the arm

Which of the thorax muscles below are most active during inspiration (breathing in)? 1. internal intercostals 2. innermost intercostals 3. external intercostals

3. external intercostals

What is the action of the iliacus and psoas major muscles of the hip? 1. flexing the leg 2. extending the hip and trunk 3. flexing and abducting the hip and flexing the trunk 4. extending the leg

3. flexing and abducting the hip and flexing the trunk

The roof of the orbits along with the supercilliary arch are regions of what bone? 1. sphenoid 2. ethmoid 3. frontal 4. temporal (tympanic part) 5. occipital

3. frontal

What is the insertion of the gluteus maximus? 1. greater trochanter of femur 2. lesser trochanter of femur 3. gluteal tuberosity 4. acetabulum 5. tibial tuberosity

3. gluteal tuberosity

If the left sternocleidomastoid muscle contracts and the right does not, what action results? 1. head moves to right 2. head moves down toward the ground 3. head moves to left 4. head move up toward the ceiling

3. head moves to left

Which muscle of the shoulder and shoulder girdle has an origin of T1 - T12 spinous processes, iliac crest and ribs 9 - 12 and inserts on the humerus with an action of extending, adducting and medially rotating the arm at the shoulder joint? 1. triceps brachii 2. brachialis 3. latissimus dorsi 4. biceps brachii 5. pectoralis major

3. latissimus dorsi

What is the insertion for the masseter muscle? 1. temporal bone 2. zygomatic bone 3. mandible (coronoid process) 4. maxilla bone 5. nasal bone

3. mandible (coronoid process)

Where would you expect to find the epiphyseal plate in a long bone? 1. epiphysis 2. diaphysis 3. metaphysis 4. diploe 5. medullary cavity

3. metaphysis

Which two of the following are contractile proteins present in skeletal muscle? 1. myosin and troponin 2. actin and titin 3. myosin and actin 4. myosin and actin 5. troponin and actin

3. myosin and actin

Which of the muscles listed below is located on the anterior chest wall, inserts on the scapula and has an action of pulling the shoulder girdle forwards and downwards? 1. triceps brachii 2. trapezius 3. pectoralis minor 4. serrates anterior 5. biceps brachii

3. pectoralis minor

Which leg muscle below acts on the knee joint with origin on the lateral condyle of femur, insertion on the tibia and action of rotating femur laterally? 1. flexor halluncis longus 2. flexor digitorum longus 3. popliteus 4. soleus 5. gastrocnemius

3. popliteus

From the list below, choose the correct term for a muscle that is primarily responsible for instigating a particular movement, such as the role of the triceps brachii in extending the elbow? 1. synergist 2. protagonist 3. prime mover 4. fixator 5. antagonist

3. prime mover

Choose the action of the zygomaticus minor muscle. 1. closing and pursing the lips 2. keeps food from collecting between teeth and cheeks 3. raises the upper lip as in smiling 4. raises the upper eyelid 5. closes eye as in winking

3. raises the upper lip as in smiling

Which of the following muscles does not insert on the tibial tuberosity via the patellar tendon? 1. vastus lateralis 2. vastus medialis 3. sartorius 4. rectus femoris 5. vastus intermedius

3. sartorius

The acromial end of the clavicle articulates with which one of the following bones? 1. sternum 2. 1st rib 3. scapula 4. humerus

3. scapula

Overview of Skeleton

Bone remodeling occurs during the first 20 or so years of life. Bones are organized into two major divisions: Axial Skeleton - bones of skull, rib cage, and vertebral column Appendicular Skeleton - bones of Pectoral Girdle (shoulder) and upper extremities (arms), bones of Pelvic Girdle and lower extremities (legs). Ligaments connect bone to bone at places called joints. Tendons connect muscles to bone or sometimes muscles to other muscles. Axial and Appendicular Skeleton (See Online Anatomy & Physiology text) Axial Skeleton The Skull - composed of bones that protect the brain, inner ear and eyes. Provide jaws for attachment of teeth. Bridge of nose only boney part, rest of nose is cartilage. Sinuses are air spaces in bones such as the temporal that lighten the skull. Sinusitus sometimes occurs when bacterial infections invade sinuses causing trapped air to expand with low pressure externally causing headaches and discomfort in bones surrounding eyes. Vertebral column protects spinal cord from base of skull to pelvic girdle. Intervertebral disks support each vertebra and may be herniated or ruptured when undue stress is placed on them. Soft gel-like core of a disk may pop through (herniate) and place pressure on spinal nerves in that area causing pain and discomfort. Ribs connect to sternum to offer protection to lungs and heart.

Vertebra Types

Cervical Vertebra: C1 is the atlas (remember that in Greek mythology, the God Atlas supported the heavens on his shoulders). The atlas does not have a body and is shaped like a ring of bone that articulates with the occipital bone of the cranium. C2 is the Axis which has the body of the C1 vertebra fused to its body to form an upward projection called the dens and the Atlas vertebra rotates around the dens. This means that when you move your head from right to left or left to right as in signifying "no", your C1 atlas is articulating with the C2 axis but when you nod your head up and down as in meaning "Yes", you are now articulating the atlas with the occipital condyles of the occipital bone of the skull. The transverse process on the cervical vertebra has a transverse foramen for the passage of the vertebral arteries to the brain. Only the cervical vertebra have transverse foramen. Thoracic Vertebrae (12): form the vertebral column of the thorax and possess facets on their transverse process for articulation with the ribs. Only the thoracic vertebra possess rib articulation facets on their transverse process. Lumbar Vertebra: are the largest vertebra with the largest body portion of all the vertebra due to these vertebra forming the main focal point for the weight of the upper body. Sacrum and Coccyx: five sacral vertebra fuse to form a triangular sacrum and from 3 - 5 coccygealvertebra fuse to form the coccyx. The sacrum articulates laterally with the hip bones.

Coordination of Movement

Muscles work together to produce a movement but usually one muscle may produce more of the movement than the others. The muscle doing the most for a movement is called the prime mover or agonist. Muscles that work in opposition to the prime mover and are known as antagonists. Prime mover (agonist) - muscle that is primarily responsible for a particular movement. Example is the triceps brachii being the prime mover in the extension movement at the elbow. Anatagonists - is the opposite of a prime mover and acts in opposition to the prime mover. An example is the biceps brachii being the antagonist to the triceps brachii and functions to flex the arm at the elbow. Synergists - a muscle that assists the prime mover by stabilizing and reducing any unwanted movement and acts to promote the same movement as that of the prime mover. An example is the brachialis as it works to flex the arm at the elbow and helps the biceps brachii to do this. Fixator - a muscle that holds the proximal end of another muscle, usually the prime mover, in place and helps the prime mover to act more efficiently. An example is the rotator cuff, latissimus dorsiand major pectoral muscles act together as fixators of the shoulder joint.

The function of amphiarthroses can be best described by which one of the following? 1. allows a small degree of movement 2. provides no movement 3. allows free movement

1. allows a small degree of movement

What happened to the body portion of the atlas (C1 vertebra)? 1. became attached to axis (C2) body to form dens 2. became attached to occipital condyles 3. disappeared during the fetal maturation process 4. became attached to the first thoracic

1. became attached to axis (C2) body to form dens

Which movement about a synovial joint describes lifting the scapula upwards? 1. elevation 2. extension 3. depression 4. flexion 5. plantar flexion 6. dorsiflexion

1. elevation

is the radius on the medial or lateral side of the forearm when the arm is in the anatomic position? 1. lateral 2. medial

1. lateral

identify the large foramen formed by the pubis and the ischium in the hip? 1. acetabulum 2. ischial tuberosity 3. iliac crest 4. anterior superior iliac crest 5. obturator foramen

5. obturator foramen

This bone forms the back and base of the skull and contains the foramen magnum. 1. sphenoid 2. temporal (tympanic part) 3. ethmoid 4. frontal 5. occipital

5. occipital

Which one of the following ions is released into the cytosol of muscle fibers in response to an action potential and plays a key role in skeletal muscle contraction? 1. calcium 2. potassium 3. sodium 4. phosphate 5. chloride

1. calcium

What type of joint does not show much movement and is located between the breastbone (sternum) and some of the ribs? 1. cartilaginous 2. synovial 3. fibrous

1. cartilaginous

What is the insertion for the diaphragm? 1. central tendon 2. lumbar part of L1 - L3 3.xiphoid process of sternum 4. costal part of ribs 1 - 6

1. central tendon

Which one of the following terms describes the sheet of thick connective tissue that surrounds the entirety of a skeletal muscle? 1. epimysium 2. perimysium 3. hypomysium 4. automysium 5. endomysium

1. epimysium

Which one of the following is the term used to describe the ability of a muscle to stretch without injury? 1. extensibility 2. contractility 3. excitability 4. convertibility 5. elasticity

1. extensibility

Which one of the following muscle groups acts to increase the size of the throrax by drawing the ribs upwards and outwards? 1. external intercostals 2. diaphragm 3. internal intercostals 4. innermost intercostals 5. transverse abdominis

1. external intercostals

What muscle forms the outermost layer of the sidewalls of the abdomen? 1. external oblique 2. internal oblique 3. transversus abdominis 4. rectus abdominis

1. external oblique

Which terms below best describe the joints that become the sutures in the skull? 1. fibrous and synarthroses 2. cartilaginous and amphiarthroses 3. synovial and diarthroses 4. synovial and synarthroses 5. fibrous and diarthroses

1. fibrous and synarthroses

Which one of the following bony features is best described as a small pit or depression that provides attachment for muscles and ligaments? 1. fovea 2. trochanter 3. crest 4. eminence 5. spine

1. fovea

Which movement about a synovial joint describes twisting the foot so that the sole faces inward toward the center line of the body? 1. inversion 2. protraction 3. adduction 4. pronation 5. abduction 6. retraction

1. inversion

Choose the correct classification for muscle contraction which involves no change in length or tension. 1. isometric contraction 2. eccentric isotonic contraction 3. concentric isotonic contraction 4. isotonic contraction

1. isometric contraction

What type of contraction describes a muscle that changes length but tension stays the same? 1. isotonic contraction 2. isometric contraction

1. isotonic contraction

Which of the following muscles form the deep layer of both the male and female pelvic floor? 1. levator ani, coccygeus 2. coccygeus, deep transverse perineal 3. bulbospongiosus, levator ani 4. coccygeus, bulbospongiosus

1. levator ani, coccygeus

Which part of the temporal bone has a large prominence for the insertion of the sternocleidomastoid muscles? 1. mastoid process 2. squamous part 3. tympanic part 4. petrous part

1. mastoid process

Of the three cranial fossae, which one is a depression formed by the sphenoid and temporal bones? 1. middle cranial fossa 2. anterior cranial fossa 3. posterior cranial fossa

1. middle cranial fossa

What is the insertion of the buccinator muscle? 1. modiolus 2. zygomatic bone 3. lesser wing of sphenoid 4. temporal bone 5. superior tarsus (eyelid)

1. modiolus

Which one of the following arteries is responsible for providing arterial blood to both the diaphysis and metaphysis of a long bone? 1. nutrient artery 2. metaphysical artery 3. periosteal artery 4. epiphyseal artery 5. nutrient vein

1. nutrient artery

A type of bone cell that helps to break down the bone matrix in the bone remodeling process is called what? 1. osteoclast 2. osteoblast 3. osteocyte 4. osteon 5. lacunae

1. osteoclast

Which of the quadriceps muscles below is the most anterior and originates on the anterior superior iliac spine and acetabulum of the hip bone. 1. rectus femoris 2. vastus lateralis 3. vastus intermedius 4. sartorius 5. vastus medialis

1. rectus femoris

Which one of the following carpal bones is located in the proximal row and lies lateral to the lunate bone? 1. scaphoid 2. capitate 3. pisiform 4. hamate 5. triquetrum

1. scaphoid

In addition to the gastrocnemius, what other leg muscle forms the Achilles tendon? 1. soleus 2. flexor digitorum longus 3. flexor halluncis longus 4. popliteus

1. soleus

What muscle has an origin on both the clavicle and sternum and an insertion on the mastoid process of the temporal bone? 1. sternocleidomastoid muscle 2. temporalis 3. masseter 4. semispinalis capitis

1. sternocleidomastoid muscle

What is the origin of the supraspinatus muscle in the shoulder? 1. supraspinous fossa of scapula 2. inferior angle of scapula 3. infraspinous fossa of scapula 4. subscapular fossa of scapula 5. lateral border of scapula 6. clavicle

1. supraspinous fossa of scapula

From a functional point of view, what type of joint provides no movement at all? 1. synarthroses 2. amphiarthroses 3. diarthroses

1. synarthroses

At the wrist joint, tendons are enclosed in sheaths which can become inflamed due to repetitive movements such as typing to produce carpal tunnel syndrome. 1. true 2. false

1. true

Hormones from the parathyroid gland are involved in releasing calcium from bone and also in storing it in bone 1. true 2. false

1. true

In later years, especially in women, osteoporosis may set in and bone loss of Calcium may occur faster thereby weakening bones of the hip and spine 1. true 2. false

1. true

Skeletal muscles contract in response to nervous stimulation but if the nerves are cut, the muscle will not contract unless stimulated artificially. 1. true 2. false

1. true

Spongy bone tissue is found in the head of long bones and in the flat bones of the skull and contains red bone marrow and participates in red blood cell production. 1. true 2. false

1. true

The braincase consists of the eight bones that surround your brain 1. true 2. false

1. true

The compression of intervertebral discs as we age results in loss of height and increased risk of pinched spinal nerves. 1. true 2. false

1. true

The diaphragm separates the thorax from the abdomen. 1. true 2. false

1. true

The force with which a skeletal muscle can contract is related to the length of its sarcomeres. 1. true 2. false

1. true

The lungs and heart are protected by the ribs, sternum and vertebral column. 1. true 2. false

1. true

The origin of the triceps is the scapula. 1. true 2. false

1. true

The tendons of the abdominal muscles merge together at the fron of the abdomen to form a fibrous sheath with a mid-portion known as the linea alba. 1. true 2. false

1. true

the pelvic girdle is larger and more basin-like in females than males for child bearing and birth 1. true 2. false

1. true

the ulna articulates with the radius by way of an interosseous membrane 1. true 2. false

1. true

Interstitial growth at the epiphyseal growth plate occurs at which one of the following zones of cartilage? 1. zone of proliferating cartilage 2. zone of resting cartilage 3. zone of calcified cartilage 4. zone of hypertrophic cartilage

1. zone of proliferating cartilage

pick the term below that best describes what a foramen is. 1. an opening of a canal through a bone 2. a round hole through a bone 3. a bony groove that houses a tendon, nerve or blood vessel 4. a cavity or recess in a bone 5. a slit through a bone

2. a round hole through a bone

what is the largest bone of the sternum? 1. diploid process 2. body 3. manubrium

2. body

Which one of the following terms best describes the shortening of a muscle while maintaining constant tension within that muscle? 1. eccentric isotonic contraction 2. concentric isotonic contraction 3. isometric contraction

2. concentric isotonic contraction

Which movement about a synovial joint describes moving the foot to close the angle between the foot and the leg? 1. flexion 2. dorsiflexion 3. plantar flexion 4. extension 5. depression 6. elevation

2. dorsiflexion

The epiglottis is an example of which one of the following types of cartilage? 1. fibrocartilage 2. elastic cartilage 3. hyaline cartilage

2. elastic cartilage

Which muscle below is located on the anterior forearm and divides into four tendons which insert on fingers 2 - 5 and act to extend the wrist and fingers 2 - 5? 1. pronator quadratus 2. extensor digitorum 3. ancones 4. flexor pollicis longus 5. brachioradialis

2. extensor digitorum

Along the bottom edge of the internal oblique, a tunnel is formed for passage of the round ligament in females. 1. true 2. false

2. false

At the cellular level, the loss of bone as we age is due to osteoclasts producing more bone than osteoblasts breakdown. 1. true 2. false

2. false

Bones are not considered organs because they do not contain the four basic tissue type 1. true 2. false

2. false

Cardiac muscles can only contract if they are stimulated by nerves or by artificial means. 1. true 2. false

2. false

Epiphyseal plate formation is the first step in long bone formation . 1. true 2. false

2. false

In muscle contraction, the actin ""head"" contains an enzyme, ATPase, which breaks down ATP to ratchet (move) the myosin filament forward as long as ATP is present. 1. true 2. false

2. false

Muscles composed of thousands of muscle fibers follow the all or none principle for contraction. 1. true 2. false

2. false

The all or none principle for muscle fiber contraction means that all the muscle fibers of a muscle contract or none do when the muscle is stimulated to contract. 1. true 2. false

2. false

The axial skeleton consists of the bones of the skull, pectoral girdle, rib cage, and vertebral column. 1. true 2. false

2. false

The function of the rotator cuff muscles is to hold the head of the humerus within the acromion fossa of the scapula. 1. true 2. false

2. false

The intervertebral foramen is the opening between the pedicles which allow for the passage of the spinal cord and meninges 1. true 2. false

2. false

The largest sinuses in the skull are located in the occipital bone. 1. true 2. false

2. false

The nose is formed mostly from bone. 1. true 2. false

2. false

When a sarcomere contracts, the myosin filaments slide over the actin filaments bringing the myosin filaments closer together. 1. true 2. false

2. false

When blood calcium level is low, PTH (parathyroid hormone) is released and stimulates osteoblasts to dissolve bone, releasing calcium. 1. true 2. false

2. false

Yellow bone marrow is in active formation of red blood cells and some types of white blood cells. 1. true 2. false

2. false

the Pectoral Girdle is composed of the clavicle, scapula and humerus. 1. true 2. false

2. false

Which muscle below is located deep in the calf, becomes tendinous at back of ankle and travels into sole of foot to insert on the distal phalanx and has an action to flex the big toe. 1. soleus 2. flexor halluncis longus 3. popliteus 4. flexor digitorum 5. gastrocnemius

2. flexor halluncis longus

Which thin muscle of the posterior forearm and thumb has its origin on the ulna, insertion on the 1st distal phalanx and action to flex the thumb. 1. flexor digitorum superficialis 2. flexor pollicis longus 3. flexor digitorum profundus 4. pronator teres 5. brachioradialis

2. flexor pollicis longus

What is the origin of the infraspinatus muscle in the shoulder? 1. lateral border of scapula 2. infraspinous fossa of scapula 3. inferior angle of scapula 4. supraspinous fossa of scapula 5. clavicle 6. sub scapular fossa of scapula

2. infraspinous fossa of scapula

In a healthy knee, what structure(s) does the synovial fluid come in contact with? 1. articular cartilage 2. articular capsule 3. articular fat pad 4. all of the listed options

4. all of the listed options

Choose the correct classification for muscle contraction which involves no change in length or tension. 1. concentric isotonic contraction 2. isometric contraction 3. isotonic contraction 4. eccentric isotonic contraction

2. isometric contraction

To which one of the following classes do bones that act as levers for the movement of skeletal muscle belong? 1. flat 2. long 3. irregular 4. short 5. sesamoid

2. long

Is the ulna on the medial or lateral side of the forearm when the arm is in the anatomic position? 1. lateral 2. medial

2. medial

Which one of the following types of cell is responsible for the initiation of the calcification process in bone? 1. osteogenic cell 2. osteoblast 3. osteocyte 4. osteoclast

2. osteoblast

what two bones does the clavicle articulate with? 1. scapula and humerus 2. scapula and manubrium 3. humerus and manubrium

2. scapula and manubrium

Which one of the following superficial muscles of the back elevates the ribs? 1. serratus posterior inferior 2. serratus posterior superior 3. quadratus lumborum

2. serratus posterior superior

Where does the frontal belly of the occipitfrontalis muscle insert? 1. occipital bone 2. skin of forehead 3. Galea aponeurotica 4. temporal bone 5. frontal bone

2. skin of forehead

Of the listed items below, which is not an origin for the deltoid muscle? 1. spine of the scapula 2. subscapular fossa of scapula 3. clavicle 4. acromion of the scapula

2. subscapular fossa of scapula

Which one of the following types of fibrous joint occurs when two bones are bound together by an interosseous ligament? 1. suture 2. syndesmosis 3. gomphosis

2. syndesmosis

a joint is a type of joint which has a capsule that secrete slippery synovial fluid into the joint to make movement more easy 1. cartilaginous 2. synovial 3. fibrous

2. synovial

Which tarsal bone does the fibula articulate with in the ankle region? 1. navicular 2. talus 3. cuboid 4. lateral cuneiform 5. calcaneus

2. talus

When you move your head from right to left and left to right as in signifying no when asked a question, what best describes the action of the atlas and axis? 1. the axis articulate with the occipital condyles 2. the atlas articulates with the axis 3. the atlas does not articulate with any bone 4. the atlas articulates with the occipital condyles of the occipital bone

2. the atlas articulates with the axis

What is the function of the superior articulating facet of a vertebra? 1. to articulate with the inferior facet of the vertebra below it 2. to articulate with the inferior facet of the vertebra above it 3. to articulate with the superior facet of the vertebra above it 4. to articulate with the ribs

2. to articulate with the inferior facet of the vertebra above it

the fibula is not a weight bearing bone and if broken, you can still walk on your leg but it will be painful. 1. true 2. false

2. true

Ribs 1-7 attach anteriorly to the sternum are called what type of ribs? 1. floating ribs 2. true ribs 3. false ribs

2. true ribs

Pick the description that best fits the term "spine" as in the anterior superior iliac spine. 1. an elevation or projection 2. a narrow ridge of bone 3. a sharp, pointed, narrow process 4. a small pit or depression 5. a rough projection of bone for attachment of muscles 6. a small, rounded projection 7. a shallow, broad or elongated pit

3. a sharp, pointed, narrow process

Pick the description that best fits the term "fovea" as in the fovea of the head. 1. a shallow, broad or elongated pit 2. an elevation or projection 3. a small pit or depression 4. a narrow ridge of bone 5. a rough projection of bone for attachment of muscle 6. a sharp, pointed, narrow process 7. a small, rounded projection

3. a small pit or depression

Pick the description that best fits the term "eminence" as in the intercondylar eminence. 1. a shallow, broad or elongated pit 2. a small, rounded projection 3. an elevation or projection 4. a narrow ridge of bone 5. a sharp, pointed, narrow process 6. a small pit or depression 7. a rough projection of bone for attachment of muscles

3. an elevation or projection

in a joint, cartilage fills the space between bones resulting in not much movement such as with breastbone (sternum) and some ribs 1. synovial 2. fibrous 3. cartilaginous

3. cartilaginous

This bone is a single bone in the midline of the cranium and contains air cells and the cribiform plate. 1. sphenoid 2. temporal (tympanic part) 3. ethmoid 4. occipital 5. frontal

3. ethmoid

joints form the soft spots on a baby's head. 1. synovial 2. cartilaginous 3. fibrous

3. fibrous

What bone forms the bump or lateral malleolus located on the lateral side of the ankle? 1. talus 2. calcaneus 3. fibula 4. tibia

3. fibula

Which thin muscle of the posterior forearm forms into four thin tendons distally with an origin on the common flexor tendon, insertion on middle phalanges 2 - 5 and action of flexing fingers 2 - 5? 1. pronator teres 2. brachioradialis 3. flexor digitorum superficialis 4. flexor digitorum profundus 5. flexor pollicis longus

3. flexor digitorum superficialis

Choose from the options below the correct order for the stages of intramembranous ossification. 1. calcification of the osteoid matrix, formation of trabeculae, development of the periosteum, formation of an ossification center 2. development of the periosteum, formation of an ossification center, calcification of the osteoid matrix, formation of trabeculae 3. formation of an ossification center, calcification of the osteoid matrix, formation of trabeculae, development of the periosteum 4. formation of trabeculae, development of the periosteum, formation of an ossification center, calcification of the osteoid matrix

3. formation of an ossification center, calcification of the osteoid matrix, formation of trabeculae, development of the periosteum

what anatomic feature on the scapula is the site of articulation with the head of the humerus? 1. olecranon fossa 2. acromion 3. glenoid fossa 4. trochlear notch 5. medial epicondyle

3. glenoid fossa

In the final stage of endochondral ossification, the epiphyseal plate is formed from which one of the following types of cartilage? 1. elastic cartilage 2. fibrocartilage 3. hyaline cartilage

3. hyaline cartilage

The bones of synchondroses are connected by a layer of which one of the following types of cartilage? 1. elastic cartilage 2. fibrocartilage 3. hyaline cartilage

3. hyaline cartilage

In movements possible around a synovial joint, __________ describes the movement in which two bones are widened to an angle greater than the normal amount. 1. abduction 2. flexion 3. hyperextension 4. extension 5. adduction 6. circumduction

3. hyperextension

Which bone below contains the nasolacrimal duct and forms the anterior part of the medial wall of the orbit. 1. palatine 2. nasal 3. lacrimal 4. zygomatic 5. maxilla 6. hyoid 7. mandible

3. lacrimal

At the femur's most distal end, what bump can you palpate on the lateral surface of the femur at the knee joint? 1. greater trochanter 2. lesser trochanter 3. lateral condyle 4. medial condyle 5. lateral epicondyle

3. lateral condyle

Which part of the sternum is most superior portion and site of articulation with the first and second costal cartilages? 1. diploid process 2. body 3. manubrium

3. manubrium

What portion of the hip do we sit on and is the site for muscle attachment? 1. acetabulum 2. iliac crest 3. obturator foramen 4. ischial tuberosity 5. anterior superior iliac crest

3. obturator foramen 4. ischial tuberosity

An immature bone cell found in growing bone is called what? 1. lacunae 2. osteocyte 3. osteoblast 4. osteoclast 5. osteon

3. osteoblast

what feature is only found on cervical vertebra? 1. presence of articulation facets 2. presence of a vertebral body 3. presence of transverse foramen 4. presence of vertebral spine

3. presence of transverse foramen

Which movement about a synovial joint describes the movement of the scapula forward? 1. pronation 2. adduction 3. protraction 4. retraction 5. abduction 6. supination

3. protraction

When describing a muscle, which one of the following words best describes the Latin word "brevis"? 1. huge 2. largest 3. short 4. smallest 5. long

3. short

Which one of the following joints allows the widest range of movement in the body? 1. knee 2. elbow 3. shoulder 4. temporomandibular 5. hip

3. shoulder

Which one of the following best describes a motor unit? 1. a single muscle group and its innervating nerves 2. l the myofilaments in a muscle fiber 3. somatic motor neuron and all the muscle fibers it innervates 4. a single muscle fiber 5. an antagonistic pair of muscles

3. somatic motor neuron and all the muscle fibers it innervates

Which one of the following muscles does not insert on the hyoid bone? 1. sternohyoid 2. digastric 3. sternothyroid 4. omohyoid 5. thyrohyoid

3. sternothyroid

During muscle contraction, when calcium ions bind to ___________, the binding site on the actin filament is uncovered. 1. myosin 2. tropmoyosin 3. troponin 4. cross bridges

3. troponin

Pick the description that best fits the term "crest" as in the iliac crest 1. a small pit or depression 2. a small, rounded projection 3. a sharp, pointed, narrow process 4. a narrow ridge of bone 5. an elevation or projection 6. a shallow, broad or elongated pit 7. a rough projection of bone for attachment of muscles

4. a narrow ridge of bone

pick the description that best fits the term "fossa" as in the iliac fossa. 1. a rough projection of bone for attachment of muscle 2. a small pit or depression 3. an elevation or projection 4. a shallow, broad or elongated pit 5. a sharp, pointed, narrow process 6. a narrow ridge of bone 7. a small, rounded projection

4. a shallow, broad or elongated pit

In movements possible around a synovial joint, __________ describes the movement of an arm or leg being moved away from the body. 1. circumduction 2. adduction 3. extension 4. abduction 5. flexion 6. hyperextension

4. abduction

Which of the hamstring muscles below have an origin on the ischial tuberosity? 1. semitendinosus 2. biceps femoris 3. semimembranosus 4. all do 5. none do

4. all do

Which of the following best describes cardiomyocytes? 1. tire easily, branched 2. tire easily, lack nuclei 3. lack nuclei, branched, linked by intercalated discs 4. branched, linked by intercalated discs, striated

4. branched, linked by intercalated discs, striated

In movements possible around a synovial joint, __________ describes the movement of an arm in as wide a circle as possible 1. abduction 2. adduction 3. hyperextension 4. circumduction 5. flexion 6. extension

4. circumduction

The medullary cavity is a feature of which one of the following regions of a long bone? 1. periosteum 2. epiphysis 3. metaphysis 4. diaphysis

4. diaphysis

The muscles of the back can be divided into which three of the following categories? 1. multifidus, erector spinae, superficial muscles 2. multifidus, iliocostalis cervicis, transversospinalis 3. erector spinae, iliocostalis cervicis, multifidus 4. erector spinae, transversospinalis, superficial muscles

4. erector spinae, transversospinalis, superficial muscles

Which of the following structures pass through openings in the diaphragm? 1. heart, esophagus, aorta 2. liver, esophagus, aorta 3. esophagus, aorta, superior vena cava 4. esophagus, aorta, inferior vena cava 5. superior vena cava, heart, liver

4. esophagus, aorta, inferior vena cava

Which one of the following terms best describes a muscle that holds the proximal end of another muscle in place? 1. antagonist 2. agonist 3. synergist 4. fixator 5. prime mover

4. fixator

In movements possible around a synovial joint, __________ describes the movement of bringing two bones closer together 1. hyperextension 2. adduction 3. circumduction 4. flexion 5. abduction 6. extension

4. flexion

What is the insertion of the gluteus medius? 1. lesser trochanter of femur 2. tibial tuberosity 3. acetabulum 4. greater trochanter of femur 5. gluteal tuberosity

4. greater trochanter of femur

Which suture is responsible for holding together the occipital and parietal bones of the cranium? 1. sagittal suture 2. coronal suture 3. pterion 4. lambdoid suture 5. asterion

4. lambdoid suture

Which one of the following names is given to the longitudinal ridge on the posterior aspect of the femoral shaft that provides an origin point for a number of muscles, including the biceps femoris, adductor magnus and vastus lateralis? 1. greater trochanter 2. intertrochanteric crest 3. intercondylar fossa 4. linea aspera

4. linea aspera

which bone listed below contains the site for teeth attachment, forms most of the hard palate and contains the largest sinuses in our skull? 1. palatine 2. nasal 3. mandible 4. maxilla 5. lacrimal 6. hyoid 7. zygomatic

4. maxilla

what anatomic feature of the humerus is known as the "funny bone"? 1. deltoid tuberosity 2. lateral epicondyle 3. lesser tubercle 4. medial epicondyle 5. greater tubercle

4. medial epicondyle

In intramembranous ossification during the formation of an ossification center, the mesenchyme cells differentiate initially into which one of the following bone cells? 1. osteoblasts 2. osteoclasts 3. osteocytes 4. osteogenic cells

4. osteogenic cells

which carpal bone can be palpated in the region known as the anatomic snuff box? 1. lunate 2. capitate 3. triquetral 4. scaphoid 5. trapezium

4. scaphoid

What is the origin for the internal intercostals? 1. superior borders of ribs 1 - 11 2. inferior borders of ribs and costal cartilages 1 - 11 3. inferior borders of ribs 1 - 11 4. superior borders of ribs 2 - 12 5. internal aspect of ribs 1 - 11

4. superior borders of ribs 2 - 12

The space between the end of a motor neuron and where it abuts against the muscle cell membrane is called what? 1. cross bridge 2. axon 3. Z-line 4. synapse

4. synapse

Which terms below best describe the joints that permit free movements? 1. fibrous and synarthroses 2. fibrous and diarthroses 3. cartilaginous and amphiarthroses 4. synovial and diarthroses 5. synovial and synarthroses

4. synovial and diarthroses

In order to regulate the levels of calcium in the blood, which one of the following hormones is secreted by the thyroid gland and opposes the effects of parathyroid hormones by reducing osteoclastic activity in bone? 1. insulin-like growth hormone 2. thyroid hormone T3 3. human growth hormone 4. calcitriol 5. calcitonin

5. calcitonin

Which one of the following neurotransmitters is released by somatic motor neurons where they synapse with skeletal fibers? 1. glutamate 2. serotonin 3. dopamine 4. norepinephron 5. acetylcholine

5. acetylcholine

pick the term below that best fits what a meatus is. 1. a cavity or recess in a bone 2. a round hole through a bone 3. a slit through a bone 4. a bony groove that houses a tendon, nerve or blood vessel 5. an opening of a canal through a bone

5. an opening of a canal through a bone

what anatomic feature on the hip bone is injured when one has a hip pointer? 1. obturator foramen 2. acetabulum 3. ischial tuberosity 4. lateral condyle 5. anterior superior iliac crest 6. medial malleolus

5. anterior superior iliac crest

Identify the large muscle on front of the arm with two heads that have an origin on the scapula and insertion on the radial tuberosity. 1. triceps brachii 2. brachialis 3. pectorals major 4. latissimus dorsi 5. biceps brachii

5. biceps brachii

Choose the action of the orbicularis oris muscle. 1. closes eye as in winking 2. raises the upper lip as in smiling 3. raises the upper eyelid 4. keeps food from collecting between teeth and cheeks 5. closing and pursing the lips

5. closing and pursing the lips

Which one of the following muscle groups acts to increase the size of the throrax by drawing the ribs upwards and outwards? 1. diaphragm 2. innermost intercostals 3. transversus abdominis 4. internal intercostals 5. external intercostals

5. external intercostals

Which muscle below forms the bulk of the calf musculature, originates on the medial and lateral condyle of the femur and inserts on the calcaneus. 1. flexor digitorum longus 2. soleus 3. flexor halluncis longus 4. popliteus 5. gastrocnemius

5. gastrocnemius

Synovial fluid in a synovial joint is composed primarily of what? 1. saline 2. plasma 3. glycolipids 4. interstitial fluid 5. hyaluronic acid

5. hyaluronic acid

What is the name of the muscle that surrounds the eye and is used to close the eye tightly to keep out a foreign object? 1. orbicularis fris 2. levator palpebrae superioris 3. buccinators 4. zygomatic minor 5. orbicularis oculi

5. orbicularis oculi

Which thin muscle crosses the front of the elbow with an origin on the humerus and coronoid process of ulna, insertion on radius and action to flex elbow and pronate forearm? 1. flexor pollicis longus 2. flexor digitorum superficialis 3. brachioradialis 4. flexor digitorum profundus 5. pronator teres

5. pronator teres

What is the origin of the rectus abdominis muscle in the trunk musculature? 1. manubrium of sternum 2. ribs 5 - 12 3. costal cartilages 9 - 12 4. xiphoid process of sternum and costal cartilages 5. pubis of hip bone

5. pubis of hip bone

Which of the muscles listed below is located between the ribs and scapula and functions to protract the scapula and pectoral girdle? 1. trapezius 2. triceps brachii 3. pectoralis minor 4. biceps brachii 5. serrates anterior

5. serrates anterior

Choose the insertion of the levator palpebrae superioris muscle. 1. temporal bone 2. lesser wing of sphenoid 3. zygomatic bone 4. modiolus 5. superior tarsus (eyelid)

5. superior tarsus (eyelid)

pick the description that best fits the term "tubercle" as in the lesser tubercle of the humerus 1. a narrow ridge of bone 2. a sharp, pointed, narrow process 3. an elevation or projection 4. a shallow, broad or elongated pit 5. a small pit or depression 6. a small, rounded projection 7. a rough projection of bone for attachment of muscle

6. a small, rounded projection

Which movement about a synovial joint describes the movement of rotating the forearm so that the palms face upwards or in the anterior direction? 1. retraction 2. protraction 3. adduction 4. abduction 5. pronation 6. supination

6. supination

which bone below forms the inferior and lateral walls of the orbits? 1. lacrimal 2. maxilla 3. nasal 4. hyoid 5. palatine 6. zygomatic 7. mandible

6. zygomatic

pick the description that best fits the term "tuberosity" as in the ischial tuberosity. 1. an elevation or projection 2. a sharp, pointed, narrow process 3. a shallow, broad or elongated pit 4. a small, rounded projection 5. a small pit or depression 6. a narrow ridge of bone 7. a rough projection of bone for attachment of muscle

7. a rough projection of bone for attachment of muscle

Classification of Skeletal Muscles

Fascicular Arrangement of Skeletal Muscles There are five categories of skeletal muscles that can be classified according to their fasciculararrangement. 1. Fusiform muscles - formed by a central muscle belly that converges at one or both ends into a tendon. Fusiform muscles can have one head at each end like the extensor carpi radialis longus. 2-headed muscle - fusiform muscle with two tendons that merge and insert into one like the biceps brachii. 3-headed muscle - a fusiform muscle with three tendons that merge and insert as one like the triceps brachii. 2. Parallel muscles - muscle fibers lie parallel to each other and form flat, straight, quadrateand 2-bellied muscles. Flat muscle - a parallel muscle that forms a sheet of fibers such as the transversusabdominis. Straight muscle - long and strap-like and may be interrupted by tendinous intersection such as the rectus abdominis. Quadratus muscle - composed of short fibers such as the pronator quadratus. 2-bellied muscle - muscle interrupted by a tendinous intersection such as the omohyoid. 3. Pennate muscles - muscle fibers are attached obliquely to a central tendon like the barbs of a feather. Unipennate muscle - has a central tendon to which fibers converge on both sides such as the rectus femoris. Multipennate muscle - has several tendons toward which muscle fibers converge such as the deltoid. 4. Orbicular muscles - sphincter-like sheet of muscle encircling an oriface such as the mouth or palpebral fissures. Example is the orbicularis oculi. 5. Convergent muscles - also known as triangular muscles, fibers originate from large area but converge onto one attachment point such as the temporalis.

CRANIAL BONES

Frontal Bone: from the coronal suture to the roof of the orbits with superciliary arch (curved ridge above the eyebrows). Frontal sinus (mucous membrane lined space) is above the nasal part of frontal bone. Occipital bone: forms back and base of skull and contains foramen magnum, large hole through which spinal cord leaves cranial cavity. You can feel the external occipital protuberance as a lump on the back of the skull which is the attachments site for the nuchal ligament. On the lateral part of the occipital bone are the occipital condyles which are the sites fro articulation with the superior facet of the atlas, the first cervical vertebra. Temporal bone: Squamous part - has zygomatic process for articulation with the zygomatic bone. Also has mandibular fossa for articulation with mandibular condyle. Temporal Bone: Tympanic part - external acoustic meatus is circular opening into auditory canal. Styloid process - narrow downward projection which serves as a site of attachment of the stylomandibular ligament stylohyoid and two other muscles. Temporal Bone: Mastoid Process - large prominence located behind external acoustic meatus and is the insertion point for the sternocleidomastoid muscle. Temporal Bone: Petrous part - has the Internal acoustic meatus in the posterior region for the vestibulocochlear nerve to go from the internal ear to the brain. Inside the petrous part, the inner ear contains the three bones known as ossicles, the malleus, incus and stapes for the transmission of sound from the tympanic membrane to the cochlea. Ethmoid Bone: single bone in midline containing air cells forming sinus-like cells draining int the nasal cavity and the cribiform plate which has many holes (olfactory foramina) for the olfactory nerves to carry sense of smell signals from nose epithelium to the olfactory bulbs in brain. Sphenoid: located at base of skull and shaped like a butterfly. Has many openings for nerves such as ophthalmic, oculomotor, trochlear and abducens nerves to reach the brain. The pituitary fossa is a deep pit on the superior surface and is shaped like a saddle for the pituitary to fit into and be protected.

Characteristics of Bone

Let's focus first on the basic bone functions and bone structure. A primary function of bones is to form a framework for muscle attachment but bones also serve as organs and perform the following functions: Movement- with muscles attached to them, bones assist in maintaining or changing position of body parts. Protection- provide hard exterior compartment to house organs such as brain, lungs, heart and other organs. Support- bones support muscles and provide an attachment site for muscles Mineral Storage - bones serve as sites for storage of Calcium and Phosphate which can be released when body fluids require them. Blood Cell Formation- Some bones with spongy interiors serve as sites for blood cell formation. Bones vary in size from tiny ear bones to large femurs which make up the thigh bones. Bone shape can be categorized as (a) long , (b) short or cube-shaped and (c) irregular. Bones are organs in that they have all four basic tissue types in them, i.e, epithelium, connective tissue, muscle and nervous tissues. Bone is a living structure. Bone cells called osteocytes maintain structure of living bone in small compartments called lacunae. Terms to be familiar with from are: osteocyte - mature bone cell found in fully formed bone. They maintain bone and replace what is lost osteoblast - immature bone cell found in growing bone. They secrete bone matrix and can be found in areas of new bone formation. osteoclasts - are giant cells with up to 15 - 20 nuclei per cell. They function in bone resorption, i.e., shaping bone by resorbing bone in some areas. lacunae - small round spaces which house osteocytes compact bone - located in the shaft of long bones and appears solid but under the microscope has many lacunae with osteocytes in them as well as blood vessels to nourish the cells Haversian System (osteon) - the combination of a Haversian Canal, concentric lamellae(rings around canal) and osteocytes, Haversian Canal - space for blood vessel which brings nutrient to bone cells and takes waste products away Spongy Bone Tissue - found in the head of long bones and in the flat bones of the skull, contain red bone marrow and participate in red blood cell production red bone marrow - bone marrow in active formation of red blood cells and some types of white blood cells yellow bone marrow - bone marrow that has stopped producing blood cells and now is filled with fat tissue to give it a yellow color. How do long bones grow? First, a cartilage model of the bone is formed and then a bony collar forms around the future shaft area. Then blood vessels migrate into shaft area through boney collar and eventually two more areas of ossification occur at either end. An epiphyseal plate of cartilage forms at either end and is the future growth plate so bone may grow longer.

FACIAL BONES

Maxilla - paired bones forming much of the skeleton on the upper face and serve as site of support for teeth attachment. The palatine process extends horizontally to form most of the hard palate (what you can feel when you raise your tongue to touch the roof of the mouth cavity). It contains the maxillary sinus, the largest of the sinuses in our skull. Zygomatic Bone: forms the cheeks of the inferior and lateral walls of the orbit. Palatine Bone: forms part of palate at back of roof of mouth and also forms the floor of the orbit. Lacrimal Bone: paired bones which lie in the anterior part of the medial wall of orbit and contain the groove for the nasolacrimal duct known as the nasolacrimal canal. Fossa for lacrimal sac is a depression on lacrimal bone which collects tears from the eyes and empties into the nasal cavity. Nasal Bone: single bone that forms the upper part of the bridge of the nose. Inferior Nasal Concha: form lateral wall of nasal cavity and covered with mucous membrane. Vomer: flat bone forming lower part of nasal septum Mandible: largest movable bone in skull which forms the lower jaw with attachment of teeth. The coronoid process at the posterior portion is the site for attachment of the temporalis muscle which is what bulges out on the side of your jaw when your mouth is tightly clenched. Hyoid Bone: is a horseshoe-shaped bone located just superior to the larynx. It is the only bone that does not articulate with any other bone in the body and serves as the attachment site for muscles of tongue, pharynx and neck

Skeletal Muscle Contraction

Muscles generate ATP in three ways: from creatine phosphate, anaerobic respiration and aerobic respiration. Creatine phosphate - creatine kinase transfers a phosphate from creatine phosphate to ADP making ATP. One ATP molecule is made from one molecule of creatine phosphate. There's usually enough creatine phosphate to supply for ATP for a sustained contraction of about 15 seconds so this type of energy source is used during short bursts of vigorous activity. The reverse process is used during muscle relaxation to make creatine phosphate. Anaerobic respiration - used when energy need of muscle is high and oxygen supply is low. Glucose produces ATP with production of pyruvic acid and then lactic acid which when it accumulates can eventually cause muscle cramping. Two molecules of ATP produced per glucose molecule through glycolysis. Aerobic cellular respiration - occurs when energy needs by muscle are not high and oxygenated myoglobin levels are high and muscle activity is low. Aerobic respiration releases 36 ATP molecules per glucose molecule but as soon as continued contraction occurs and oxygen levels and oxygenated myoglobin levels decrease, then respiration switches over to anaerobic. Muscle Fatigue - inability of muscle to maintain force of contraction caused by prolonged contraction and depletion of ATP, creatine phosphate, glycogen stores and oxygen with accumulation of ADP and lactic acid and a drop in muscle pH. Oxygen debt - increased muscle contraction builds up lactic acid and it takes time to replace ATP levels and remove lactic acid and the amount of oxygen necessary to do that is considered the oxygen debt.

MUSCLES OF THE HEAD

Muscles of Facial Expression - muscles that anchor skin to the skull and mandible and when contracted cause changes in facial expression. Scalp and Forehead: Occipitofrontalis: has two parts, one on forehead and the other on the back of the head which are joined together by an aponeurosis (broad sheet of fibrous tissue located on top of the head). Frontal belly of occipitofrontalis has its origin on the Galea aponeurotica, insertion on the skin of the forehead and its action is to raise the eyebrows and wrinkles the forehead. The occipital belly has its origin on the superior nuchal line of the occipitall bone, inserts of the Galea aponeurotica with an action of retracting the scalp (drawing it backwards). Ocular Region: Levator palpebrae superioris: thin muscle within upper eyelid and is the antagonist of the orbicularis oculi. Its origin is the lesser wing of the sphenoid, inserts on the superior tarsus (upper eyelid) and has an action of raising the upper eyelid. Orbicularis oculi: flat, circular muscle that surrounds the eye. It's origin is on the nasal part of frontal bone, frontal process and lacrimal bone with an insertion on the skin of the eyelid and action of closing the eye when you wink or squeeze your eyelid tight to keep out a foreign object. Oral Region: Orbicularis oris: circular muscle surrounding the mouth and lips with an origin on the Modiolus(concentration of fibrous tissue in cheek area for muscle attachment), insertion on the skin of the lips and action of closing and pursing the lips as after sucking on a lemon. Buccinator: sheet of muscle within the cheek with an origin on the maxilla and mandible, insertion on the Modiolus and action of compressing the cheek as in blowing up a balloon. It also aids in chewing by keeping the food from piling up between your teeth and cheeks. Zygomaticus minor: long, thin muscle of the cheek with an origin on the Zygomatic bone, insertion on the Oribularis oris and an action of raising the upper lip allowing us to smile and laugh. Platysma: Thin, flat, superficial muscle of the anterior neck with an origin on the superficial fascia of the thorax, insertion on the Mandible and Modiolus and action of wrinkling the skin of the neck which makes the Platysma the antagonist for the Zygomatic muscle You do not have to know this muscle but I am interested in knowing if you have Auricular muscles which have an action of wiggling the ears. I have them but not all people do. Many animals such as horses have them and are responsible for the twitching movement of their ears. If you can wiggle your ears, please let me know as I am curious as to how many people have auricular muscles.

How Skeletal Muscles and Bones Interact

Skeletal muscles attach to bones at two sites which are referred to as the origin and insertion. Definition of Origin - during contraction, this end of the muscle stays relatively motionless. Definition of Insertion - during contraction, this end moves the most. Rule of thumb - the muscle insertion moves toward the origin Many muscles operate together to produce the same movement and are termed synergists while others work in the opposite direction and are termed antagonists. Example - biceps brachii (anterior portion of upper arm) can effect flexion of forearm onto upper arm. Triceps brachii (posterior region of upper arm) can effect extension by straightening forearm away from upper arm. Origin of biceps - scapula, insertion of biceps - radiusOrigin of triceps - scapula, insertion of triceps - ulna

SOME EXTENSORS OF THE WRIST AND HAND

We will look at only a few of the forearm extensors but all the extensor tendons travel beneath the extensor retinaculum which holds the extensor tendons in place when muscle contraction occurs. The primary action is to extend the elbow joint but do participate in supination of the forearm and abdunction/adduction of the hand. Superficial Extensors: Anconeus - small triangular muscle on lateral side of elbow with origin on the lateral epicondyle of humerus, insertion on olecranon of ulna and action of extending the elbow. Extensor digitorum - thin muscle of anterior forearm that divides into four thin tendons digitally which have an origin on the common extensot tendon and insertion on fingers 2 - 5 and an action of extending the wrist and finger 2 - 5. Deep Flexors: Brachioradialis - thin muscle located on the front of the forearm with origin on humerus, insertion on styloid process of radius and flexes the elbow. Pronator quadratus - small square muscle that lies on the anterior distal forearm with origin on ulna, insertion on radius and action to pronate the forearm. Flexor digitorum profundus - thin muscle of the posterior forearm that divides into four thin tendons distally with origin on ulna, insertion on phalanges 2 - 5 with an action to flex the wrist and fingers 2 - 5. Flexor pollicis longus - thin muscle of the posterior forearm and thumb with origin on the ulna, insertion on the 1st distal phalanx and action to flex the thumb. Superficial Flexors: Pronator teres - thin muscle that crosse the front of the elbow with origin on humerus and coronoidprocess of ulna, insertion on radius and action to flex elbow and pronate forearm Flexor digitorum superficialis - thin muscle of posterior forearm into four thin tendons distally with origin on common flexor tendon, insertion on middle phalanges 2 - 5 and action of flexes fingers 2 - 5.

Control of Contraction

What happens when a motor neuron stimulates a muscle to contract? (See Excitation-Contraction Coupling topic in Physiology section of online A & P text. An electrical signal termed an action potential or impulse speeds down the axon to the muscle fibers. At the neuromuscular junction (myoneural junction), the nerve endings release acetylcholine(Ach) into the space between the nerve ending and muscle fiber known as the synapse. The Ach begins the electrical impulse that spreads over the muscle fiber and causes the sarcoplasmic reticulum (smooth ER) in the muscle fiber to release Calcium ions. The Calcium ions bind to troponin molecules on the actin filament, it changes the conformation (shape) of actin filaments allowing myosin cross bridges to bind to actin. When electrical stimulation stops, energy from ATP is used to pump Calcium back into sarcoplasmic reticulum allowing troponin and tropomyosin to rebind with myosin stopping contraction and allowing the actin filaments to slide back to the relaxed position in the sarcomere.

Twitch Contractions

What is a twitch contraction? A twitch contraction is a fast, brief contraction of a muscle following a single stimulus and the recording of that twitch is called a myogram. Latent period - time that passes between stimulation of the muscle and contraction of that muscle (we're talking now about a muscle, not a muscle fiber.) During the latent period, the action potential caused by the stimulus is spreading over the myofiber sarcolemma causing Calcium to be released by the sarcoplasmic reticulum. This period lasts around 2 msec. Contraction period - during this period, crossbridge formation occurs due to buildup of Calcium ion concentration and sarcomere length is decreasing (undergoing contraction), muscle tension rises and this period lasts about 15 msec. Relaxation period - once peak tension has occurred and stimulation stops, calcium ions are taken back up into sarcoplasmic reticulum with coverage of myosin head binding sites. This causes detachment of crossbridges and reduction in muscle tension. This period lasts about 25 msec. Skeletal muscle fibers contract either slowly and are called "slow twitch fibers" or fast and are called "fast twitch fibers". Their speed is dependent upon how fast ATPase in the myosin heads can hydrolyze ATP. Slow twitch fibersThese fibers regenerate ATP mainly via aerobic respiration which is slow but have many large mitochondria and high levels of myoglobin which gives these muscles a red color. The high levels of mitochondrial enzymes provides them with a sustained mechanism by which they use energy and makes them fatigue resistant. Slow twitch fibers are found in large muscles such as the gluteals. Fast twitch fibers - generate ATP at a faster pace than slow twitch fibers. Their sarcoplasmicreticulum also releases and takes up calcium ions faster. They also hydrolyze ATP faster and rely upon anaerobic respiration to generate short term energy transfer for contraction. Fast twitch fibers develop tension 2-3 times the rate of slow twitch fibers but do tire more quickly because of that. An example of fast twitch fibers can be found in the intrinsic muscles of the eye. Frequency of Stimulation (see Contraction information in Skeletal Muscle unit of online A & P text) - When a muscle (such as in an isolated frog gastrocnemius muscle) is stimulated at different frequencies, the following types of myograms can be seen. Summation - wave summation is seen when the stimuli are delivered to a muscle fiber in quick succession which causes an increase in force of contraction. Incomplete tetanus - incomplete tetanus occurs when muscle stimulation occurs soon after the absolute refractory period (time when a following sequence causes no effect) but before the muscle can completely relax. The tension in the muscle gradually increases to its maximum. Complete tetanus - complete or fused tetanus occurs when sustained contraction happens with no chance for relaxation. Complete tetanus happens when a fiber is stimulated over 90 times a second. Complete tetanus is primarily a laboratory phenomenon and rarely happens in vivo.