Skeletal System
How many bones are in the adult human body?
206
What is the agonist in a movement?
The prime mover muscle responsible for initiating movement.
Which type of fibres are best for endurance activities?
Slow-twitch (Type I)
Which side of the heart pumps deoxygenated blood to the lungs?
Right side
Where does gas exchange occur in the lungs?
Alveoli
Name the three main types of joints.
Fibrous, cartilaginous, synovial
Which muscle is the antagonist during a bicep curl?
The triceps.
Which type of fibres are best for explosive, powerful movements?
Fast-twitch (Type II)
What is the function of red blood cells?
Transport oxygen and carbon dioxide.
By what process does gas exchange occur?
Diffusion
What type of joint is the hip joint, and what movement does it allow?
Ball-and-socket; allows movement in all directions
What role do stabiliser muscles play during movement?
They support the body and prevent unwanted movement at joints.
What is an isometric contraction?
Tension develops without changing muscle length (e.g., plank).
Name the two circulatory pathways.
Pulmonary and systemic circulation
What happens to oxygen and carbon dioxide during gaseous exchange?
Oxygen diffuses into the blood; carbon dioxide diffuses out into the alveoli.
What is the function of ligaments in a joint?
They connect bone to bone and provide stability while restricting excessive movement.
How do tendons assist in movement?
They attach muscle to bone, transmitting force for movement.
Describe the difference between concentric and eccentric contractions.
Concentric shortens the muscle; eccentric lengthens it under tension.
What is stroke volume?
The amount of blood pumped out of the left ventricle of the heart with each beat.
How does exercise affect gaseous exchange efficiency?
Increases breathing rate and depth, speeding up oxygen uptake and CO₂ removal.
Explain how articular cartilage contributes to joint efficiency.
It reduces friction and prevents jarring/chipping of bone surfaces during movement.
How do the skeletal and muscular systems work together to produce movement?
The skeletal system provides the rigid framework and joints, while the muscular system contracts to pull on bones via tendons, creating movement at the joints.
Explain how fibre type distribution can influence athletic performance.
A higher proportion of Type I aids endurance athletes, while more Type II supports sprinters/power athletes.
Identify two factors that can reduce cardiovascular efficiency.
Altitude, low haemoglobin, vascular disease (any two).
Explain how haemoglobin assists gaseous exchange.
It binds to oxygen in the lungs and carries it to tissues while also carrying CO₂ back to the lungs for removal.