TEAS Muscle System

The main functions of the muscular system include producing movement, maintaining __, generating heat, stabilizing joints, and moving substances through the body.

posture

Skeletal muscle is __ and attached to bones, responsible for body movements.

voluntary

Cardiac muscle is found only in the __ and is responsible for pumping blood continuously.

heart

Smooth muscle is __ and found in organs and blood vessels, moving food and controlling vessel diameter.

involuntary

In the basic muscle structure, the order is Muscle → __ → Muscle fiber → Myofibril.

Fascicle

Myofibrils contain __, the thin filament, and myosin, the thick filament.

actin

The muscle contracts when __ pulls actin during muscle contraction.

myosin

Muscle contraction requires __ and energy (ATP).

Calcium (Ca²⁺)

Without ATP, muscles can experience __ or stiffness.

fatigue

Antagonistic muscle pairs work by one muscle __ while the other relaxes.

contracting

The biceps __ the arm, while the triceps extends it.

flexes

Skeletal muscle is controlled by the __ nervous system.

somatic

Smooth and cardiac muscle are controlled by the __ nervous system.

autonomic

Muscle types focus on function rather than __ anatomy.

deep

Key identifying feature of cardiac muscle is its __, allowing rapid electrical signaling.

intercalated disc

Skeletal muscle fibers are __, cylindrical, and multinucleated.

striated

Smooth muscle cells are __-shaped and contain a single central nucleus.

spindle

Calcium binds to __ to trigger the exposure of binding sites on actin.

troponin

Acetylcholine (ACh) is released at the __ junction to signal muscle contraction.

neuromuscular

The tiny gap between the nerve and muscle fiber is called the __ cleft.

synaptic

The release of sodium ions into the muscle cell after ACh binds leads to an electrical impulse and __ of the muscle.

contraction

Acetylcholinesterase is an enzyme that breaks down ACh to stop the __.

contraction

Muscles are responsible for __ heat as part of thermogenesis.

generating

Involuntary muscle types are smooth and __.

cardiac

Basic muscle structure progresses from muscle to fascicle to muscle fiber to __.

myofibril

Muscle contraction follows the __ filament theory.

sliding

The biceps and triceps represent an example of __ muscle pairs.

antagonistic

The diaphragm is responsible for __ during respiration.

breathing

Myofibrils contain __ and myosin for muscle contraction.

actin

Skeletal muscle is known for its __ appearance and ability to generate movement.

striated

Calcium released from the sarcoplasmic reticulum is crucial for causing __ in muscle fibers.

contraction

Acetylcholine acts as the __ messenger at the neuromuscular junction.

chemical

Skeletal muscle is __ controlled and allows for voluntary movement.

voluntarily

In cardiac muscle, cells are __ and striated with intercalated discs.

branched

The contraction of smooth muscle influences the diameter of __ and other organs.

blood vessels

Function of the quadriceps is to __ the knee.

straighten

Function of the hamstrings is to __ the knee.

bend

Skeletal muscle's external control comes from the __ nervous system.

somatic

Calcium ions are released from the __ reticulum during muscle contraction.

sarcoplasmic

The appearance of smooth muscle is __ and it has a single nucleus.

non-striated

To initiate muscle contraction, __ must bind to receptors on the muscle fiber surface.

ACh (Acetylcholine)

The neuromuscular junction acts as a __ where nervous signals meet muscle fibers.

bridge

Actin are __ filaments in muscle contraction, while myosin are thick filaments.

thin

Skeletal muscle attaches to bones via __.

tendons

During antagonistic muscle actions, the biceps flexes while the __ extends the arm.

triceps

Acetylcholine is essential for transmitting signals across the _ cleft.

synaptic

Muscle contractions need both energy in the form of AT and the presence of __.

calcium (Ca²⁺)

Muscles primarily are for producing __ and moving substances through the body.

movement

Skeletal muscle is responsible for generating __, which helps maintain body temperature.

heat

Cardiac muscle can be identified by its __ appearance and specialized functions.

striated

Skeletal muscle has a __ appearance due to its long cylindrical fibers.

striped

Calcium ions trigger the exposure of binding sites on __ for muscle contraction to occur.

actin

__ muscle is not under conscious control and makes up the walls of organs.

Smooth