Muscular System

Question 1

Role of muscles, bones and nerves

Answer 1

Muscles move you
Bones hold you up
Nerves tell the muscles to move the bones

Question 2

Muscles are made of and move….

Answer 2

Muscles are primarily composed of elastic fibers bundled together, forming fascicles which are wrapped in connective tissue, that contract and relax to cause movement.
Within each fiber are smaller units called myofibrils, which contain protein filaments that interact to cause muscle contraction.

Question 3

Skeletal muscles

Answer 3

Voluntary muscles that attach to bones via tendons, allowing for movement and other functions like posture and body temperature regulation. They are striated (striped) in appearance and are under the control of the somatic nervous system.

Question 4

Smooth muscles

Answer 4

Are involuntary, non-striated muscles that line the walls of various organs and structures including the digestive tract, blood vessels, and airways. They move food through the intestines, regulate blood pressure, and control airflow in the lungs. They are regulated by the autonomic nervous system.

Question 5

Cardiac muscles

Answer 5

Involuntary, specialized muscle tissue that forms the walls of the heart, responsible for the rhythmic contractions that pump blood throughout the body. Characterized by their branched, cylindrical shape, and striated appearance

Question 6

Sarcomere

Answer 6

The basic unit of a myocyte (muscle fiber) and is comprised of two main protein filaments (thin actin and thick myosin filaments) which are the active structures responsible for muscular contraction.

Question 7

Tendons

Answer 7

Each muscle has 2 tendons
Tendons are tough, fibrous connective tissues that connect muscles to bones, enabling movement by transmitting the force of muscle contractions. They are primarily composed of collagen and are relatively inelastic, resisting high forces. Tendons are essential for various body movements and can be injured through overuse or sudden exertion.

Question 8

Origin

Answer 8

the origin refers to the less movable attachment point of a muscle, typically proximal (closer to the body). Essentially, the origin is the “fixed” point

Question 9

Insertion

Answer 9

The insertion is the more movable attachment point, usually distal (further from the body) and moves the bone or joint during contraction. The insertion is the “moving” point

Question 10

agonist

Answer 10

The primary muscle responsible for a specific movement or action, also known as the prime mover. When a muscle contracts to initiate a movement, it’s the agonist muscle, while other muscles may assist or oppose it.
Key fact. One way to remember which muscle is the agonist – it’s the one that’s in ‘agony’ when you are doing the movement as it is the one that is doing all the work.

Question 11

antagonist

Answer 11

the muscle that is relaxing or lengthening is called the antagonist.

Question 12

Postural muscles

Answer 12

A group of muscles that primarily work to maintain upright posture and balance, are crucial for stability, especially when the body is at rest or engaging in weight-bearing activities. They include deep abdominal muscles, back muscles, and muscles of the pelvis and hips.