lecture 8 animal

Question 1

hardened support structures can be ..

Answer 1

external, internal, or absent

Question 2

hydrostatic skeleton

Answer 2

fluid held under pressure in a closed body compartment – pressure around fluid is what makes animal feel hard

Question 3

examples of hydrostatic animals

Answer 3

worms, jellyfish, sea anemone

Question 4

endoskeleton

Answer 4

hardened internal skeleton

Question 5

examples of endoskeleton animals

Answer 5

sponges, humans,

Question 6

exoskeleton

Answer 6

hardened external skeleton

Question 7

examples of exoskeleton animals

Answer 7

arthropod cuticles – shrimp, crabs..

Question 8

locomotion with hydrostatic skeleton

Answer 8

peristaltic crawling of earthworms

Question 9

what types of muscles are earthworms composed of to allow crawling motion

Answer 9

longitudinal muscles and circular muscles – also have bristles

Question 10

what do the segments of worm look like when longitudinal muscles are contracted

Answer 10

short and fat

Question 11

what do segments of worm look like when circular muscles are contracted

Answer 11

long skinny

Question 12

run down of how worm moves

Answer 12

head extends out – circular muscle contracting – bristles will grasp ground – bringing body to head longitudinal are contracting squeezing body forward

Question 13

endoskeletons and exoskeletons generate movement using what

Answer 13

muscles attached to the hard parts of a skeleton

Question 14

where is the tricep and bicep connected

Answer 14

Question 15

antagonistic muscles generate..

Answer 15

opposite movements across a joint
- when one contracts the other relaxes (bicep pulls arm bone towards it when contracts – when relaxed and tricep contracts, brings are out)

Question 16

vertebrate skeletal muscle is an excellent example of

Answer 16

hierarchial organization in biological structures

Question 17

hierarchial organization of muscle

Answer 17

skeletal muscle – muscle fibres (each a multinucleated muscle cell) – myofibrils – thin (actin) and thick (myosin) filaments

Question 18

sarcomere

Answer 18

functional unit of contraction – Z lines separate each sarcomere – sarcomeres shorten during muscle contraction

Question 19

myofibrils are composed of

Answer 19

thin actin and thick myosic filaments

Question 20

thin filament

Answer 20

actin – two chains of actin molecules – contain myosin binding sites

Question 21

thick filament

Answer 21

multiple myosin molecules with their head exposed for binding – motor protein can generate movement with ATP

Question 22

where are the thin and thick filaments attached on the sarcomere

Answer 22

tail ends of actin are attached to z line and tail ends on myosin are attached to M line

Question 23

skeletal muscle is an example of what type of muscle

Answer 23

striated muscle

Question 24

what is a striated muslce –

Answer 24

bunch of lines – linear

Question 25

what parts of the sarcomere change during contraction and what paerts do not

Answer 25

sarcomere changes length but thin ad thick filaments stay same size they just overlap and slide past each other

Question 26

muscle contraction cycle step `1

Answer 26

we have our myosin binding sites -- ATP is attached to the myosin head which is at a low configuration meaning its head is not at the right shape/position for binding with the actin myosin binding site

Question 27

muscle contraction cycle step 2

Answer 27

through hhydrolysis ATP will be converted to ADP and inorganic phosphate which will make the myosin head have a high energy configuration -- this means the head is now at a position where it can bind to the myosin binding sites

Question 28

muscle contraction cycle step 3

Answer 28

this cross bridge is formed when the myosin head attaches to the actin filament

Question 29

muscle contraction cycle step 4

Answer 29

the loss of ADP and inorganic phosphate will force the myosin head to retrieve back to its original bent position which forces and pulls the actin filament towards the center of the sarcomere -- this is what causes the contraction -- when ATP is present again cycle will repeat

Question 30

how does the muscle know when to contract

Answer 30

-- the contraction is initiated by motor neurons -- specifically results in the increase of free calcium ions in the myofibrils of muscle cells therough neurotransmitter exchange

Question 31

why do we need calcium for muscle contraction in addition to ATP

Answer 31

the actin filament is not completelty available for myosin heads to bind -- it is wrapped in regtulatory proteins tropomyosin and troponin which block the actin's myosin vbinding sites. -- Ca2+ will bind to the troponin which will unravel the proteins and expose the binding sites to allow binding

Question 32

what is locomotion

Answer 32

active travel from place to place

Question 33

to move, an animal must expend ..

Answer 33

energy to overcome gravity and friction

Question 34

what determines the the force animals have to overcome

Answer 34

the enviornment -- whatever force is dfominant that opposes locomotion has to be overcome

Question 35

land and air dominating force

Answer 35

gravity

Question 36

water dominating force

Answer 36

friction

Question 37

natural selection favours..

Answer 37

adaptations tha treduce energy costs of locomotion

Question 38

adaptations are usually what

Answer 38

anatomical (anatomy based)

Question 39

example of anatomical adaptation

Answer 39

fusiform body shape, springy tendons

Question 40

fusiform body shape adaptation

Answer 40

fish -- tapered at both ends allowing for faster swimming

Question 41

springy tendons shape adaptation

Answer 41

animals that need to jump -- springs reduce energy cxost

Question 42

adaptations can also be

Answer 42

behavioural

Question 43

examples of behavioural adaptations

Answer 43

passive descent in diving animals -- positions themselves so gravity makes them go down instead of them having to use eenrgy to dive,.

Question 44

animals that locomote on land require..

Answer 44

powerful muscles and strong skeletal support to propel themselves and remain upright

Question 45

maintaining ehat is essential for land animals

Answer 45

balance

Question 46

when walking, how many legs do bipedal animals keep on ground

Answer 46

one

Question 47

when walking how many legs to multi-legged animals keep on ground

Answer 47

three

Question 48

when running or hopping..

Answer 48

all legs can leave the ground because momentum keeps body upright

Question 49

adaptations can reduce..

Answer 49

energy expenditure

Question 50

reducing energy expenditure example (kangaroo)

Answer 50

when the tendons stretch as the animals land, they store enrgy in elastic fibres which is released to help the next jump

Question 51

wings of flying animals must generate enpoigh what to overcome gracities downward force

Answer 51

lift -- which can be achieved by the wing shape itself

Question 52

what do flying animals tend to have that help with locomotion in air

Answer 52

birds -- no uninary bladder -- no teeth -- hollow air filled bones - all light weight so they have less weight to carry -- also fusiform body

Question 53

most aquatic animals are reasonably..

Answer 53

buoyant -- naturally float in water due to extra flubber -- fusiform body is adapted to reduce friction/drag