1.4 Muscle and Tendon Flashcards
What are the three types of muscle?
Skeletal, cardiac, smooth
Describe skeletal muscle (4)
multiple peripheral nuclei
voluntary
striated
regular parallel bundles
Describe cardiac muscle (4)
single central nucleus
involuntary
striated
irregular arrangement with intercalculated disks
describe smooth muscle (4)
single nucleus
involutary
no striations
longer contractions
what are striations?
repeating functional units called sarcomeres.
what is force?
the push or pull on an object with mass that causes it to change velocity
work = ? x ?
work = force x distace
what is power?
power is the rate of performing work.
power = ? / ?
power = change in work / change in time.
Describe pennate muscle fibers.
Short fibres at an angle to internal tendon, or aponeurosis.
What is a benefit of shorter muscle fibers?
shorter fibers = shorter contraction distance = economical
What is the effect of short muscle fibres on the Physiological Cross Sectional Area?
short muscle fibres increase the PCSA.
Describe Parallel muscle fibers
Fibres running parallel to the line of pull of the muscle.
What is the effect of having more sarcomeres in a series?
more sarcomeres = greater total muscle fibres shortening = more potential for performing muscle work.
The Booty Man Loves Big Booty
Tendon = Bone to Muscle Ligament = Bone to Bone
What is the size difference between distal and proximal tendons?
Proximal tendons are shorter and fatter, distal tendons are longer.
List 5 roles of tendons.
- minimises distal limv mass
- joints muscle to bone
- elastic energy storage
- energy conversion
- power amplification
Why are animals with long tendons more economical?
tendons store and release elastic energy, so reduce the cost of running at a steady speed.
How do tendons minimise work and maximise power?
Tendons amplify power. Stretched tendons recoil faster than muscles can shorten, which is less work.
