Muscle Anatomy And Histology

Question 1

What are the three types of muscle?

Answer 1

Skeletal, Cardiac, and Smooth

Question 2

What are features of Cardiac Muscles?

Answer 2

They push blood through arteries and veins
The have rhythmic contractions

Question 3

What are features of Smooth Muscles?

Answer 3

They push fluids and solids through the body
They are under involuntary contraction

Question 4

What are the 4 basic properties of muscles?

Answer 4

Excitability (respond to stimuli)
Contractility (ability to shorten)
Extensibility (ability to stretch)
Elasticity (ability to rebound toward original length)

Question 5

What are the functions/Features of Skeletal Muscles?

Answer 5

-Skeletal movements
-Maintain posture and body position
-Support soft tissues
-Regulate entry and exit (Swallowing, Defecation, Urination)
-Help maintain body temp
-Under voluntary control

Question 6

What converges to form tendons?

Answer 6

Epimysium, Perimysium, Endomysium

Question 7

The chemical communication between a nerve and a muscle takes place at the what?

Answer 7

Neuromuscular Junction

Question 8

What are the parts of the muscle?

Answer 8

Myofilaments
Myofibrils
Sacromeres
Sarcoplasm/Sarcoplasmic reticulum
Muscle fascicle
Muscle fibers/Satellite cells
Endo-, Peri-, and Epi- mysium

Question 9

What are facts about Myofibrils?

Answer 9

-They are made of Myofilaments (Actin [Thin filament], Myosin [Thick filament]
-They are arranged in units of sarcomeres

Question 10

What are facts of Sarcomeres?

Answer 10

They are the functional unit of muscle fibers
There are about 10,000 sarcomeres per Myofibrils
They contain overlapping actin and myosin
They create striations

Question 11

What are the levels of organization of skeletal muscle from smallest to biggest?

Answer 11

Sarcomere
Myofibril
Muscle fiber
Muscle fascicle
Skeletal muscle

Question 12

What is rigor mortis?

Answer 12

When lack of ATP causes the inability to relax muscles

Question 13

What is the neurotransmitter that helps facilitate muscle contraction?

Answer 13

Acetylcholine (Ach)

Question 14

Where are calcium ions stored in the muscle?

Answer 14

The sarcoplasmic reticulum

Question 15

What is the relationship between control and muscle fibers?

Answer 15

The more precise the control the less muscle fibers are controlled by a motor neuron and vise versa

Question 16

What is muscle hypertrophy?

Answer 16

An increase in muscle mass

Question 17

What is muscle atrophy?

Answer 17

Decrease in muscle mass due to lack of use (Ex. Broken leg, Paralysis, etc)

Question 18

What is muscle tone?

Answer 18

The tension of a relaxed muscle that stabilizes position of bones and joints

Question 19

What are the three types of skeletal muscles?

Answer 19

Fast fibers
Intermediate fibers
Slow fibers

Question 20

What are features of fast fibers?

Answer 20

-Large diameter
-High glycogen reserves
-Few mitochondria
-Anaerobic metabolism
-Fatigue easily
-Powerful contractions
-Lead to hypertrophy

Question 21

Features of slow fibers?

Answer 21

-Small diameter
-Slow acting but long lasting
-Abundant myoglobin
-Use aerobic metabolism
-Large network of capillaries

Question 22

What are the four ways to classify skeletal muscle by arrangement?

Answer 22

-Parallel (Ex. Biceps)
-Convergent (Ex. Pectoralis)
-Pennate (Unipennate, Bipennate, Multipennate)
-Circular (Ex. urethral sphincter)

Question 23

What does Origin mean in muscle terminology?

Answer 23

It’s the point of the muscle that remains stationary

Question 24

What does Insertion mean in muscle terminology?

Answer 24

The point of the muscle attachment that’s moveable

Question 25

What does Action mean in muscle terminology?

Answer 25

The function of the muscle upon contraction

Question 26

What are the 4 types of primary actions of muscles?

Answer 26

-Prime movers (Agonists) (Responsible for producing a particular movement)
-Antagonists (Oppose agonist)
-Synergists (Assist the prime mover)
-Fixators (Hold bone in place)