MLT GlobeAnatomy: Skeletal system & joints – page 3
68 Anatomy MCQs on Skeletal system & joints with answers and explanations.
In a synovial joint, the smooth hyaline cartilage covering the ends of the bones is called:
Articular cartilage covers the bone surfaces that meet in a joint, reducing friction. Menisci are separate fibrocartilage pads, bursae are fluid sacs, and the capsule encloses the joint.
The glenohumeral (shoulder) joint allows movement in many planes because it is a:
The humeral head fits into the glenoid cavity as a ball-and-socket synovial joint, permitting flexion, extension, abduction, adduction and rotation.
A joint where a rounded head fits into a cup-shaped cavity, permitting movement in all planes, is found at the:
The glenohumeral joint is a ball-and-socket synovial joint allowing multiaxial movement. The elbow is primarily a hinge joint.
Which statement correctly describes the cervical region of the adult spine?
The cervical curve develops after birth as the infant holds up its head, so it is secondary (lordotic, concave backwards). There are seven cervical vertebrae, and the region is highly mobile.
Which statement about a typical long bone such as the femur is correct?
Long bones have a diaphysis between two epiphyses. In adults the medullary cavity holds yellow (fatty) marrow, the cavity is lined by endosteum, and articular surfaces bear hyaline cartilage.
A joint where bones are united by fibrocartilage, like a symphysis, is a secondary cartilaginous joint. Which is an example?
Intervertebral discs unite vertebral bodies by fibrocartilage (symphysis). Growth plates and the first costochondral joint are primary (hyaline) cartilaginous joints; sutures are fibrous.
Which set correctly lists paired and single bones of the adult cranial vault?
The cranium has paired parietal and temporal bones and single frontal, occipital, sphenoid and ethmoid bones—eight in total.
Which structure is made of hyaline cartilage?
Growth plates are hyaline cartilage. Menisci and discs are fibrocartilage; the epiglottis is elastic cartilage.
Which fontanelle of the newborn skull is usually the last to close, at around 18–24 months?
The diamond-shaped anterior fontanelle closes last (about 18–24 months). The posterior fontanelle closes within the first 2–3 months.
Which statement correctly describes the atlas (C1) and axis (C2)?
The ring-shaped atlas, which lacks a body, pivots around the dens of the axis below it; the transverse ligament of the atlas keeps the dens away from the spinal cord.
Counting the sacrum and coccyx as single bones, how many bones make up the adult vertebral column?
Adults have 24 separate vertebrae plus the fused sacrum and coccyx, giving 26. Before fusion there are about 33 vertebrae.
In compact bone, which channels run perpendicular to the Haversian canals, connecting them to each other and to the periosteum?
Volkmann's (perforating) canals carry vessels transversely between Haversian canals and periosteum. Canaliculi are tiny channels linking osteocytes.
The joint between the trapezium and the first metacarpal, giving the thumb opposition, is a:
The first carpometacarpal joint is the classic saddle joint, with reciprocal concave-convex surfaces allowing opposition.
How many phalanges are present in one foot?
The great toe has two phalanges and each of the other four toes has three: 2 + 12 = 14, the same as the hand.
Circumduction is possible at which of these joints?
Circumduction needs movement in two or more axes and occurs at ball-and-socket or condyloid joints such as the shoulder. Hinge and pivot joints move in one axis only.
How many articulations exist between the radius and ulna?
The radius and ulna meet at the proximal and distal radioulnar joints and are joined along their shafts by the interosseous membrane (middle radioulnar joint).
A fibrocartilaginous labrum deepens the socket of which joint?
The acetabular labrum deepens the hip socket (as the glenoid labrum does at the shoulder). The knee has menisci instead.
At the radiocarpal (wrist) joint, which carpal bones articulate with the radius?
The distal radius articulates with the scaphoid and lunate (the triquetrum contacts the articular disc). Hamate and capitate lie in the distal row.
Because cartilage has no blood vessels, how do its chondrocytes receive nutrients?
Cartilage is avascular, so nutrients diffuse through the matrix from the perichondrium or synovial fluid. This explains its slow healing.
Nodding the head up and down ("yes") takes place mainly at which joint?
Flexion and extension of the head occur between the occipital condyles and the atlas. Shaking the head "no" occurs at the atlanto-axial joint.