Muscular System

Question 1

skeletal

Answer 1

The skeletal muscle is one of the three significant muscle tissues in the human body. Each skeletal muscle consists of thousands of muscle fibers wrapped together by connective tissue sheaths.

Question 2

smooth

Answer 2

muscle tissue in which the contractile fibrils are not highly ordered, occurring in the gut and other internal organs and not under voluntary control.

Question 3

cardiac

Answer 3

Cardiac muscle makes up the thick middle layer of the heart. It is one of three types of muscle in the body, along with skeletal and smooth muscle.

Question 4

excitability

Answer 4

Excitability is the ability to respond to a stimulus, which may be delivered from a motor neuron or a hormone.

Question 5

contractility

Answer 5

Contractility is the ability of muscle cells to forcefully shorten. Contractility allows muscle tissue to pull on its attachment points and shorten with force.

Question 6

extensibility

Answer 6

Extensibility is the ability of a muscle to be stretched. … Elasticity is the ability to recoil or bounce back to the muscle’s original length after being stretched.

Question 7

elasticity

Answer 7

Tissue elasticity is the ability to stretch a muscle to reach its full range of movement without restriction.

Question 8

Fascicle

Answer 8

bundle of structures, such as nerve or muscle fibers or conducting vessels in plants

Question 9

Epimysium

Answer 9

a sheath of fibrous elastic tissue surrounding a muscle.

Question 10

Perimysium

Answer 10

the sheath of connective tissue surrounding a bundle of muscle fibers.

Question 11

Endomysium

Answer 11

The endomysium is the thinner portion of the intramuscular connective tissue and is directly in contact with and surrounds every single muscle fibre, forming its immediate external environment.

Question 12

Sarcolemma

Answer 12

the fine transparent tubular sheath which envelops the fibers of skeletal muscles.

Question 13

Myofibril

Answer 13

A myofibril is a long cylindrical organelle found in muscle cells formed by two transverse filament systems: the thick and thin filaments.

Question 14

Sarcoplasm

Answer 14

the cytoplasm of striated muscle cells.

Question 15

Actin

Answer 15

a protein that forms (together with myosin) the contractile filaments of muscle cells, and is also involved in motion in other types of cell.

Question 16

Myosin

Answer 16

Myosins are a large family of cytoskeletal motor proteins that bind actin and use the energy of ATP hydrolysis to perform diverse functions such as cell motility and contractility, cytokinesis, intracellular trafficking and muscle contraction.

Question 17

subclavius

Answer 17

It depresses the lateral clavicle, acts to stabilize the clavicle while the shoulder moves the arm.

Question 18

Serratus anterior

Answer 18

Moves arm from sides of body

Question 19

Trapezius

Answer 19

The trapezius muscle is mainly postural but is also used for active movements such as side bending and turning the head, elevating and depressing the shoulders, and internally rotating the arm

Question 20

Rhomboid

Answer 20

Retracts the scapula and rotates it to depress the glenoid cavity. It also fixes the scapula to the thoracic wall

Question 21

Pectoralis major

Answer 21

The pectoralis major’s primary functions are flexion, adduction, and internal rotation of the humerus

Question 22

Latissimus dorsi

Answer 22

The latissimus dorsi is responsible for extension, adduction, transverse extension also known as horizontal abduction

Question 23

deltoid

Answer 23

The deltoid has three distinct functions that correspond to the three bands of muscle fibers. Contraction of the anterior fibers flexes and medially rotates the arm by pulling the humerus towards the clavicle.

Question 24

supraspinatus

Answer 24

Contraction of the supraspinatus muscle leads to abduction of the arm at the shoulder joint.

Question 25

teres major

Answer 25

The main function of this muscle is to produce movements of the arm on the shoulder joint. By contracting, it pulls the humerus posteriorly (extension) and rotates it medial towards the trunk (internal rotation).

Question 26

biceps brachii

Answer 26

Primary functions of the biceps brachii is flexion of the elbow and supination of the forearm.

Question 27

pronator teres

Answer 27

As its name suggests, the main action of pronator teres is the pronation of the forearm, which is an exclusive upper limb movement.

Question 28

triceps brachii

Answer 28

The main function of triceps brachii is extension of the forearm at the elbow joint. In addition, its long head contributes to the extension and adduction of the arm at the shoulder joint.

Question 29

supinator

Answer 29

Supination refers to the rolling movement of the foot in which most of the weight of the body is transferred to the outer edge of the foot.