Anatomy: Exam 2

Describe fibrous joints and give examples of them. What kind of tissue is present?

Characteristics: No joint cavity, bones held by dense connective tissue

Ex: Synarthrosis (sutures), syndesmosis (interosseous membrane), gomphosis (teeth)

Describe cartilaginous joints and give examples of them.

Characteristics: no joint cavity, bones joined by cartilage

Ex: symphysis (pubic symphysis & intervertebral discs), rib to sternum (synchondrosis)

Describe synovial joints and give examples of them.

Characteristics: fluid-filled cavity (unlike the others), enclosed within connective tissue, bones are attached by ligaments

Ex: elbow, knee, etc.

Describe synarthrosis, amphiarthrosis, and diarthrosis. Give examples of each.

Synarthrosis- immobile joint, fibrous or cartilaginous

• Ex: tooth to jaw, rib to sternum

Amphiarthrosis- slightly mobile, fibrous or cartilaginous

• Ex: tibia to fibula articulation (interosseous membrane)

Diarthrosis- FREELY mobile, ALL synovial joints

• Ex: knee joint, elbow joint, etc.

Where is synovial fluid secreted from? What is the function of synovial fluid?

The fluid is secreted from the synovial membrane

Fluid acts as a shock absorber & decreases friction

List the accessory parts of a joint.

Fat- common in the back of the knee (popliteal area)

Menisci- made of fibrous cartilage

Ligaments- examples of ACL & PCL

Bursae- between ligaments & tendons

Tendons- attach muscle to bone

Describe the function of bursae

Synovial fluid-filled saclike structures that minimize friction at joints

What is the function of the tendon sheath?

Surrounds a tendon to protect it from friction

What is the difference between ligaments and tendons?

Ligaments- connect bone to bone for stability

Tendons- connects muscle to bone for movement

Describe the function of menisci.

Pads of dense fibrocartilage

Allows bones of different shapes to fit together tightly

What is the part of intervertebral disc that pulps out in a herniated disc?

Nucleus pulposus

What is a bunion?

Swelling of metatarsophalangeal (MTP) joint

Sprain vs. strain

Sprain- tear in a ligament

Strain- overstretching of a ligament

Subluxation vs. full luxation

Subluxation- partial dislocation

Full luxation- full dislocation

Why is the “ball” part of the artificial joint in a hip replacement rough?

It is rough because it allows bone to grow into it and cement it in place

Osteoarthritis (OA) vs. rheumatoid arthritis

Osteoarthritis- degenerative joint disease where cartilage is lost (linked to age)

Rheumatoid arthritis- autoimmune disease where immune system attacks joints

What are characteristics and function of muscle?

Characteristics: contractile, excitable, elastic

Functions: movement, support, storage, & thermogenesis

What are basket cells (myoepithelial cells)?

They secrete proteins that have an anti-cancer effect

What are characteristics of skeletal muscle?

Voluntary, striated, multi-nucleated, lots of mitochondria, very vascular, amitotic (does NOT divide)

How can you increase muscle mass if muscle fibers are amitotic?

When there are tears, your muscle fibers (muscle cells) grow larger

This is partially due to satellite cells which are stem cells

Superficial fascia vs. deep fascia

Superficial fascia- provides insulation, attaches skin to muscle

Deep fascia- partitions muscles into groups; connects ligaments, tendons, etc.

Describe the 3 layers of fascia, and what kind of tissue is in each.

1) Epimysium- surrounds entire group of muscle fascicles

• Tough fibrous connective tissue

2) Perimysium- provides pathway for blood vessels & nerves

• Areolar connective tissue

3) Endomysium- surrounds each individual muscle fiber

• Areolar connective tissue

What are myofibrils and where are they found?

Myofibrils consist of actin & myosin

Found in sarcoplasm (cytoplasm of muscle cells)

Describe sarcoplasmic reticulum and its function.

Fluid-filled system of sacs that surround each myofibril

Stores and releases calcium

Describe T-tubules and its function.

Invaginations of sarcolemma that help propagate action potentials

Describe terminal cisterns and its function.

Part of sarcoplasmic reticulum & align with T tubules to form triad

Release calcium to trigger muscle contractions

What forms the triad?

Transverse tubules (t-tubules) & two terminal cisternae on either side of it

Describe a sarcomere.

• Measured from Z disc to Z disc

• Site of muscle contraction

Where do the striations in muscle come from?

Actin & myosin

What are the contractile, regulatory, & structural proteins?

1) Contractile- myosin & actin

2) Regulatory- troponin & tropomyosin

3) Structural- titin, myomesin, nebulin, & dystrophin

• Structural proteins provide alignment, elasticity, etc.

Describe the function of dystrophin, myomesin, titin, & nebulin.

Myomesin- protein that creates anchoring site for myosin

Dystrophin- keeps actin filaments aligned with sarcolemma

Titin- provides ability to be elastic

Nebulin- stiffens actin

Which band or zone is not visible under the microscope? What is the A band composed of?

H zone is NOT present in the microscope view

The A band consists of the overlap of actin & myosin

Describe flexion & extension.

Flexion- decrease angle between bones

Extension- increases angle between bones

Describe lateral flexion.

Flexion in a frontal plane usually involving the head or trunk

Abduction vs. adduction

Abduction- moving a body part away from the body

Adduction- moving a body part towards midline

Define circumduction, supination, & pronation.

Circumduction- when distal end of body part makes a circle

Supination- movement where palms are anterior

Pronation- palms are posterior

Define inversion, eversion, dorsiflexion, & plantar flexion.

Inversion- sole of foot faces medially

Eversion- sole of foot faces laterally

Dorsiflexion- dorsum of foot moves up towards tibia

Plantar flexion- sole of foot moves posteriorly

Elevation vs. depression

Elevation- upward movement

Depression- downward movement

Origin vs. insertion of muscle

Origin- stationary position

Insertion- movable end 

What layer of fascia arranges muscle?

Perimysium creates compartmentalization of muscle

Arrangement determines range, muscle power, & speed

What is the origin and insertion for muscles of facial expression?

Origin: fascia or bones

Insertion: skin

Describe the function of the genioglossus & geniohyoid.

Genioglossus- allows you to stick out & roll your tongue

Geniohyoid- depresses the mandible

What are the functions of the suprahyoid & infrahyoid?

Functions to stabilize hyoid bone for tongue movement

Which muscle is considered a “white zone”? Explain why.

Linea alba is considered a “white zone” because there’s no blood supply nor nerve tissue

What is the function of the muscles in the anterior abdominal wall?

Contains viscera (organs), compresses cavity, flexes, & rotates column

Why is it easy for males to get an inguinal hernia?

Inguinal canal allows passage of spermatic cord, blood supply, & nerve

Bowel can poke through this canal and cause an inguinal hernia

Which three muscles form the inguinal canal?

External oblique, internal oblique, & transversus

Frontalis (function, origin & insertion)

Function: elevates eyebrows

Origin: epicranial aponeurosis

Insertion: skin of eyebrows

Orbicularis oris (function, origin & insertion)

Function: closes, protrudes lips

Origin: fibers surrounding mouth

Insertion: skin of lips

Orbicularis oculi (function, origin & insertion)

Function: closes eye, squint

Origin: frontal & maxillary bones

Insertion: tissue of eyelid

Platysma (function, origin & insertion)

Function: depress mouth corners

Origin: fascia of chest

Insertion: lower margin of mandible

Buccinator (function, origin & insertion)

Function: compress (pull in) cheek

Origin: maxilla and mandible

Insertion: orbicularis oris

Zygomaticus (function, origin, & insertion)

Function: extends mouth corners (into a smile)

Origin: zygomatic bone

Insertion: skin at angle of mouth

Risorius (function, origin & insertion)

Function: retracts mouth corners

Origin: fascia of masseter

Insertion: skin at angle of mouth

Masseter (function, origin, & insertion)

Function: elevates mandible (closes jaw)

Origin: zygomatic bone
Insertion: angle of mandible

Temporalis (function, origin & insertion)

Function: elevates & retracts mandible

Origin: temporal fossa

Insertion: coronoid process of mandible

Lateral pterygoid (function, origin & insertion)

Function: protraction of mandible

Origin: greater wing of sphenoid bone

Insertion: condylar process of mandible

Mylohyoid (function, origin & insertion)

Function: elevates hyoid bone

Origin: mandible

Insertion: hyoid

Digastric (function, origin, & insertion)

Function: depresses mandible

Origin: low margin of mandible

Insertion: connective tissue to hyoid

Genioglossus (function, origin & insertion)

Function: protracts & depresses tongue

Origin: mandible

Insertion: hyoid bone & tongue

Styloglossus (function, origin & insertion)

Function: elevates and retracts tongue

Origin: styloid process of temporal bone

Insertion: tongue

Palatoglossus (function, origin & insertion)

Function: elevates posterior tongue

Origin: palatine aponeurosis

Insertion: tongue

Hyoglossus (function, origin, & insertion)

Function: retracts, protracts, & depresses tongue

Origin: hyoid bone

Insertion: lateral portion of tongue

Sternocleidomastoid (function, origin, & insertion)

Function: flexion of neck

Origin: manubrium of sternum & clavicle

Insertion: Mastoid process of temporal bone

Splenius capitus (function, origin, & insertion)

Function: extension of head & neck

Origin: C7-T3 vertebrae

Insertion: mastoid process of temporal bone

Scalenes (anterior & posterior) (function, origin, & insertion)

Function: lateral flexion of neck

Origin: cervical vertebrae

Insertion: ribs

Spinalis (function, origin, & insertion)

Function: extends and laterally flexes spine

Origin: L1, L2, T11, T12, C7, T1, T2

Insertion: T4-T8, C2-C4

Psoas major (function, origin & insertion)

Function: flexion of hip

Origin: lumbar vertebrae

Insertion: lesser trochanter of femur

Rectus abdominus (function, origin, & insertion)

Function: spinal flexion

Origin: pubic symphysis

Insertion: costal cartilage & sternum

External oblique (function, origin, & insertion)

Function: flexes, lateral flexion, & rotation of trunk

Origin: external surface or ribs

Insertion: linea alba & pubic crest

Internal oblique (function, origin, & insertion)

Function: flexes, lateral flexion, & rotation of trunk

Origin: lumbar fascia & iliac crest

Insertion: linea alba & pubic crest

Quadratus lumborum (function, origin, & insertion)

Function: extension of spine

Origin: iliac crest

Insertion: lumbar vertebrae

Diaphragm

Function: expands and contracts chest cavity

Origin: sternum, ribs, & vertebrae

Insertion: central tendon

External intercostals

Function: elevates ribcage

Origin: inferior border of rib above

Insertion: superior border of rib below

Internal intercostals

Function: depresses ribcage

Origin: superior border of rib below

Insertion: inferior border of rib above

Transversus abdominus (function, origin, & insertion)

Function: compresses abdomen

Origin: inguinal ligament & iliac crest

Insertion: linea alba & pubic crest

Pectoralis minor (function, origin, insertion)

Function: protracts scapula

Origin: ribs

Insertion: coracoid process of scapula

Trapezius (function, origin, & insertion)

Function: elevates, rotates, and retracts scapula

Origin: occipital bone

Insertion: acromion and spine of scapula

Levator scapulae (function, origin & insertion)

Function: elevates & adducts scapula

Origin: C1-C4

Insertion: medial border of scapula

Rhomboideus major/minor

Function: retracts & adducts scapula

Origin: T1-T5

Insertion: medial border of scapula

Serratus anterior

Function: rotates and abducts scapula

Origin: ribs

Insertion: scapula

Deltoid

Function: flexes and abducts shoulder

Origin: clavicle and scapula

Insertion: deltoid tuberosity of humerus

Pectoralis major

Function: adducts & medially rotates shoulder

Origin: clavicle & sternum

Insertion: intertubercular sulcus of humerus

Coracobrachialis

Function: flexes & adducts shoulder

Origin: coracoid process

Insertion: humerus

Biceps brachii (2 heads)

Function: flexes & supinates elbow and forearm

Origin: coracoid process & supraglenoid tubercle

Insertion: radial tuberosity

Triceps brachii

Function: extends elbow

Origin: posterior humerus

Insertion: olecranon of ulna

Latissimus dorsi

Function: extends, adducts, and rotates arm

Origin: vertebrae, ribs, iliac crest

Insertion: intertubercular sulcus of humerus

Teres major

Function: medially rotates humerus

Origin: inferior angle of scapula

Insertion: intertubercular sulcus of humerus

Supraspinatus

Function: abducts humerus

Origin: supraspinous fossa of scapula

Insertion: greater tubercle of humerus

Infraspinatus

Function: lateral rotates humerus

Origin: infraspinous fossa

Insertion: greater tubercle of humerus

Teres minor

Function: laterally rotates humerus

Origin: lateral side of scapula

Insertion: greater tubercle of humerus

Brachialis

Function: flexes elbow

Origin: anterior humerus

Insertion: coronoid process of ulna

Brachioradialis

Function: flexes elbow

Origin: distal end of humerus

Insertion: radial styloid process

Pronator teres

Function: pronates forearm

Origin: humerus and coronoid process of ulna

Insertion: radius

Pronator quadratus

Function: pronates forearm

Origin: distal, anterior ulna

Insertion: distal, anterior radius

Supinator

Function: supinates forearm

Origin: lateral epicondyle of humerus

Insertion: proximal end of radius

Flexor carpi radialis

Function: flexes wrist

Origin: medial epicondyle of humerus

Insertion: metacarpals

Flexor carpi ulnaris

Function: flexes wrist

Origin: medial epicondyle of humerus

Insertion: metacarpals

Palmaris longus

Function: flexes hand

Origin: medial epicondyle of humerus

Insertion: palmar aponeurosis

Extensor carpi muscles

Function: extends wrist

Origin: lateral epicondyle of humerus

Insertion: metacarpals