Locomotion on land Flashcards
What is the structure of voluntary, skeletal muscle in mammals and how is it controlled ?
The muscle is striated and is controlled by motor neurones.
How are fibers structured and how do they orientate with the muscle ?
The fibers are grouped into fascicles. The fibers can run pennate or parallel to the muscle.
What is the difference in strength when comparing pennate and parallel muscle ?
Pennate muscles are stronger but less maneuverable.
What are the two types of muscular contraction in skeletal muscles in mammals ?
Isometric- Tension is developed but the muscles do not change in length.
Isotonic- Contraction causes the muscle to shorten
What is the equation for work done ?
Work done (J) = Force (N) x Distance (M)
At what contraction speed are mammal muscles most efficient ?
At a third of their maximum.
What are the two types of muscle fibers and how are they different ?
Tonic = slow contraction, rich in myoglobin, require little energy
Phasic fibers= Produce twitch response
What are the three types of phasic fibers ?
Slow phasic- Repeat contraction with no fatigue, high myoglobin, high mitochondria Fast phasic (oxidative)- Fatigue resistant Fast phasic (glycolytic)- rapid fatigue
Why is the relative cost of locomotion larger in small 4 legged animals than large ?
Larger animals will take longer strides due to longer legs, therefore the frequency of strides is much lower. The lower frequency means that there are fewer start stops and slower muscle contraction.
What are tendons made of and how do they aid in running ?
Tendons are made from collagen. They store elastic energy which can be converted to kinetic. e.g achilles tendon convert with 93% efficiency.
What is the pentapedal shuffle in kangaroos ?
This is where kangaroos use their tail as a fifth limb.
What is the pattern for quadrupedal walking.
Always three limbs on the ground at one time. R. Fore > L. Hind > L. Fore > R. Hind. Each foot is on the ground for over half of the time.
What are the three other quadrupedal gaits and how do they occur ?
Trotting- Feet move in diagonal pairs
Pacing- Legs on the same side move together (Used in mammals whose legs are long and risk being tripped when trotting)
Canters and Gallops - Fore feet and hind feet basically move together.
How does galloping help increase speed ?
Due to the fore limbs moving together the back can flex midstride, meaning the stride length is higher and therefore the speed can be higher.
Why are felines the fastest animals on earth ?
They have very flexible spines
