Muscle Tissue

Question 1

THree types of muscle tissue

Answer 1

Skeletal Smooth Cardiac

Question 2

Skeletal Muscle

Answer 2

40% of the body’s weight

Responsible for voluntary movements

Attached to bones

Cell shape long and cylindrical

Question 3

Smooth msucle

Answer 3

Most widely distributed muscle in the body Involuntary; performs necessary functions such as moving food through digestive tracts, etc. The cell is spindle-shaped

Question 4

Cardiac muscle

Answer 4

Only found in the heart Contracts spontaneously and rhythmically Involuntary Cells are cylindrical and branched

Question 5

Functions of skeletal msucle

Answer 5

1) movement of pody 2) mantenance of posture 3) Respiration 4) Production of body heat 5) Communication (speaking, writing, typing, etc.)

Question 6

Function of smooth muscle

Answer 6

Constriction of organs and vessels

Question 7

Function of cardiac muscle

Answer 7

Contraction of the heart

Question 8

4 functional properties of muscle tissue

Answer 8

COntractility Excitability Extensibility Elasticity

Question 9

Contractility

Answer 9

The ability of muscle to shorten forcefully and lengthen passively

Question 10

Excitability

Answer 10

Capacity fof muscle to respond to electrical stimulus

Question 11

Extensibility

Answer 11

ability of muscle to be stretched eyond normal resting length and still be able to contract

Question 12

Elasticity

Answer 12

ability of muscle to spring back to its original resting length after beign stretched

Question 13

Skeletal muscle fibers

Answer 13

a complete skeletal muscle organic consisting of cells

Question 14

Fascicles

Answer 14

A visible bundle of connective tissue that composes a muscle

Question 15

Perimyseum

Answer 15

A layer of connecteive tissue that surrounds a fasciculus

Question 16

Epimysium

Answer 16

A layer of dense irregular collagenous connective tissue that surrounds the entire muscle

Question 17

Muscular fascia

Answer 17

Sheets of dense irregular collagenous connective tissue that separates individual muscles or groups of muscles. Located superficial to the epimysium

Question 18

Motor neurons

Answer 18

Speicalized nerve cell responsible for stimulating skeletal muscle contraction Originate in teh brain adn spinal cord and extend to skeletal muscle fibers through nerves

Question 19

Muscle fibers

Answer 19

Each cell is a muscle fiber Long, cylindrical cells Several nuclei Striated

Question 20

Myoblasts

Answer 20

multinucleated immature cells that develop muscle fibers

Question 21

Hypertrophy

Answer 21

Increase in size of muscle, not number of muscle fibers

Question 22

Sarcolemma

Answer 22

The plasma membrane of a muscle fiber

Question 23

External lamina

Answer 23

delicate connective tissue layer outside the sarcolemma

Question 24

Endomysium

Answer 24

Second layer outside the sarcolemma

Question 25

Tranverse tubules (T tubules)

Answer 25

Found along the surface of the sarcolemma

Question 26

Sarcoplasmic reticulum

Answer 26

The smooth endoplasmic reticulum of the muscle fiber

Question 27

Sarcoplasm

Answer 27

The cytoplasm of a muscle cell

Question 28

Myofibrils

Answer 28

bundles of protein filaments found in the sarcoplasm

Question 29

Myofilaments

Answer 29

Long, thin protein filaments inside a myofibril

Question 30

2 types of myofilaments

Answer 30

Actin myofilaments (thin) myosin myofilaments (thick)

Question 31

Sarcomere

Answer 31

units of actin and myosin myofilaments that are arranged in an ordered fashion or form myofibrils Basic structural and functional unity of skeletal muscle. Smallest portion of the muscle capable of contracting

Question 32

Z disks

Answer 32

Separate one sarcomere from the next

Question 33

Sarcomere striated appearance is caused by

Answer 33

2 I-bands (light stain) 1 A anisotropic band (I-band) (dark stain

Question 34

Mysoin structure

Answer 34

Question 35

Actin myofilament structure

Answer 35

Question 36

Action potentials

Answer 36

Electrical signals from motor neurons that stiumlate muscle fibermovement

Question 37

Neuromuscular junction/synapse

Answer 37

Where the motor neuron axon branches meet with muscle fiber

Question 38

ACh (acetylcholine)

Answer 38

organic molecule of acetic acid and choline. The neurotransmitter that stimulates or inhibits production of action potential

Question 39

Sliding filament model

Answer 39

How a muscle contracts. Parallel arrangement of myofilaments in a sarcomere allows them to interact

Question 40

Membrane potential

Answer 40

Charge difference across the plasma membrane of an unstimulated cell

Question 41

Two types of gated ion channels

Answer 41

Ligand-gated ion channels - open when a ligand (chemical signal like a neurotransmitter) binds to a receptor Voltage-gated ion channels - open and close in response to particular membrane potential. Na+, K+, and Ca2+ are the major ones.

Question 42

Action potential

Answer 42

Reversal of resting membrane protential Inside of plasma membrane becomes positively charged Opens ion channels, diffiusion of ions through these channels changes 2 phases - depolarization adn repolarization

Question 43

Threshold

Answer 43

Where an actional potential is triggered if depolarization is strong enough

Question 44

All or none principle

Answer 44

All action potentials are identical. If a stimulus is strong enough to produce a depolarization that reaches a threshold, or even exceeds the threshold, all of the permeability changes proceed.