Exam 3 Lecture 6 Flashcards
What % of body weight and volume is Muscle
40%
Sarcomere Anatomy: Microscope
- I band [actin only - either side of Z disc]
- H band [Myosin only]
- Mitochondria
- Transverse Tubule
- Z-Disc
What is a Z-Disc
the 2 ends of each sarcomere [between 2 I bands]
Soleus Muscle Contraction
Slow onset but long,sustained force
CBC: What happens after the Myosin Head pulls the Sarcomeres together/
It loses the ADP molecule and is now stuck b/c no energy to pull it off of the F-site [makes muscles stiff]
Describe Myosin color and thick or thin
Red and Thick
L-T Relationship: New A Fiber
Understretched = Little force produced
Where is glycogen stored
Liver, Skeletal Muscle
What is Tropomyosin in Actin Filaments
Blocks the view of the myosin head trying to bind to the Actin F-sites; must be moved out the way via Ca++ binding to Troponin C
How Achilles Tear is Handled
Cadaver or take 2 ends and overlap/connect them; makes for weaker muscle overall
Type 2 Skeletal Muscle
*Color [and why]
*Speed and duration of contraction
*Myoglobin and Mitochondria
White, b/c lack of myoglobin
fast onset and short contraction
little myoglobin and mitochondria
CBC: By adding Ca++ to “ready to go state”, what happens next
*What happens to a Phosphate during this
Tropomyosin moves out of the way , allowing for the myosin head to attach to the F-sites on Actin Filament
*Phosphate is released
L-T Relationship: C Fiber Stretch
*Length of Sarcomere?
Best case scenario for our muscles; 2 micrometers; best stretch and force combo
How do motor neurons get proteins far away from the nucleus?
They have a railroad track type system to send proteins down the axon
Where is the Achilles attached
Soleus/Gastroc to Calcaneus Bone
Individual Muscle Cell Name
Muscle Fiber
Contraction of Myofibril: What happens to the H band
The H band disappears
What is the basic functional unit of a skeletal muscle
Sarcomere
What is Titin
the elastic connective tissue that anchors actin and myosin together; allows for stretch
Contraction of Myofibril: Does the A band change
No, it stays the same
CBC: What happens after Myosin head is attached to F-site?
Tension in head is used as energy and pulls at F-site to bring Z-discs closer together and slide actin filament to the right [contraction]
Sarcomere Anatomy: Microscope Pt.2
- Z-Disc
- I Band [actin only]
- A band [actin + myosin]
- H band
- Z-Disc
What is Passive Tension?
Applying pressure to tendons to stretch muscle out
Gastrocnemius Muscle Contraction
Right in the middle between Ocular Muscle and Soleus [most muscles fall into this range]