muscular tissue

Question 1

skeletal muscle:

Answer 1

usually attach to bones
striated
mainly voluntary, some involuntary control

Question 2

cardiac muscle

Answer 2

wall of the heart
striated
involuntary

Question 3

smooth muscle

Answer 3

walls of hollow internal structures
not striated
involuntary

Question 4

What does it mean for a muscle to be “striated”?

Answer 4

it means that the myofilaments are arranged into organized bands that are visible under a microscope.

Question 5

Which muscles are striated?

Answer 5

Both skeletal muscle and cardiac muscle are striated.

Question 6

How are skeletal muscles controlled?

Answer 6

Skeletal muscles are mainly under voluntary control and innervated by the somatic nervous system.

Question 7

Which nervous system controls cardiac and smooth muscles?

Answer 7

under involuntary control and innervated by the autonomic nervous system.

Question 8

How do smooth muscle filaments appear compared to skeletal and cardiac muscle?

Answer 8

Smooth muscle filaments appear more disorganized compared to skeletal and cardiac muscle.

Question 9

What are the individual cells that make up muscle tissue called?

Answer 9

Muscle fibers.

Question 10

What triggers an electrical signal in the cell membrane of a muscle fiber?

Answer 10

Certain stimuli, such as nervous or endocrine signals.

Question 11

What happens to the electrical signal once it’s triggered in a muscle fiber?

Answer 11

It is propagated along the length of the muscle fiber.

Question 12

What occurs as the electrical signal travels along the muscle fiber?

Answer 12

The overlapping filaments inside the cell “walk” along each other.

Question 13

What does the movement of overlapping filaments generate within the muscle fiber?

Answer 13

It generates tension at either end of the muscle fiber.

Question 14

How does muscle contraction affect bones?

Answer 14

When skeletal muscles contract, each end of the muscle will pull on the bone that it is attached to.

Question 15

What is the length-tension relationship in muscles?

Answer 15

It refers to the relationship between muscle length and the amount of tension a muscle can generate.

Question 16

How does muscle length affect tension development?

Answer 16

The muscle length that allows for maximum overlap tends to lead to higher tension development, while shorter or longer muscle lengths have less overlap and tend to lead to lower tension development.

Question 17

What is a muscle filament?

Answer 17

A muscle filament refers to the long protein strands found within muscle cells

Question 18

The filaments within each muscle cell are arranged into organized bands called:

Answer 18

striations

Question 19

The cells in each muscle are surrounded by:

Answer 19

connective tissue coverings

Question 20

What does it mean for a muscle to be “striated”?

Answer 20

the myofilaments within their muscle fibers are arranged into organized bands that are visible under a microscope.

Question 21

What is the connective tissue covering surrounding each muscle fiber called?

Answer 21

Endomysium.

Question 22

What are muscle spindles organized into?

Answer 22

Bundles called fascicles.

Question 23

What is the connective tissue covering surrounding each fascicle called?

Answer 23

Perimysium

Question 24

What is the connective tissue covering surrounding the entire muscle called?

Answer 24

Epimysium

Question 25

purpose of the protective covering called the epimysium:

Answer 25

protects the muscle from friction against other muscles and bones

Question 26

what are the fascicliae contained within?

Answer 26

the perimysium

Question 27

Muscle Fiber (Muscle Cell)

Answer 27

A muscle fiber is like a single rubber band. It’s the basic unit of skeletal muscle.

Question 28

Muscle Fascicles

Answer 28

Muscle fascicles are bundles of muscle fibers, similar to bunches of rubber bands tied together. They make up the bulk of skeletal muscle tissue.

Question 29

Epimysium

Answer 29

Epimysium is like a layer of plastic wrap surrounding a bunch of rubber bands. It wraps around the entire muscle, providing support and protection.

Question 30

Perimysium

Answer 30

Perimysium is like smaller pieces of plastic wrap wrapping around each bunch of rubber bands within the larger bundle. It surrounds each fascicle, providing support and facilitating nutrient exchange.

Question 31

Endomysium

Answer 31

Endomysium is like even smaller pieces of plastic wrap surrounding each individual rubber band within a bunch. It surrounds each muscle fiber, providing support and facilitating nutrient and waste exchange.

Question 32

Myofibrils

Answer 32

Myofibrils are tiny structures inside muscle fibers, like individual threads that make up a rubber band. They’re responsible for muscle contraction.

Question 33

Sarcomeres

Answer 33

Sarcomeres are sections along the rubber band (myofibril) with specific patterns. They contain proteins that allow muscles to contract and relax.

Question 34

Actin and Myosin

Answer 34

Actin and myosin are the main proteins found in sarcomeres. Actin is like the thin threads in the rubber band, and myosin is like the thicker threads. They work together to make the rubber band contract when your muscles move.

Question 35

Tendon

Answer 35

A tendon is a band of dense connective tissue that attaches a skeletal muscle to a bone.

Question 36

what type of structure is a tendon and what does it form?

Answer 36

typically cord-like in structure, but can occasionally be broad or flat, forming an aponeurosis.

Question 37

Aponeurosis

Answer 37

An aponeurosis is a broad, flat sheet of dense connective tissue that attaches muscles to other structures, such as bones or other muscles. It serves a similar function to tendons but has a flattened shape.

Question 38

what can tendons be covered by?

Answer 38

a tendon sheath, which consists of layers that slide along each other as the tendon moves, reducing friction.

Question 39

what don tendon sheaths functions similarly to?

Answer 39

function similarly to bursa and reduce friction between a tendon and its surrounding tissue as the muscle contracts.

Question 40

What is the dense sheet of connective tissue that lines the body wall, supports skeletal muscles and internal organs, and separates muscle compartments in the limbs?

Answer 40

Fascia

Question 41

What does fascia do in the limbs?

Answer 41

In the limbs, fascia separates each region into compartments whose muscles tend to have similar actions and innervation.

Question 42

What are the thickened bands of fascia around some joints called, which help keep tendons anchored down?

Answer 42

Retinacula

Question 43

example of a retinaculum

Answer 43

The transverse humeral ligament near the shoulder joint

Question 44

What are intercalated discs?

Answer 44

specialized junctions between cardiac muscle cells. They contain gap junctions that allow for the transmission of action potentials between cells, aiding in the coordination of heart muscle contractions.

Question 45

What are the characteristics of cardiac muscle fibers?

Answer 45

Like skeletal muscle, the filaments within each muscle fiber are striated.
Individual muscle fibers are connected by intercalated discs.
These discs contain small channels called gap junctions that allow action potentials to be transmitted from one cell to another, aiding in the coordination of the heart’s pumping action.

Question 46

What is a gap junction?

Answer 46

a tiny tunnel between cells that lets them share signals and molecules directly with each other.

Question 47

cardiac muscle fibers are transmitted to other fibers through small channels called gap junctions. Why is this crucial?

Answer 47

coordinated and rhythmic contractions in the heart.

Question 48

What distinguishes smooth muscle filaments from skeletal and cardiac muscle filaments?

Answer 48

filaments are not striated, allowing for greater ability to shorten and stretch.

Question 49

How do action potentials get transmitted between individual smooth muscle fibers?

Answer 49

Similar to cardiac muscle, occasional small channels between individual smooth muscle fibers permit the transmission of action potentials between cells.

Question 50

functions of muscular tissue:

Answer 50

movement, stabilizes body positions and posture, generates heat

Question 51

Contraction of cardiac muscle

Answer 51

pumps blood through the circulatory system.

Question 52

Contraction of smooth muscle in blood vessels

Answer 52

regulates blood flow to different regions of the body.

Question 53

Contraction of smooth muscle in the digestive organs

Answer 53

moves material through the digestive system.

Question 54

Contraction of smooth muscle in the urinary organs

Answer 54

moves urine through the urinary system.

Question 55

Contractions of smooth muscle in sphincters located throughout the body

Answer 55

cause the storage of materials and regulate their release.

Question 56

Some sphincters are composed of skeletal muscle and are therefore under ___ control

Answer 56

voluntary

Question 57

Origin

Answer 57

The attachment that does NOT move
(proximal attachment)

Question 58

Belly

Answer 58

The “fleshy” portion of the muscle in the middle

Question 59

Insertion

Answer 59

The attachment that moves
(distal attachment)

Question 60

Action

Answer 60

Movement(s) that occur(s) when the muscle contracts

Question 61

Innervation

Answer 61

The motor nerve supply to the muscle