Muscular system

What type of muscle is responsible for voluntary movements and is attached to bones?

Skeletal Muscle

What type of muscle is found in the heart and is involuntary?

Cardiac Muscle

What type of muscle is found in the walls of hollow organs and is involuntary?

Smooth Muscle

What neurotransmitter is critical for transmitting signals from nerves to muscles?

Acetylcholine (ACh)

What theory explains how muscles contract by the sliding of actin and myosin filaments?

Sliding Filament Theory

What forms the cross-bridges during muscle contraction?

Myosin heads binding to actin filaments

What is a motor unit composed of?

A motor neuron and the muscle fibers it controls

What are the positive effects of aerobic exercise?

Increased endurance, improved cardiovascular health, and better oxygen delivery to muscles

How is ATP supplied to muscles rapidly for short bursts of activity?

Creatine Phosphate (CP) Breakdown

What type of respiration occurs without oxygen and produces lactic acid?

Anaerobic Respiration

What type of respiration requires oxygen and produces ATP efficiently?

Aerobic Respiration

How do muscles move bones?

Muscles contract and pull on tendons attached to bones, allowing movement at joints.

What are muscle fibers?

Elongated cells with many nuclei, containing myofibrils made up of sarcomeres.

What are the characteristics of skeletal muscle?

Voluntary, striated, multinucleated fibers.

What type of muscle has striated, branched fibers and is found in the heart?

Cardiac Muscle

What type of muscle is non-striated and found in hollow organs?

Smooth Muscle

What are the two protein filaments involved in muscle contraction?

Actin (Thin Filament) and Myosin (Thick Filament)

What is a fascicle in muscle anatomy?

A bundle of muscle fibers (cells).

What is a sarcomere?

The functional unit of muscle contraction between two Z-discs in a myofibril.

What are anabolic steroids?

Synthetic substances that mimic testosterone and increase muscle growth.

What are isometric contractions?

Muscle contractions generating tension without changing length.

What are isotonic contractions?

Muscle contractions changing length.

What is muscle atrophy?

Decrease in muscle size due to lack of use or illness.

What is lactic acid?

A byproduct of anaerobic respiration that leads to muscle fatigue.

What does irritability refer to in muscle fibers?

The ability to respond to stimuli.

What is contractility?

The ability of muscle fibers to contract in response to stimuli.

What is the state of being unable to continue contracting due to energy depletion called?

Fatigued.

What is hypertrophy in muscle context?

Increase in muscle size from strength training.

What is perimysium?

Connective tissue surrounding a muscle fascicle.

What is epimysium?

Connective tissue surrounding the entire muscle.

What is endomysium?

Connective tissue surrounding individual muscle fibers.

What is the location of the eye muscles?

Control eye movements.

Which muscle raises the eyebrows and wrinkles the forehead?

Frontalis.

Which muscle allows movements like closing the mouth and pursing lips?

Orbicularis oris.

What muscle moves the arm in various directions?

Deltoid.

What muscle stabilizes the shoulder blades?

Trapezius.

What does the latissimus dorsi muscle do?

Extends, adducts, and rotates the arm.

What action does the biceps brachii muscle perform?

Flexes the elbow.

What is the function of the rectus abdominis?

Flexes the spine and compresses abdominal contents.

Which muscle rotates and laterally flexes the trunk?

Obliques.

What muscle is the primary calf muscle involved in plantar flexion?

Gastrocnemius.

What do the quadriceps muscles do?

Extend the knee.

What do the hamstring muscles do?

Flex the knee.

What muscle helps rotate and tilt the head?

Sternocleidomastoid.

What muscle flexes, abducts, and externally rotates the hip?

Sartorius.