Muscles Flashcards
1
Q
Cardiac Muscle Characteristics
A
Where: Heart Appearance: Striated Shape: Branching Y Action: Involuntary Nucleus: Uni-Bi Rhythmic: Rhythmic Intercalated Discs: Yes Speed of Contraction: Slow
2
Q
Smooth Muscle Characteristics
A
Where: Visceral (Internal Organs) Appearance: Non-striated Shape: Tapered point Action: Involuntary Nucleus: Uni Rhythmic: Either due to Blood Vessels (related to heart) Intercalated Discs: No Speed of Contraction: Slower
3
Q
Why do muscles have the ability to move?
A
- Contraction
- Irritability
- Extensibility
- Elasticity
4
Q
Connective Tissue Wrappings
A
- Cells are surrounded and bundled by connective tissue
- Endomysium: Enclosing a single muscle fiber
- Perimysium: Wraps around a fascicle (bundle) of muscle fibers
- Epimysium: Covers the entire skeletal muscle
- Fascia: On the outside of the epimysium
5
Q
Sites of Muscle Attachment
A
- Bones
- Cartilages
- Connective Tissue Coverings
6
Q
Skeletal Muscle Functions
A
- Movement
- Posture (Jelly Donut)
- Heat
- Stabilize Joints
7
Q
Sacrolemma
A
-Specialized plasma membrane
8
Q
Myosin Filaments
A
- Thick filaments
- Composed of the protein myosin
- Has ATPase enzymes
- have heads (extensions, or cross bridges)
- Myosin and actin overlap somewhat
9
Q
Actin Filaments
A
- Thin filaments
- Composed of a protein actin
- Anchored to the Z disc
10
Q
Sarcoplasmic Reticulum
A
- Specialized smooth endoplasmic reticulum
- Stores and releases calcium (calcium is important for energy production)
- Surrounds the myofibril
11
Q
Myofibrils
A
- aligned to give distinct bands
- I Band= Light band
- Contains only thin filaments (actin)
- A Band= Dark band
- Contains the entire length of the thick filaments (myosin)
- I Band= Light band
12
Q
Sacromere
A
- Contractile unit of a muscle fiber (z line to z line)
- Organization of the sacromere
- Myofilaments
- Thick filaments= myosin filaments
- Thin filaments= actin filaments
- Myofilaments
13
Q
What Skeletal Muscles need to Contract
A
- Strength of stimuli
- Ca+
- Na+
- Blood flow
- Glucose
- Red Blood Cells
- Oxygen (breaks down sugar)
- Iron (attracts oxygens)
- Phosphate bonds Cp+ ATP
- Number of mitochondria
- K+
14
Q
Graded Responses
A
-different degrees of skeletal muscle shortening
15
Q
How graded responses can be changed
A
- The frequency of muscle stimulation
- The number of muscle cells being stimulated at one time
16
Q
Twitch (Graded Response)
A
- Single, brief contraction
- Not a normal muscle function
17
Q
Tetanus (Type of Graded Response)
A
- Summing of contractions
- One contraction is immediately followed by another
- The muscle does not completely return to a resting state
- The effects are added
18
Q
Unfused Incomplete Tetanus (Graded Response)
A
- Some relaxation occurs between contractions
- The results are summed