Motility

Falling- decreasing altitudes under gravity, no specializations for producing drag or lift- quickest way of escape for many animals

Parachuting- vertical displacement under gravity, specializations for increasing drag, minimize terminal velocity to slow down

• Gliding- lift generated without flapping, propulsion by jumping and gravity
• “flying lemur”, “flying” squirell, “flying” snake, Alsomitra macrocarpa seed- low
• terminal velocity

Flying- lift generated by flapping, propulsion by flapping

• Advantages- lots of sacromeres in parallel, no bulge, eg. arthropod leg
• Disadvantages- short escrusion, some force wasted due to fiber orientation
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• A force in the direction perpendicular to traveling
• Can be up or down
• Generating by creating a circulatory force
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• An increase in flow (Ek) results in a decrease in pressure (Ep)
• Force perpendicular to flow-Bernoulli's Effect
• Extension of the law of conservation of energy.
• Potential E in fluids is pressure and kenetic E is movement.
• Can't maintain one if the other changes
• In sponges, water flows over the top creating movement in the body of the sponge.
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• Spring loaded inverted pendulum model or pogo stick model
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• Mechanical E= Potential E + Kenetic E
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• The basic components of efficent terrestrial locomotion.
• A vector has both magnitude and direction.
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• Within a lever system a muscle can not have both a high mechanical advantage and a high velocity ration.
• A muscle with a high mechanical advantage can increase speed by increasing muscle length.
• A muscle with a high velocity ratio can increase force production by increasing cross sectional area.
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• L0/L1
• The lever arms complete their arm movements during the same amount of time. A long lever has a greater displacement and so moves faster than a shorter lever.
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• L1/L0
• The longer the in level with respect to the out level, the higher the mechanical advantage and the more power the muscle can use against its load.
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• product of force and lenght.
• Can change even if L0 and L1 are constant
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• part parallel fibered part pinnate
• a common compromise
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• Advantages- shorten rapidly, large excrusion
• Disadvantages- bulges during contraction, relatively few sacromeres in parallel (low force)
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• Hollow cylindrical elements are strong and light
• ex. arthrod leg segments, light poles, plant stems, vertebrate long bones
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• Abdomonial coelom is a fluid filled space that is pressurized to provide support during lifting to help expel feces. When the force is too high and/or the coelomic wall is too weak stuff comes out... inguinal hernia
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• Build structures with multiple layers to prevent propagation of cracks
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• Use composite materials- one good in compression and one good in tension

• stress-strain relationships of biomaterials are often time dependent
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Strain/stress

stress/strain

The strain imposed on a material at failure

The stress impossed on a material at failure

• Lift production
• The roboseed with samara from maple tree - spins around and chops air creating lift.
• Form of natural selection to carry it away from the parent tree.
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• High kenetic energy on top and less pressure on the bottom pushing it up.
• Happens in curve balls and sail boats
• Snapping shrimp claps. Gasses dissolve in water and it makes bubbles then the cavitation slams shut creating a very intense shock wave
• Ailanthus tree (tree of heaven)- seed in the middle falls off the tree ans starts t twirl generating lift by autorotation. The horizontal force moves it away from the shadow of the tree

• Nonrotating object that imposses rotation of air.
• The speed of air increases over the curvator
• As soon as wing tip passes,air circulates and begins circulating in a trail
• Way of generating a magnus effect without spinning
• Occurs in birds and airplanes
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