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Flashcards in locomotion Deck (76)
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1
Q

what is movement and locomotion

A

movement and displacement

2
Q

how does movement help us

A
  1. to maintain equilibrium of body
  2. capture food
  3. ingestion,defence and locomotion
  4. peristalsis
  5. pumping of heart
3
Q

types of movements

A

1.amoeboid/psuedopodial: due to the streaming of protoplasm
seen in amoeba,macrophages, wbc,microfilaments
2.cillary movements: surface of cells have small hair like structures. have an oar like movement creating a current
seen in repro(oviduct) and respiratory tracts and paramoecium
3. flagellate: flagella for locomotion as in sperm and protozoa
4.muscular
5.proctosomes(tentacles) in hydra

4
Q

how does locomotion help us

A
to get food
finding shelter
mating
protection from predators
migration
5
Q

where is muscle from

A

specialied tissue fromthe germ layer mesoderm

6
Q

cells that make muscle

A

myocytes

7
Q

no. of muscles in human body

A

639

8
Q

unique properties of muscles

A

contractibility,excitability,extensibility and elasticity

9
Q

weight of muscles

A

40-50%of human body weight

10
Q

biggest muscle in the body

A

gluteus maximus in the butt

11
Q

smallest muscle in the body

A

stapedius in the middle ear

thinner than a cotton thread

12
Q

muscle is covered by a sheath of connective tissue

A

epimysium

protects from friction

13
Q

inside the epimysium, a muscle has many muscle fibres arranged in a bundle called

A

fasciculi

14
Q

what is fasciculi surrounded by

A

perimysium

15
Q

the muscle fibres in the fasciculi

A

parallel to eachother and the the muscle fibres in the fasciculi are surrounded by endomyseium

16
Q

what are muscle bundles bound together by

A

fascia, it lies above and covers the epimysium

17
Q

what is tendon

A

inelastic connective tissue

joins bone to muscle

18
Q

types of muscles

A
  1. skeletal/striped/voluntary
  2. visceral/smooth/involuntary
  3. cardiac
19
Q

striated muscles(14)

A
cylindrical
blunt ends
unbranched
occur in bundles
good blood supply
voluntary
get impulses from cranial and spinal nerves
intercalated disc absent
multinucleated
a good number of mitochondria
abundant myoglobin
deep striation
quick contraction
easily get fatigued

in hindlimbs,forelimbs,bodywall, tongue, pharynx, upper oesophagus

20
Q

smooth muscles (14)

A
these are spindle shaped
tapering ends
unbranched
occur single,in sheets and small bundles
poor blood supply
involuntary
controlled by autonomic nervous system
intercalcated disc absent
uni nucleated
few mitochondria
poor myoglobin
no stripes
slow contractions
no fatigue

NOT ORGANISED PARALLELY they are present in organs

21
Q

cardiac muscles(14)

A
cylindrical
blunt ends
branched fibres
3d network
rich in blood supply
involuntary
under autonomic nervous system
intercalcated discs present
uni nucleated
mitochondria are abundant
abundant myoglobin
faint stripes
rhythamic contractions
never fatigue

only in heart, they are autogenic and myogenic

22
Q

busiest muscle

A

eye

23
Q

number of muscles to smile

A

17

24
Q

muscles in the root hairs

A

goose bumps

25
Q

anatomical unit of muscle

A

muscle fibre

26
Q

what is muscle fibre covered by

A

sarcolemma( a plasma membrane)

27
Q

what does the sarcolemma enclose

A

sarcoplasm which contains many nuclei

28
Q

what do the muscle fibres contain

A

parallely arranged myofibrils

alternate dark and light bands

29
Q

what are formed over the myofibrils

A

t tubules/transverse tubules

30
Q

what is a myofibril made up of

A
2 types of myofilaments
thick myofilament(myosin)
thin myofilament (actin)
31
Q

the endoplasmic reticulum in the sarcoplasm

A

sarcoplasmic reticulum

a storehouse of calcium for muscle contraction

32
Q

the dark band on myofibril

A

A band ( anisotropic band)

33
Q

light band on myofibril

A

I band(isotropic band)

34
Q

the centre of A band

A

a slightly lighter area called the H band or the hensen zone

35
Q

the M line

A

a dark line passing through the H zone

36
Q

centre of I band

A

dark line passing called the Z line

37
Q

the part between two successive z lines

A

sarcomere

38
Q

what is the sarcomere

A

structural and functional unit of a myofibril

39
Q

what does a sarcomere consist of

A

2 half of I bands and 1 whole A band

40
Q

what is the dark A band made of

A

thick myosin and little bit of the thin actin extends into it

41
Q

what is the light I band made of

A

only thin actin

42
Q

what is myoglobin

A

an oxygen and fe binding protein. found mainly in haemoglobin but in muscles it helps in storing oxygen in the muscles

43
Q

structure of myosin

A

the thick myofilament which are made of polymerised protein myosin
monomers of meromyosin make myosin protein
each meromyosin has two parts( globular head with a short arm and tail)
globular head + short arm is the HEAVY MEROMYOSIN
tail is the LIGHT MEROMYOSIN
the globular head is the site for ATP binding and actin . the head also produces ATPase which hydrolysis ATP to produce energy

the myosin molecule forms a tadpole structure. the head and the short arm protrude out of the body and make bridges with actin

44
Q

the appearance of myosin filament

A

thick dark and rough surface due the cross bridges and it is free at both ends.

45
Q

structure of the thin filament(actin)

A

made up of three proteins(actin,tropomyosin,troponin)

actin: the globular protein which is light weighted molecule. it occurs as monomeric g actin and polymeric F actin. in the presence of magnesium ions,the G actin turns to F actin
tropomyosin: a fibrous molecule. two tropomyosin molecules run closely along the entire length of the actin. at the resting phase, it separates the actin and myosin by binding to the myosin-binding site on the actin

it prevents the formation of cross-bridges.

troponin: at regular intervals of tropomyosin. it makes the active binding sites for myosin on actin filament. it is a trimeric protein
1. troponin I: inhibits actin myosin interaction and binds to other components of troponin
2. troponin T : binding site for tropomyocin
3. Troponin C: binding site for calcium

46
Q

appearnce of actin filaments

A

thin, light,smooth due to no cross bridges,free at one end and joined to Z line at other

47
Q

ration of myosin actin

A

myosin< actin
3 myosin surround 1 actin
6 actin surround 1 myosin.

48
Q

what is end plate

A

nuero muscular junction which recieves impulse from the motor neuron and causes depolarization of the skeletal muscle.
the impulse can be electrical,chemical,thermal,mechanical, hormonal

49
Q

who gave mechanism of muscle contraction.

A

sliding filament theory by hugh huxley and jean hanson

50
Q

the sliding filament theory

A

it the theory where the chemical energy from impulses is converted into mechanical energy of muscle contractions
the myosin head always wants to bind with the actin filament, but the actin filament is always bound to tropomyosin and troponin

luckily, the troponin can be bought over by ca ions and ATP

the action potential is generated via the motor neurons from the CNS. the action potential via acetylcholine reaches the sarcolemma.

it then spreads from the sarcolemma to the t tubules. then impulse then stimulates the sarcoplasmic reticulum to release calcium ions into the sarcoplasm

troponin c of the actin binds with the calcium ions and hence change its shape, the shape change causes the troponin t- tropomyosin complex to move away from the actin.

the myosin binding site is free on actin which then causes the globular head of myosin to release ATPase which breaks the ATP to ADP and inorganic phosphate.
it causes the head to stretch and then causes it to bind with actin.

te actin contracts and it moves closer to H line. the MYOSIN DOES NOT MOVE.

with the help of phosphocreatine, ADP turns back to ATP and the actin-myosin link is broken,
the calcium ions move back into the sarcoplasmic reticulum( with the help of calcium binding proteins called calsequestrin), therefore causing actin to come back to its normal state and the actin moves away from the H zone

the enzyme AchE( acetylcholinesterase) causes the breakdown of acetylcholine in the synaptic cleft,therefore killing the impulse.

51
Q

muscle twitch

A

quick isolated contraction of a muscle, to a single stimulus of threshold value.

52
Q

muscle fatigue

A

muscle fatigue is when repeated contraction of the skeletal muscles anaerobically causes accumulation of lactic acid in the muscles.
the glycogen present in the body breaks down anaerobically to produce lactic acid. its accumulation can cause pain and fatigue.
the lactic acid then diffuses into the blood.
4/5th of it is converted back to glycogen and the other 1/5th into carbon dioxide and water (Cori’s cycle)

53
Q

rigor mortis

A

the complete rigidity of the body after death, due to depletion of ATP and phosphocreatine.

54
Q

muscle spasm

A

sudden, involuntary movement in one or more muscles. People may also call it a charley horse or a muscle cramp or twitch.
occur due to stress, dehydration and exercise or tiredness.

55
Q

during a muscle contraction, the muscle can shorten by

A

1/3 to 1/2 of its length

56
Q

red muscle vs white muscle fibres

A

red white

1.smaller diameter larger diameter
2.red due to haem- myoglobin is absent
protein myoglobin
3.more mitochondria less
4.more capillaries less
5.less sarcoplasmic more
reticulum
6. aerobic oxidation anaerobic, collect lactic acid
7. slow long fast short contractions
contractions.

57
Q

where can you find red muscle fibres

A

extensor muscles, flight muscles of kites

58
Q

where can you find white muscle fibres

A

eyeball, flight muscles of a sparrow

59
Q

contraction of smooth muscles

A

slow lasts much longer

troponin absent, they have a protein called calmodulin that binds calcium to the cytosol

60
Q

where do smooth muscles get impulses from

A

autonomic nervous system

61
Q

contraction of cardiac muscles

A

gap junctions allow muscle contraction to spread from one fibre to another.
long refractory period and lactic acid produced is used to make ATP

62
Q

what constitutes the skeletal system

A

bones and cartilage

63
Q

exoskeletal system

A

the skeleton is external. it is made up of dead tissues.

present in both vertebrates and invertebrates

64
Q

endoskeleton

A

present inside the body
made up of cartilage and bones in
vertebrates
present in both vertebrates and invertebrates, to make a framework and protect

65
Q

bones in a child and adult

A

300 and 206 respectively

66
Q

the two skeletal systems in man

A

axial and appendicular

67
Q

axial skeletal system parts

A

total 80

skull 29
vertebral column 26
ribs 24
sternum 1

runs along the middle longitude of body

68
Q

of the 29 skull bones what makes them

A

facial 14
cranium 8
ear ossicles 6
hyoid bone 1

69
Q

cranium

A

frontal(1) anterior part of the skull, forms the forehead

parietal(2) greater portion, the sides and roof of the skull

temporal(2) inferior lateral part, forms part of the cranial floor

occipital(1) posterior part, the base of the cranium

sphenoid(1) middle part holds all the bones of the cranium together. saddle-shaped sella turcica enclosing the pituitary gland

ethmoid(1) sponge-like appearance, located on the midline of the anterior part of cranial floor. the cribiform plate forms the roof of the nasal cavity through which olfactory nerve passes.
perpendicular plate forms the superior portion of the nasal septum.

70
Q

why is the skull called dicondylic

A

due to the presence of two occipital condyles in the skull (occipital bone).The condyles connect the skull with Atlas

71
Q

large opening at the base of the skull through which the spinal cord passes

A

foramen magnum

72
Q

the facial bones

A

nasal bone 2 bridge of the nose

maxillae 2 upper jaw

zygomatic 2 prominences of the cheek

lacrimal 2 thin bone containing lacrimal sac

palatine 2 posterior part of the hard palate and form floor and lateral wall of the nasal cavity

inferior nasal conchae 2 inferior lateral wall of nasal cavity

vomer 1 inferior portion of nasal septum

mandible 1 movable lower jaw, strongest facial bone

73
Q

which bone doesn’t articulate with any other bone

A

hyoid bone

74
Q

backbone

A

the vertebral column, present mid-dorsal region of body

75
Q

invertebral discs

A

present between two adjacent vertebrae, they are pads of cartilage ,provides flexibility

76
Q

the 26 vertebrae

A
cervical 7
thoracic 12
lumbar 5
sacral 1
coccyx 1

in a child, the sacral bones are 5 and coccyx is 4 , therefore total 33 vertebrae. they fuse in adults, therefore 26