MSS 2 Exercise Science: Skeletal System - Bones and Joints

Flashcards reviewing human skeletal system anatomy, joint classifications, bone categories, and bone growth factors based on the lecture transcript.

How many fused bones are typically present in an adult skeletal structure?

Approximately $206$ fused bones.

By what age is complete bone fusing expected to occur in humans?

By around $21$ to $25$ years of age.

Approximately how many bones is an infant born with prior to ossification?

Roughly $270$ bones.

What are the three main classifications of joints in the human body?

Fibrous joints, synovial joints, and cartilaginous joints.

What is the structural characteristic and purpose of a fibrous joint?

It consists of dense, fibrous connective tissue designed to permit effectively no movement.

How many bones make up an infant skull before fusing into the cranium?

Approximately $20$ to $22$ bones.

Which natural hormone is released during pregnancy to increase movement in the pubic symphysis?

Relaxin.

How long can the hormone relaxin take to return to normal levels after childbirth?

Up to $2$ years.

What condition involves inflammation or movement of the pubic symphysis, leading to pelvic instability?

Osteitis pubis.

What structure acts as a fibrous joint connecting the radius and ulna in the forearm?

The interosseous membrane.

Which ribs attach directly to the sternum via cartilaginous joints?

Ribs $T_1$ through $T_{10}$.

What is the primary function of a bursa in a synovial joint?

It is a gel-like shock-absorbing pad that prevents friction between moving structures, such as ligaments and bones.

What is the function of a ligament?

To connect bone to bone and provide structural integrity and stability to joints.

What structure holds and encompasses the synovial fluid inside a joint?

The synovial membrane.

Which joint treatment involves passing a needle through the articular capsule into the joint cavity to reduce inflammation?

A cortisone injection.

What is the function of the meniscus in the knee joint?

It consists of strong cartilage pads forming craters on top of the tibia that fit the rounded end of the femur, improving joint stability and alignment.

What type of synovial joint exists between the $C_1$ and $C_2$ cervical vertebrae?

A pivot joint.

What type of synovial joint connects the carpals to the metacarpals at the base of the knuckles/thumb?

A saddle joint.

How much ground reaction force goes through the heel during running relative to body weight?

$1.5$ to $3$ times body weight.

What type of joint connects the radius to the carpal bones of the wrist?

A condyloid joint.

Why is the scapulothoracic joint classified as a pseudo joint?

Because it lacks anatomical joint features like a joint capsule, joint cavity, synovial fluid, or articular cartilage, and is entirely supported by muscles.

Which anatomical landmark on the pelvis is used to locate skinfold test sites?

The anterior superior iliac spine (ASIS).

Which landmark is used to determine the halfway point of the femur when measuring thigh girth?

The lateral epicondyle of the femur.

Which bony landmark is used to locate chest compressions for CPR in first aid?

The xiphoid process.

Which scapular landmark is used to assess forward head posture and neutral spine alignment?

The acromion process.

What are the four main categories of bones in the human body?

Long bones, short bones, flat bones, and irregular bones.

What cavity inside a long bone contains yellow bone marrow?

The medullary cavity.

Where does longitudinal growth occur in a long bone?

At the epiphyseal growth plates located at the ends of the bone.

What are the key characteristics and functions of short bones?

They are cube-like (as short as they are wide) and designed to absorb and distribute large forces in regions like the wrist and ankle.

What is the primary definition and role of flat bones?

They are protective structures that provide attachment points and protection for vital organs (e.g., sternum, skull, scapula, hip bone).

What are the three movable regions of the vertebral column?

The cervical, thoracic, and lumbar regions.

What posterior structure on a vertebra helps protect the spinal cord from direct rear impacts?

The spinous process.

What is the primary example of a sesamoid bone in the human body?

The patella.

What functions does the patella serve in the knee joint?

It protects the inner structures of the knee and increases the mechanical advantage of the quadriceps muscle group.

How do tendons and ligaments differ in blood supply and recovery capacity?

Tendons have a high blood supply and recover well from injury/training, whereas ligaments have a poor blood supply and take significantly longer to heal or require surgical reattachment.

How much force was recorded passing through cricketer Brett Lee's heel during his delivery stride landing?

$7$ to $11$ times his body weight.

At what birth age does bone growth and mass typically peak?

At $35$ years of age.

Which researcher from Western Australia is well-known for studies on 'anabolic aging'?

Professor Rob Newton.

What primary hormone decreases post-menopause, leading to accelerated bone mineral density loss in females?

Estrogen.

Which vitamin synthesized from sunlight exposure is crucial for bone mineral uptake?

Vitamin D.