Histology

Question 1

are skeletal muscles:

• non-/striated
• un/branched
• single/multinucleated

Answer 1

striated
unbranched
multinucleated

Question 2

where are the nuclei in skeletal muscle

Answer 2

periphery, just under sarcolemma

Question 3

what is a fasicle and how many are in one muscle

Answer 3

bundles of muscle fibres, many

Question 4

epimysium

Answer 4

connective tissue surrounding the whole muscle

Question 5

perimysium

Answer 5

connective tissue surrounding one fasicle

Question 6

endomysium

Answer 6

connective tissue surrounding a single muscle fibre

Question 7

what else do muscles contain

Answer 7

blood vessels, connective tissue, nerves and lymphatics

Question 8

how many myofibrils are in one muscle and what are they composed of

Answer 8

many, sarcomeres

Question 9

what gives the appearance of striations

Answer 9

the Z-discs of adjacent sarcomeres are aligned with one another as are the alternating light and dark bands giving the appearance of striations

Question 10

what does a motor unit consist of

Answer 10

a motor neurone and all the muscle fibres it innervates

Question 11

the less/more of the muscle fibres in a motor unit the finer the control

Answer 11

less

Question 12

what does each branch of a motor neurone end in

Answer 12

neuromuscular junction

Question 13

what is the speed of contraction of type I muscle fibres and what do they depend on

Answer 13

slow, oxidative metabolism

Question 14

describe type I muscle fibre’s resistance to fatigue and their force

Answer 14

resistant to fatigue, loss force

Question 15

what are abundant in type I muscle fibres but not in type IIb

Answer 15

mitochondria and myoglobin

Question 16

what is the speed of contraction of type IIa muscle fibres and what is their resistance to fatigue

Answer 16

relatively fast and reasonably resistant to fatigue

Question 17

what is the speed of contraction of type IIb muscle fibres and what do they depend on

Answer 17

fast, anaerobic metabolism

Question 18

describe type IIb muscle fibre’s resistance to fatigue and their force

Answer 18

fatigue easily, produce greater force

Question 19

what are (a) type I (b) type IIb muscle fibres also called

Answer 19

(a) red fibres (b) white fibres

Question 20

how do cartilage cells get nutrients

Answer 20

diffusion across ECM

Question 21

how do bone cells get nutrients

Answer 21

blood vessels that pervade tissue

Question 22

which of cartilage or bone is permeable

Answer 22

cartilage

Question 23

where are chondrocytes found

Answer 23

in the lacunae of ECM in cartilage

Question 24

function of chondrocytes

Answer 24

secrete and maintain ECM

Question 25

what is ECM composed of

Answer 25

75% water 25% organic material - type II collagen - proteoglycan aggregates

Question 26

what does the type II collagen form in the ECM

Answer 26

3D meshwork

Question 27

what are the 3 types of cartilage

Answer 27

hyaline, elastic, fibrocartilage

Question 28

describe the appearance of hyaline cartilage

Answer 28

blue-white and translucent

Question 29

what is the most common form of cartilage

Answer 29

hyaline

Question 30

what type of cartilage is ECM

Answer 30

hyaline

Question 31

describe the appearance of elastic cartilage

Answer 31

yellow

Question 32

features of elastic cartilage

Answer 32

flexible due to adhesion of elastic fibres

Question 33

describe the makeup fibrocartilage

Answer 33

hybrid between a tendon and hyaline cartilage, dense type I collagen bands interweaved with rows of chondrocytes surrounded by a small amount of cartiligenous ECM

Question 34

functions of bone

Answer 34

support, levers for movement, protection, calcium store, haemopoiesis

Question 35

describe the changes in haemopoiesis throughout life

Answer 35

begins before birth and is main site by birth, by early 20s only the axial and limb-girdle skeleton is involved .

Question 36

composition of bone

Answer 36

bioapatite (calcium phosphate), water, collagen, non-collagen proteins

Question 37

2 types of bone

Answer 37

dense cortical outer bone making up diaphysis | cancellous or trabecular bone at epiphyses

Question 38

describe cancellous bone

Answer 38

fine meshwork

Question 39

what is the difference between compact and cancellous bone

Answer 39

presence of marrow cavities adjacent to cancellous bone but both are lamellar

Question 40

where are cement lines found

Answer 40

in osteons formed during remodelling

Question 41

what cells are in bone types of bone

Answer 41

osteocytes

Question 42

what canals are in compact bone and what is present in them

Answer 42

Haversian | blood vessels

Question 43

how do osteocytes survive in trabecular bone

Answer 43

struts are thin, contact with marrow spaces

Question 44

osteoprogenitor cells, location and function

Answer 44

located on bone surface, pool of reserve osteoblasts q

Question 45

osteoblasts, location, function and prominent organelles

Answer 45

located on surface of developing bone, form bone and have plentiful RER and mitochondria

Question 46

osteocytes, cell type and funtion

Answer 46

bone cell trapped within bone matrix

Question 47

osteoclasts, descroption, location and function

Answer 47

large and multi-nucleated, bone surface and bone resorption

Question 48

how does bone remodelling occur

Answer 48

osteoclasts will congregate and drill into bone, forming a tunnel blood vessels grow into the tunnel bringing osteoblasts with them, these line the tunnel and lay down new lamellar bone process continues until only the space of a Haversian Canal remains

Question 49

what is a basic multicellular unit (BMU)

Answer 49

collection of osteoclasts and osteoblasts

Question 50

what do osteoblasts secrete

Answer 50

collagen, GAGs, proteoglycans and other organic components of the matrix - osteoid

Question 51

describe bone mineralisation

Answer 51

osteoid secreted by osteoblasts mineralise over time in the extracellular space

Question 52

what is the mineral of bone made up of

Answer 52

calcium phosphate crystals (especially hydroxyapatite)

Question 53

what cells are osteoclasts derived from

Answer 53

macrophages

Question 54

how is bone laid down after a break

Answer 54

in a haphazard fashion into woven bone

Question 55

how and why is woven bone remodelled to lamellar vone

Answer 55

it is broken down by osteoclasts and reformed by osteoblasts as it is not as strong