Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Musculoskeletal > Histology > Flashcards

Histology Flashcards

1
Q

what is a eukaryotic cell?

A

a cell with a true nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 3 principal types of muscle?

A
  • skeletal (voluntary)
  • cardiac
  • smooth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what do skeletal muscle cells look like?

A
  • striated
  • unbranched
  • multi-nucleated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

where are nuclei found in a muscle fibre & why?

A

at the periphery of the fibres just under the cep membrane because cells are so stuffed with contractile fibres, the nuclei are pushed to the side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what’s the cell membrane called in a muscle fibre?

A

sarcolemma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what groups are muscle fibres put into?

A

fascicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the connective tissue that surrounds the muscle as a whole called?

A

epimysium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the connective tissue around a single fascicle called?

A

perimysium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the connective tissue around a single muscle fibre called?

A

endomysium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are sarcomeres?

A

the unit of contraction of the muscle cell i.e. the smallest contractile elements in the striated muscle cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how are sarcomeres normally placed in a typical muscle cell?

A

end-to-end to form a myofibril

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how are the myofibrils packed into a muscle fibre?

A

dozens to hundred are packed in like cigarettes in a pack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

which is the thick protein filament?

A

myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

which is the thin protein filament?

A

actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what does a Z disk do?

A

anchors actin filaments from adjacent sarcomeres to bind two sarcomeres together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the A band?

A

the length of a myosin filament, darker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the I line?

A

actin by itself, contraction causes it to get smaller due to sliding action of actin & myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

why is skeletal muscle striated?

A

each sarcomere of a myofibril is held in close registry to the next one so the A, I & Z lines line up & look like stripes across the myofibrils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what does a motor unit consist of?

A

one motor neurone & all of the muscle fibres it innervates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does fewer muscle fibres in a motor unit mean?

A

finer control of movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the neuromuscular junction?

A

a special type of synapse where the axon of the motor neurone branches as it nears its termination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

how are the fibres of a motor unit organised in the muscle?

A

scatters but all of the same fibre type

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

where is the finest control found in the body?

A

in the oculomotor nuerones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

how many times does each muscle fibre meet the motor neurone controlling it?

A

once

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is type 1 skeletal muscle fibre?

A

relatively slowly contracting fibres that depend on oxidative metabolism. Have abundant mitochondria & are resistant to fatigue and produce relatively less force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what are type 1 muscle fibres also often called & why?

A

“red” fibres due to lots of myoglobin in the cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

give an example of where type 1 muscle fibres may be found in the body

A

the back

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what are type 2a skeletal muscle fibres?

A

intermediated between types 1 & 2. Relatively fast contracting but also reasonably resistant to fatigue.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

how common are type 2a skeletal muscle fibres?

A

relatively uncommon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what are type 2b skeletal muscle fibres?

A

fast contracting fibres that depend on aerobic metabolism. Have few mitochondria so fatigue relatively easily & produce greater force.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what are type 2b skeletal muscle fibres sometimes called?

A

“white” fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

where may you find type 2b skeletal muscle fibres in the body?

A

the fingers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is cartilage?

A

Semi-rigid and Deformable
Permeable
Avascular (no blood vessels)

34
Q

how are cartilage cells nourished?

A

by diffusion through the extracellular matrix (outer perichondrium)

35
Q

what is bone?

A

rigid

not permeable

36
Q

how are cells in bone nourished?

A

must be nourished by blood vessels that pervade the tissue

37
Q

what are the cells found in cartilage called?

A

chondrocytes (chondroblasts when immature)

38
Q

where are chondrocytes found?

A

live within a space in the extracellular matrix termed a lacuna

39
Q

what are chondrocytes & what do they do?

A

active cells which not only secrete, but also maintain the extracellular matrix around them

40
Q

what is the most common form of cartilage?

A

hyaline

41
Q

what is the composition of the extracellular matrix of hyaline cartilage?

A
  • 75% water

- 25% organic material

42
Q

what is the organic material found in the ECM of hyaline cartilage made up of?

A
  • 60% type 2 collagen

- 40% proteoglycan aggregates

43
Q

what is type 2 collagen?

A

finer than type 1 collagen & forms a 3-D meshowrok

44
Q

what is type 1 collagen?

A

common form found in most connective tissues (e.g. tendon) which aggregates into linear bundles

45
Q

what are proteoglycans made up of?

A

GAGs bound to a core protein & often linked to hyaluronan

46
Q

what are GAGs?

A

most commonly keratin sulfate & chondroitin sulfate

47
Q

what does hyaline cartilage look like?

A

blue-white colour & transluscent

48
Q

what does elastic cartilage?

A

light yellow in colour

49
Q

what gives elastic cartilage it’s flexibility?

A

the addition of elastic fibres

50
Q

what is fibrocartilage?

A

hybrid between tendon & hyaline cartilage

51
Q

what is fibrocartilage made up of?

A

bands of densely packed type 1 collagen interleaved with rows of chondrocytes surrounded by small amounts of cartilaginous ECM

52
Q

what does fibrocartilage look like?

A

white

53
Q

what are the functions of bone?

A
  • support
  • levers for movement
  • protection
  • Ca++ storage
  • Haemopoiesis
54
Q

what is haemopoiesis?

A

blood cell production

55
Q

what are the two types of bone identifiable with the naked eye in a long bone?

A

cortical & cancellous/trabecular bone

56
Q

what is cortical bone?

A

an outer dense shell which makes up the shaft of a long bone

57
Q

where is cancellous bone found?

A

occupies the ends of the bone (epiphyses)

58
Q

what does cancellous bone look like?

A

fine meshwork of bone

59
Q

what is a aversion canal?

A

canal running along long axis of the bone for blood vessels surround by layer upon layer of bone

60
Q

what are the outer layers of the bone called?

A

outer circumferential lamellae

61
Q

what do the layers of bone represent?

A

changes in the collagen that’s laid down and the way it’s orientated (laid down similarly to plywood)

62
Q

what are the living cells found in bone?

A

osteocytes

63
Q

what are volkman’s canals?

A

run horizontally to deliver blood between the aversion canals

64
Q

how do osteocytes get nutrients & O2?

A

through their dendrites which run in canaliculi & can get O2 & nutrients by being in contact with a blood vessel or another osteocyte’s dendrites

65
Q

what are the lines that are often visible surrounding an osteon called?

A

cement lines

66
Q

what is an osteon?

A

the tree ring ling structures with the aversion canals running in them

67
Q

what are osteoprogenitor cells & where are they found?

A

located on bone surfaces, for example under the periosteum, these cells serve as a pool of reserve osteoblasts (precursors of osteoblasts)

68
Q

what are osteoblasts & where are they found?

A

bone forming cells found the surface of developing bone. Have plentiful RER & prominent mitochondria

69
Q

what are osteocytes & where are they found?

A

a bone cell trapped within the bone matrix

70
Q

what are osteoclasts & where are they found?

A

large multinucleate cells found on the surface of bone, responsible for bone resorption

71
Q

how is a bone remodelled?

A

a number of osteoclasts will congregate & will begin to drill into the bone forming a tunnel where a blood vessel will grow into, bringing with it osteoblasts. Osteoblasts line the tunnel & begin laying down new lamellar bone.

72
Q

what is the collection of osteoclasts & osteoblasts that participate in bone remodelling called?

A

basic multicellular unit (BMU)

73
Q

what are osteoclasts believed to be derived from?

A

the macrophage lineage of cells. Several of these cells will fuse and form a single giant cell.

74
Q

what do osteoclasts secrete to eat away at bone?

A

acids & enzymes

75
Q

what do osteoblasts secrete?

A

a type of organic material, an osteoid, which will attract collagen & minerals to it so it will mineralise & harden over time

76
Q

what can younger osteons do to older osteons?

A

partially obliterate them when they’re forming

77
Q

what bone is found in growing children or following a break?

A

woven bone which will then be remodelled into lamellar bone

78
Q

what is the advantage of woven bone?

A

can be made quickly

79
Q

what is the disadvantage of woven bone?

A

not as strong as lamellar bone

80
Q

how are the collagen fibres arranged in woven bone compared to lamellar bone?

A

woven - haphazard nests

lamellar - carefully designed layers

Musculoskeletal (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions