Muscular System

Question 1

It refers to the study of the muscular system

Answer 1

Myology

Question 2

an organ system consisting of three different types of muscles: the skeletal, smooth and cardiac muscles.

Answer 2

Muscular system

Question 3

It permits movement of the body, maintains postures and circulates blood throughout the body.

Answer 3

Muscular system

Question 4

What are the five properties of the muscles

Answer 4

excitability or irritability, contractility, extensibility, elasticity, and tonicity.

Question 5

The capacity of muscles to receive and respond to stimulus.

Answer 5

Excitability

Question 6

The capacity of the muscles to shorten and tighten.

Answer 6

Contactility

Question 7

The capacity of the muscles to stretch/extend upon the application of force.

Answer 7

Extensibility

Question 8

The ability of the muscle to regain the original shape and size after being stretched.

Answer 8

Elasticity

Question 9

Excitability is the ability to respond to certain stimuli by producing electrical signals called?

Answer 9

action potentials (impulses)

Question 10

Action potentials in muscles are referred to as?

Answer 10

muscle action potentials

Question 11

Action potentials in nerve cells are referred to as?

Answer 11

nerve action potentials

Question 12

What are the functions of muscles?

Answer 12

1. Movement or locomotion
2. Heat production, heat is produced (85% body heat is derived from muscle contraction),
3. Posture, Alters diameters of tubes and vessels in the body
4. Protection of vital organs

Question 13

What are two major types of muscles aaccording to the type of action

Answer 13

Voluntarily (can be made to contract) and involuntarily (can’t be controlled by the will)

Question 14

One of the four primary tissue types of the body

Answer 14

Muscle

Question 15

The body contains three types of muscle tissue

Answer 15

skeletal muscle, cardiac muscle, and smooth muscle.

Question 16

The best-known feature of skeletal muscle is?

Answer 16

It’s ability to contract and cause movement

Question 17

2 Characteristics of skeletal muscles

Answer 17

Striated and voluntarily

Question 18

What are cardiac muscle fibers also known as?

Answer 18

Cardiocytes or heart muscle cells.

Question 19

They are physically and electrically connected, allowing the entire heart to contract as one unit, called a?

Answer 19

syncytium

Question 20

What is the built-in rhythm of the heart called?

Answer 20

Autorhythmicity.

Question 21

What is the size of a cardiac muscle fiber?

Answer 21

Length: 50-100 μm
Diameter: 10-20 μm

Question 22

2 Characteristics of Cardiac Muscle

Answer 22

Striated and Involuntary control

Question 23

Small, spindle-shaped, mononucleated with lesser actin and myosin than the skeletal muscle.

Answer 23

Smooth muscle fibers

Question 24

Ability of smooth muscle to be stretched without developing lasting high tension.

Answer 24

Plasticity

Question 25

What is the size of a smooth muscle fiber?

Answer 25

Length: 30-200 μm Width: 5-10 μm

Question 26

Where is smooth muscle primarily located?

Answer 26

walls of small intestines, blood vessels, vagina, and stomach.

Question 27

2 Characteristics of smooth muscle

Answer 27

Non-striated and involuntary

Question 28

What is a skeletal muscle composed of?

Answer 28

striated muscle cells and connective tissue.

Question 29

What are the connective tissue layers in skeletal muscle called?

Answer 29

mysia

Question 30

A dense sheet or broad band of irregular connective tissue that lines the body wall and limbs and supports and surrounds muscles and other organs of the body.

Answer 30

Fascia

Question 31

connective tissue/ fascia surrounding the muscle.

Answer 31

Epimysium

Question 32

connective tissue that extends inward from the epimysium and surrounds/envelops muscle fasciculi/ bundles of muscle fibers (fascicles).

Answer 32

Perimysium

Question 33

connective tissue that surrounds individual muscle fibers

Answer 33

Endomysium

Question 34

Skeletal Muscle Attachments

Answer 34

Tendon, aponeuroses, and tendon sheath

Question 35

a cord of dense fibrous connective tissue which becomes continuous. It attaches a muscle to the periosteum of a bone.

Answer 35

Tendon

Question 36

is a tendons that take the form of broad, flat layer of thin sheets that attach to the coverings of a bone, another muscle, or the skin. (When the connective tissue elements extend as a broad, flat sheet, it is called an?)

Answer 36

Aponeuroses

Question 37

is a tubes of fibrous connective tissue that encloses certain tendons especially those at the wrist and ankle, permit tendons to slide back and forth more easily.

Answer 37

Tendon sheath

Question 38

It is less movable and generally proximal, more fixed point of attachment, and the attachment of a muscle tendon to the stationary bone.

Answer 38

Original

Question 39

It is more movable end and is generally distal to the movable bone.

Answer 39

Insertion

Question 40

muscle in between the origin and insertion.

Answer 40

Belly or gaster

Question 41

elongated cylindrical cells that lie parallel to one another

Answer 41

Myofibers

Question 42

plasma membrane, thin membrane that surrounds the muscle fibers

Answer 42

Sacolemma

Question 43

cytoplasm of a muscle fiber, which is multinucleated.

Answer 43

Sarcoplasm

Question 44

What does the sarcoplasm contain?

Answer 44

enzymes, sarcoplasmic reticulum, and myofibrils

Question 45

a netweork of membrane enclosed tubules comparable to smooth endoplasmic reticulum

Answer 45

Sarcoplasmic reticulum

Question 46

dilated sacs of sarcoplasmic reticulum

Answer 46

Terminal cisterns

Question 47

extensions of sarcolemma that opens to the outside of the muscle fiber

Answer 47

Transverse Tubules (T-tubules)

Question 48

consists of transvers tubule and the segments of sarcoplasmic reticulum (terminal cisterns) on either side

Answer 48

Triad

Question 49

Within myofibrils are smaller protein structures called

Answer 49

filaments or myofilaments

Question 50

What are the two kinds of myofilaments in myofibrils?

Answer 50

Thin myofilaments and thick myofilaments.

Question 51

What is the diameter of thin myofilaments?

Answer 51

6 nm in diameter.

Question 52

What proteins make up thin myofilaments?

Answer 52

Thin myofilaments are composed of three proteins: (1) Tropomyosin – loosely attached to actin in strands. (2) Troponin – located at regular intervals on tropomyosin. (3) Actin – arranged in a double helix and contains myosin-binding sites.

Question 53

What are the three subunits of troponin, and what do they bind to?

Answer 53

Troponin has three subunits: I – binds to actin. C – binds to calcium. T – binds to tropomyosin.

Question 54

What is the diameter of thick myofilaments?

Answer 54

16 nm in diameter

Question 55

What protein mainly composes thick myofilaments?

Answer 55

Myosin

Question 56

contain the actin-binding site and an ATP binding site

Answer 56

Cross bridges

Question 57

contain the actin-binding site and an ATP binding site

Answer 57

Cross bridges

Question 58

- structural and functional unit of muscles - fundamental unit of muscular contraction - compartments where myofilaments of myofibrils are arranged

Answer 58

Sarcomeres

Question 59

Proteins that generate force during muscle contractions.

Answer 59

Contractile proteins

Question 60

Proteins that help switch muscle contraction process on and off.

Answer 60

Regulatory proteins

Question 61

Proteins that keep thick and thin filaments of myofibrils in proper alignment, give myofibrils elasticity and extensibility, and link myofibrils to sarcolemma and extracellular matrix

Answer 61

Structural protein

Question 62

What is the length and diameter of Cardiac Muscle?

Answer 62

50-100 um length, 10-20 um diameter

Question 63

What is the length and width of smooth muscle?

Answer 63

Length of 30-200 um, width of 5-10 um