Human Anatomy Chapter 11

Front 1

The muscular system refers ONLY to what muscle tissue

Back 1

Skeletal muscle
(not cardiac or smooth)

Front 2

lever systems explain...

Back 2

how muscles act with or against each other to bring about movements.

Front 3

A lever is...

Back 3

a rigid bar that moves on a FIXED POINT.

Front 4

the fixed point around which a lever moves is called a

Back 4

Fulcrum

Front 5

What is the applied force on a lever called

Back 5

effort

Front 6

the purpose of applying EFFORT is to move a resistance or..

Back 6

load.

Front 7

In human lever systems, what is the:

-levers?
-fulcrums?
-effort?
-load?

Back 7

Bones

Joints

Muscle contraction

The weight of the body part itself + any other weight.

Front 8

Mechanical ADVANTAGE is characterized as having the load (close/far) from the fulcrum and providing the effort (close/far) from the fulcrum.

Back 8

close, far.

Front 9

What is an example of a mechanical advantage lever system?

Back 9

Car Jack

(when effort is farther from the fulcrum, than is the load, a smaller effort can lift a larger load)

Front 10

Mechanical disadvantage is characterized as having the load (closer/further) from the fulcrum than the effort?

Back 10

Further

Front 11

What is an example of mechanical disadvantage?

Back 11

Carrying a shovel full of dirt.

Front 12

From NOTES: "The operation of skelletal muscles involves...

Back 12

leverage"

Front 13

First class levers

-Analogous name
-relative positions
- Mechanical example
- class example
- mechanical advantage/disadvantage?

Back 13

see-saw levers

Load, Fulcrum, Effort

Scisors

Falling asleep (muscles keep head from falling forward)

Can work under both.

Front 14

Second class levers

-Order of forces
-Mechanical example
-Class example
- Mechanical advantage/disadvantage

Back 14

Fulcrum, Load, Effort

Wheelbarrow

Standing on tip-toes

ALL AT MECHANICAL ADVANTAGE!

Front 15

Second class levers

-Rare/Common
- Advantages
- Disadvantages

Back 15

Very rare in the human body

Stength (Very strong system (Only mechanical advantage)

Speed and motion are sacraficed.

Front 16

Third-class levers

-Order of forces
-Mechanical example
-Class example
-Mechanical
avantage/disadvantage

Back 16

Load, Effort, Fulcrum

Tweezers

Lifting weights around the elbow. (bicep workout)

Mechanical DISadvantage ALWAYS!

Front 17

Third class levers

-Rare/Common
-Strong/Weak

Back 17

The most common of lever systems

Weaker than second class but they have better motion and speed.

Front 18

What are the classes of fassicle arrangement (4)

Back 18

Parallel
Convergent
Pennate
Circular

Front 19

Parallel Fassicles of Muscles

-Arrangement
-Strength/endurance
-example

Back 19

fasicles run along the long axis of the muscle itself.

Not very strong, good endurance

Sartorius, Rectus Abdominus (bicep, sternocleidomastoid)

Front 20

Convergent fassicles

-Arrangement
-Strength/endurance
-examples

Back 20

Have WIDE ORIGINS and NARROW INSERTIONS

Stronger than parallel

Pectoralis major

Front 21

Pennate

-Arrangement
-Strength/endurance
-Example

Back 21

fasicles are short and attach obliquely to a tendon that runs the length of the muscle.

Front 22

Pennate fassicles can be either unipennate, bipennate or multipennate depending on

Back 22

the number of sides in which it attaches to the tendon.

Front 23

Circular Fasicles

-Arrangement
-example

Back 23

Concentric rings around orifice

Obicularis Oculi, Obicularis Ori

Front 24

According to Tillman, circular fassicles are not _________________ b/c _________.

Back 24

Sphincters;

circular fasicles are sphincteral (circular) but NOT classified as sphincters.

Front 25

What is a MAJOR difference between parallel/convergent arrangements and pennate/circular.

Back 25

in parallel/convergent fasicle arrangements the muscles extend the length of the muscle.

Front 26

Skelletal Muscles are FUNCTIONALLY classified into four categories. What are they?

Back 26

Agonists
Antagonists
Synergists
Fixators

Front 27

Agonist

-often called
- a muscle that has the...
-example

Back 27

Primary mover

major responsibility for a specific motion.

Biceps Brachii

Front 28

Antagonist

-often called
- a muscle that has the...
-example

Back 28

"against the leader"

job of opposing or reversing a particular movement.

Triceps Brachii

Front 29

Synergist

-functions

Back 29

1.) To add a little more strength to the agonists.

2.) MORE IMPORTANTLY, to stabilize the movement. Several Agonists articulate in several places and cause unwanted movements. Synergists stop these unwanted movements.

Front 30

Fixators

-Function

Back 30

Fixators are considered a class of synergist that function to hold a bone firmly in place when an agonist acts on it.

Front 31

Muscles can be named according to all of the following:

Back 31

Location
Shape
Size
Direction of fassicles
Location of attachments
Number of origins
Actions

Front 32

Recall that all muscles develop from what embryonic layer

Back 32

mesoderm

Front 33

Musculature of the VISCERAL ORGANS includes both...
This muscle originates from the...

Back 33

skeletal muscle and cardiac muscle.

splanchnic muscles (early gut)

Front 34

Musculature of the PHARNGEAL ARCH MUSCLES develop around the...

Back 34

embryonic pharnyx (from the 4-7th somitomeres.

Front 35

Musculature for the axial muscles develop from

Back 35

myotomes and some somitomeres.

Front 36

Musculature of the limb muscles develops from...

Back 36

the lateral parts of nearby myotomes.