week 4

Question 1

what is the anatomical position

Answer 1

standing straight, upper limbs by the sides with palms facing anteriorly, lower limbs together with toes facing anteriorly, head and eyes facing forwards.

Question 2

what are the three cardinal planes and axes of the body?

Answer 2

coronal (anterior and posterior), sagital (medial and lateral), and transverse (superior and inferior).

Question 3

what are flexion and extension?

Answer 3

flexion is bending, decreasing the angle between bones or moving a limb anteriorly. Extension is straightening, increasing the angle between bones or moving a limb posteriorly.

Question 4

what is abduction and adduction?

Answer 4

abduction is moving away from the midline. adduction is moving towards the midline.

Question 5

what is elevation and depression?

Answer 5

elevation is movement in a superior direction whilst depression is movement in an inferior direction.

Question 6

what is protrusion and retrusion?

Answer 6

protrusion is movement anteriorly. retrusion is movement posteriorly.

Question 7

what is protraction and retraction?

Answer 7

protraction is anterolateral movement of the scapula. retraction is posterolateral movement of the scapula.

Question 8

what is pronation and supination?

Answer 8

pronation is rotation of radius medially so the palm faces posteriorly from anatomical position. supination is rotating the radius laterally so the palm faces anteriorly from anatomical position.

Question 9

what is dorsiflexion and plantarflexion?

Answer 9

dorsiflexion is flexing the ankle joint, lifting the front of the foot and toes off the ground. Plantarflexion is bending the foot and toes towards the ground.

Question 10

what is eversion and inversion?

Answer 10

eversion is movement of the sole of the foot away from the midline. inversion is movement of the sole of the foot towards the midline.

Question 11

what are the properties of muscular tissue?

Answer 11

they respond to stimuli to produce action potentials, they contract when stimulated, they stretch without being damaged and can return to original length and shape after contraction and extension.

Question 12

what is the structure of skeletal muscle?

Answer 12

epimysium, muscle, perimysium, fascicle, endomysium, muscle fibre.

Question 13

what are circular fascicles?

Answer 13

circular fascicles are arranged into concentric rings. they surround external body openings. an example is the orbicularis oris.

Question 14

what are convergent fascicles?

Answer 14

convergent fascicles are triangular or fan shaped and converge towards a single tendon of insertion. an example is the pectoralis major.

Question 15

what are parallel fascicles?

Answer 15

the length of the muscle runs parallel to the long axis of the muscle. an example is the biceps brachii or the sartorius.

Question 16

what are pennate fascicles?

Answer 16

pennate fascicles are short and attach obliquely. unipennate fascicles insert onto one side of the tendon, bipennate fascicles insert onto the tendon from opposite sides and multipennate fasicles insert onto the tendon from many directions.

Question 17

what are tendons?

Answer 17

fibrous tissue linking a muscle belly to attachment site at bone.

Question 18

what is raphe?

Answer 18

a line of ribrous tissue where one muscle joins to another.

Question 19

what is an isometric contraction, concentric contraction and eccentric contraction?

Answer 19

an isometric contraction refers to a muscle contracting but not shortening (plank). a concentric contraction refers to a muscle contracting and shortening (bicep curl). an eccentric contraction refers to a muscle relaxing and extending (lowering barbell from bicep curl).

Question 20

what is a prime mover, synergist, antagonist and fixator?

Answer 20

a prime mover is the muscle primarily responsible for producing the movement and the synergist is a muscle which assists the prime mover. the antagonist is the muscle which opposes the action of the prime mover. the fixator is a muscle which steadies the proximal part of the limb and helps move the distal part or the limb.

Question 21

describe how the action of a muscle can be inferred by the position of the muscle relative to the joint it crosses.

Answer 21

a muscle that crosses on the anterior side of a joint produces flexion. a muscle that crosses on the posterior side of a joint produces extension. a muscle that crosses on the lateral side of a joint produces abduction. a muscle that crosses on the medial side of a joint produces adduction.

Question 22

what is the function of osteoblasts and osteoclasts?

Answer 22

osteoblasts synthesise and secrete collage fibres to build bone. osteoclasts release lysosomal enzymes and acids to digest bone.

Question 23

what are the processes of bone formation (ossification)?

Answer 23

all bones are derived from mesenchyme (embryonic connective tissue).

1. intramembranous ossification: mesenchyme forms during embryonic period, and directly becomes bone.
2. endochondral ossification: mesenchyme becomes cartliage during feotal period, and bone eventually replaces cartliage. the epiphyseal plate begins as cartliage and ossified once bone length is achieved .

Question 24

How is longitudinal bone growth achieved?

Answer 24

involved two events:
1. interstitial growth of cartilage (chondrocytes) on the epiphyseal side of the epiphyseal plate.
2. replacement of cartliage on the diaphyseal side with bone via endochondral ossification.

the thickness of the epiphyseal plate remains constant, but bone on diaphyseal side increases in length.

Question 25

name the 3 types of cartliage found in the body and give an example of where each type of cartliage can be found.

Answer 25

1. hyaline: smooth, reduces friction between bones.
2. elastic: flexible, forms discrete structures in external ear, auditory tube, parts of larynx.
3. fibrocartilage: more dense network of collagen. withstands high stress and pressure.

Question 26

what are the types of joints/articulations?

Answer 26

1. synovial: bones united by a joint/articular cavity.
2. fibrous: bones united by fibrous tissue, held together by dense irregular connective tissue, no joint cavity, solid, minimal movement.
3. cartilaginous: bones unites by hyaline or fibrocartilage, solid, minimal movement.

Question 27

what are the two types of cartilaginous joints?

Answer 27

1. synchondroses (primary): a plate of hyaline cartilage between two ossification centres of developing bone (epiphyseal plates/hyaline cartilage.
2. symphyses (secondary): fibrocartilage connecting two seperate bones (intervertebral discs, pubic symphysis).

Question 28

What are the three types of Fibrous tissue?

Answer 28

1. sutures: thin layer of connective tissue called a sutural ligament (only present in the skull).
2. syndesmosis: occurs where two adjacent bones are linked by a ligament.
3. gomphosis: short collagen fibres running between the root of a tooth and its bony socket.

Question 29

what is the structure of a synovial joint?

Answer 29

a synovial joint contains hyaline cartilage, covering the surface of bones, a joint capsule, containing an inner synovial membrane (highly vascular and produces synovial fluid) and an outer fibrous membrane (dense connective tissue, may thicken to form ligaments) and accessory structures.

Question 30

what is a plane joint?

Answer 30

a plane joint allows for sliding or gliding (non-axial) movements when one bone moves across the surface of another (metacarpals and carpals)

Question 31

What is a hinge joint?

Answer 31

A hinge joint allows for movement at right angles (uniaxial movement), producing flexion and extension (humerus and ulna)

Question 32

What is a pivot joint?

Answer 32

a pivot joint allows for movement in line with the longitudinal axis of the bones (uniaxial movement), producing rotation (radius and ulna)

Question 33

What is a condular joint?

Answer 33

a condular joint allows movement around two axes at right angles (biaxial movement), producing flexion, extension, adduction and abduction (phalanges and metacarpals).

Question 34

What is a saddle joint?

Answer 34

a saddle joint allows movement around two axes (biaxial movement) at right angles. bones are saddle shaped, producing flexion, extension, adduction and abduction ( metacarpal and trapezium).

Question 35

What is a ball and socket joint?

Answer 35

a ball and socket joint allows movement around multiple axis, producing flexion, extension, adduction, abduction, circumduction and rotation (scapula and humerus).

Question 36

What are factors which affect joint mobility?

Answer 36

• structure/shape of articulating bones
• strength and tension of joint ligaments
• arrangement and tension of muscles
• contact of soft parts
• hormones
• disuse

Question 37

What is the function of the vertebral body?

Answer 37

• weight bearing
• articulate superiorly and inferiorly
• epiphyseal ring

Question 38

What is the structure and function of the vertebral arch?

Answer 38

the vertebral arch is composed of two pedicles and a lamina. it protects the spinal cord.

Question 39

What is the function of the Spinous & Transverse Processes

Answer 39

acts as levels for muscle attachment and levels for ligamentous attachment.

Question 40

What is the function of the articular processes?

Answer 40

projections with articular facets. articulate superiorly and inferiorly.