topic 9 - locomotion Flashcards

Question

how does mass affect mass specific MR

Answer 1

higher in smaller large organisms have longer muscles small organisms have shorter muscles more expensive to contract short muscles (less force generated)

Answer 2

As velocity increases, limbs move faster - muscles contract faster - more energy required small have to work harder to run fast - limbs / muscles are shorter - stride is shorter so more contact with the ground (need to overcome gravity each time) as velocity increases, more energy can go towards generateing forward motion - momentum increases - less contact with ground = less energy loss

Answer 3

msMRmax increases linearly for both small and large small organisms have greater msMR max than larger organisms COT decreases linearly for both runners because inertia, momentum, and contact with ground decreases smaller organisms have a steeper increase in MRmax with velocity and higher overall

Answer 4

CoT at a velocity as the slope from the origin to the point of an msMR by velocity plot velocity stays the same when converting (x value) divide y/x to get CoT value (divide msMR by velocity at that point)

Answer 5

negative scaling relationship larger mass = lower CoT for running

Answer 6

gravity - negligible factor in activity budget - big thing that differentiates flying, swimming, and running thrust - energy needed for forward motion - body shape is often adapted to minimise drag buoyancy - generate neutral buoyancy (swim bladders) drag - biggest cost to a swimmer, density / viscosity of water is greater than air

Answer 7

skin friction drag (water has high cohesive properties) higher in small swimmers (single celled organisms) high SA to volume ratio means that a lot of water sticks to surface and being small means less mass and therefore less ability to generate force to overcome friction

Answer 8

pressure drag higher in larger swimmers (fish+) larger organisms (higher volume) are going to create more turbulence which creates pressures that slow it down

Answer 9

0.25 more SA to volume = more skin friction drag larger volume = more pressure drag

Answer 10

larger swimmers experience less skin friction drag (lower SA to volume ratio) small swimmers must work harder to move faster (shorter muscles)

Answer 11

as velocity increases, muscles contract faster (muscles contract faster, more energy required) as velocity increases, pressure drag increases (energy expense rises sharply with velocity to fight pressure drag)

Answer 12

larger = lower cost benefit from larger muscles, ability to generate more force, and lower skin friction drag

Answer 13

curve (U shape) CoT at lowest point at an intermediate velocity

Answer 14

inertial forces are negligible never go fast enough to generate pressure drag different shapes help them catch currents

Answer 15

Gravity - more important at low velocities - effect between runners and fliers Thrust - energy needed for forward motion Drag - more important at high velocities - increases as speed increases Lift - force generated that counters gravity that increases with velocity

Answer 16

Larger fliers fight harder (greater mass) Very small fliers (insects) affected much less (very low mass) Mass is very important for fliers (runway for canada geese vs insects being able to fly immediately)

Answer 17

Very small fliers “swim” through air due to higher relative density / viscosity Larger fliers must work harder to overcome drag Skin friction factors come into play

Answer 18

As velocity increases, limbs move faster Muscles contract faster, more energy required very small fliers have to work hard to move fast - continually beat wings to stay aloft

Answer 19

as velocity increases, both lift and drag increase energy expense to fight gravity decreases but energy expense to fight drag increases drag becomes a tradeoff with gravity

Answer 20

induced power = energy required to counter gravity (decreases at high velocity) parasite power = energy required to counter drag (increases at high velocity)

Answer 21

where induced and parasite power slopes cross

Answer 22

CoT minimsed at intermediate velocities smaller flier = more energy overall than a larger flier

Answer 23

runner = higher CoT flyer swimmer = lower CoT

Answer 24

due to relative importance of gravity negligible in swimmers (buoyancy overcomes) fliers generate lift to overcome gravity (intermediate effect) runners fight gravity with every step