Principles Histology

Question 1

Features of eukaryotes

Answer 1

nucleus, membrane bound organelles, cytoplasm + cytoskeleton, inclusions

Question 2

features of plasmalemma

Answer 2

semi rigid, amphipathic phospholipid bilayer, anchored + laterally moving proteins, cholesterol between tails of lipids, semi permeable

Question 3

Permeable to?

Answer 3

small uncharged molecules e.g. O2, H20

Question 4

define exocytosis + endocytosis

Answer 4

Exo = excretion of materials
Endo = intake of materials

Question 5

Role of cytoskeleton

Answer 5

provide structure and support + allow movement

Question 6

3 filaments involved in cytoskeleton

Answer 6

micro filaments, intermediate filaments, microtubules

Question 7

features of microfilaments

Answer 7

actin filaments, globular, constantly breaking up + reassembling

Question 8

features of Intermediate Filaments

Answer 8

more permanent, mechanical strength, specific to cell type

Question 9

features of microtubules

Answer 9

hollow rods, made of alpha + beta tublin, radiate from centrosome, polar + act as motorway

Question 10

movement along microtubules + carrier compounds involved

Answer 10

Dynein = moving towards cell centre
kinesin = moving away from cell centre

Question 11

Nucleus membrane

Answer 11

bi layered membrane (inner + outer) with perinucleur cistern between

Question 12

Feature of perinuclear cistern

Answer 12

continuation of rough ER (proteins are trapped after being constructed)

Question 13

transcription of m,r+t RNA

Answer 13

m + t RNA transcribed in nucleus, rRNA transcribed in nucleolus

Question 14

2 forms DNA can be found in + definition

Answer 14

heterochromatin = densely packed
Eurochromatin = loosely packed (undergoing transcription)

Question 15

Structure of ribosome

Answer 15

1 large + 1 small sub unit

Question 16

Rough Endoplasmic reticulum

Answer 16

Production of proteins, inner channel is continuation of perinuclear cisterna - captures translated proteins

Question 17

Smooth Endoplasmic reticulum

Answer 17

production of lipids+ fats

Question 18

Golgi Apparatus

Answer 18

modification of proteins e.g. cleavage + addition of sugar

Question 19

features of mitochondria

Answer 19

produce ATP, bi membrane, inner membrane invaginates (cristae)

Question 20

3 types of cell junctions

Answer 20

1) occluding junctions
2) anchoring junctions
3) communicating junctions

Question 21

occluding junctions

Answer 21

links 2 cells together, creates a diffusion barrier, reduces extracellular space, zonula occlusion

Question 22

2 types of anchoring junctions

Answer 22

zonula adherns + desmosome

Question 23

desmosome + zonula adherns

Answer 23

both - transmembrane proteins bind to adjacent cell in extracellular space. desmosome bound to centrosome in cell, zonula adherns bound to cytoskeleton

Question 24

2 main stains used

Answer 24

haematoxylin = bacic die binds to acids (blue) 
eosin = acidic die binds to bases (pink)

Question 25

4 main tissue types

Answer 25

1) epithelium 2) connective tissue 3) Muscle 4) Nervous tissue

Question 26

Uses of epithelium

Answer 26

Line surfaces + hollow organs + glands

Question 27

Features of epithelium

Answer 27

strong junctions between cells, form sheets - small intercellular space, basal lamina keeps them attached, non vascular - nutrients diffuse in via basal lamina, polarized - basal and apical ends

Question 28

3 types of epithelium

Answer 28

squamous - flat cuboidal - cube columnar - rectangular

Question 29

3 arrangements of epithelium

Answer 29

simple - 1 cell thick layer stratified - multiple layers pseudostratified - appears as many but all attached to basal lamina

Question 30

2 types of glands + specifications

Answer 30

endocrine - basal excretion, into blood stream | exocrine - apical excretion into duct

Question 31

3 types of connective tissue

Answer 31

1) soft CT 2) hard CT 3) blood and lymph

Question 32

features of CT

Answer 32

greater extracellular matrix, made up of cell type and extra cellular matrix

Question 33

Extracellular matrix components

Answer 33

1) Fibres - collaged, elastic + reticular fibres | 2) ground surface - amorphous space filler, made of glycoproteins (GAG's + protein cores)

Question 34

4 cell types in CT

Answer 34

fibroblast = extracellular matrix producer Adipose cells = fat cells Osteocytes = bone cells Chondrocytes = cartilage cells

Question 35

2 types of soft ct + difference

Answer 35

loose + dense. Loose = loosely packed elastic fibres Dense packed

Question 36

2 forms of soft dense CT

Answer 36

regular - all aligned e.g. tendon | irregular - randomly aligned e.g. dermis

Question 37

2 types of hard ct

Answer 37

cartilage + bone

Question 38

3 types of cartilage + how they differ + features

Answer 38

1) Hyaline 2) elastic 3) fibrocartilage - type depends on matrix + chondrocytes - avascular, diffuses in through matrix

Question 39

Bone features

Answer 39

osteocytes + matrix | haversian canal - cannals for neurones + blood vessels

Question 40

2 layers of bone

Answer 40

cortical (outer) | cancellous (inner)

Question 41

3 types of muscle

Answer 41

smooth, skeletal + cardiac

Question 42

features of smooth muscle

Answer 42

non striated, visceral, elongated fibres (cigar shaped)

Question 43

Skeletal features

Answer 43

striated, multinucleated (in sarcolemma)

Question 44

Cardiac muscle

Answer 44

striated to lesser extent, tight junctions + communicating junctions, single nucleated

Question 45

2 types of nervous tissue

Answer 45

neurone + glia

Question 46

protective layers of CNS + PNS

Answer 46

``` CNS = meninges PNS = Epineurium ```

Question 47

types of neurones

Answer 47

``` bipolar = 1 axon 1 dendrite, multipolar = many dendrites 1 axon, pseudounipolar = one long axon ```

Question 48

3 types of glia in CNS

Answer 48

astrocytes, oligodendrocytes + microglia

Question 49

role of each CNS glia

Answer 49

``` astrocytes = blood brain barrier + ion transport + mechanical support oligodendrocytes = myelin producing microglia = immune surveillance ```

Question 50

glia in PNS + role

Answer 50

schwann cells - myelin producing

Question 51

4 components of digestive tract

Answer 51

1. mucosa 2. sub mucosa 3. muscularis propria 4. serosa

Question 52

3 layers of mucosa + function

Answer 52

epithelium - line the lumen/duct lamina propria - loose connective tissue muscularis mucosa - smooth muscle shape + size of lumen

Question 53

sub mucosa

Answer 53

layer of connective tissue

Question 54

muscularis propria

Answer 54

thick layer of muscle inner layer is circular, outer layer is linear

Question 55

serosa/ adventitia

Answer 55

outer layer of connective tissue, suspends tract/ attaches to organ

Question 56

basal lamina

Answer 56

tissue joining epithelium, very thin, non vascular - nutrients diffuse through to epithelium

Question 57

amphipathic

Answer 57

both polar + non polar regions

Question 58

structure phospholipids adopt

Answer 58

micells