Lectures 12 & 13: Histology: Tissues, Epithelium, and Glands Flashcards Preview

SMP - MCP Exam 1 > Lectures 12 & 13: Histology: Tissues, Epithelium, and Glands > Flashcards

Flashcards in Lectures 12 & 13: Histology: Tissues, Epithelium, and Glands Deck (89):
1

How was the meter defined?

10-7 distance from the equator to the north pole

2

What is the smallest unit of measure the eye can see

1 mm

3

How big is an RBC?

7-9 micrometers in diameter

4

How thick is the plasma membrane?

7.5-10 nanometers thick 

 

5

What is an angstrom?

10-10 meters

6

By how much does the eye fixture of an LM usually magnify the sample?

x10

7

What part of the LM can make the magnification vary?

The objective lenses

8

What is the equation to calculate the resolution of the LM?

Resolution = wavelength x 0.61 / numerical aperture

9

How does the aperture affect the resolution?

The larger the aperture, the worse the resolution (more blurry)

10

What is the resolution of LM?

0.2 microns

11

What is the magnification of LM?

x1,500

12

What is the definition of resolution?

The ability to distinguish 2 pts that are close together

13

Explain how the TEM works

1. Heat up cathode

2. Electrons come up through the cathode and accelerate towards the anode (+ charged)

3. E- go through the anode hole

4. The sample deflects or absorbs the beam and the beam of e-s goes through sections of a thin grid on which the sample is held

5. Beam is reflected on a fluorescent screen releasing photons by different lenses 

Whole unit is in a very high vacuum

 

14

What replaces the LM objective lenses in the TEM?

The objective lens, the intermediate lens, and the projector lens

15

What is the resolution of TEM?

1-1.45 nm

16

What is the magnification of TEM?

x500,000

17

Describe how SEM works

Similar to TEM: cathode that releases e- when heated (thermyonic emission) towards an anode and passes through electromagnbetic lenses that focus beam on sample. Instead of going through the sample, the beam causes the sample to emit secondary and reflected electrons. It scans the surface but does not go through like in the TEM and as it scans, there is another beam pointing down and you can a 3D image of the surface topography of the sample 

18

What is the resolution of SEM?

2 nm

19

What is the magnification of SEM?

x100,000

20

Cell? Microscope?

Q image thumb

RBC

LM

21

Microscope?

Q image thumb

TEM

 

22

Cell? Microscope?

Q image thumb

SEM

23

Cell? Microscope? Stain?

Q image thumb

Kidney

LM

H&E

24

Cell? Microscope? Blue arrows? Black arrows? Dark black?

Q image thumb

Kidney

TEM

Cilia

Mitochondria

Dark black: lysosomes

25

Cell? Microscope?

Q image thumb

Kidney

SEM

26

What kind of prep needed for LM?

1. Fixation (w/ formaldehyde) and dehydration

2. Embedding (wax or plastic)

3. Sectioning (5-10 microns thick) with microtone and steel knives

4. Mounting and staining

 

27

What microscopes require dehydration of samples? Why? What is water replaced with?

ALL

LM and TEM because the samples are embedded in plastic or wax which are not miscible with water

SEM because of vacuum environment

Replaced with organic solvent

28

What is another term for LM?

Brightfield microscopy

29

What are the 5 common LM stains? Describe each

1. Hematoxylin and eosin (H&E): H stains (-) charged and is basophilic and E stains (+) and is eosinophilic

2. Periodic Acid - Schiff: stains carbs 

3. Aldehyde Fuchsin: stains elastic fibers and b-cells of the pancreatic islets

4. Orcein: stains elastic fibers

5. Silver: stains reticular fibers (collagen)

30

What does PAS stain?

Carbs

31

What does H&E stain?

H: nuclei

E: cytoplasm

32

Cell? Microscope? Small arrows?

Q image thumb

Trachea

LM

Small: bleached mucus glands due to dehydration (w/ cilia on the surfaces)

 

33

Cell? Microscope? Arrows?

Q image thumb

Trachea (with cilia)

TEM

Arrows: liquid preserved in the glands 

34

Difference between cilia and microvilia?

Microvilia are much smaller

35

Cell? Microscope? Stain? A? F? D?

Q image thumb

LM

Intestine cell

PAS

a: glycocalyx

f: mucins

d: lymphocytes 

36

Stain? Cell? Microscope?

Q image thumb

LM

Silver

Golgi

37

What prepartion is needed for TEM?

1. Fixation (with osmium tetroxide that preserves lipid) and dehydration

2. Embedding in beam capsules

3. Polymerization of capsules in oven

4. Remove sample from mold

5. Trim for ultrathin sectioning with diamong or glass knives

6. Sample collected on grids (many different types) in a boat of water

7. Staining to impart different electron density with heavy metals (lead and uranium salts) to different parts of the cell

 

38

How is the fixation process different in LM and TEM?

LM: wax or plastic, thicker

TEM: only plastic, thinner, more sophisticated

39

Microscope?

Q image thumb

TEM

40

A? B?

Q image thumb

A: microvilli labelled with gold particles

B: aquaporins

41

What is freeze fractioning?

Another EM technique where we fracture the cell through the middle of the bilayer and expose the proteins embedded in the membrane (E and P faces)

42

What is the prep needed for SEM?

1. Fixation & dehydration (because it goes in a vacuum)

2. Coat it to accentuate the release of e-s from sample

THAT'S IT!!

43

Which microscope requires the least prep?

SEM

44

What is this?

Q image thumb

Cilia on trachea (goblet cells)

45

Electron beam different in SEM and TEM?

Nope

46

Same fixation process in LM and TEM?

Nope

47

At the LM level can you see ribosomes? Microtubule? Microfilament? Basal body?

No

No

No

YES!

48

What are 8 characteristics of epithelial cells?

1. Cover/Line all surfaces in the body except for joint cavities

2. Lie on basal lamina of the basal membrane

3. Avascular

4. Polarity: apical and basolateral portions

5. Keratin filaments provide strength and desmosomes makes them act like a continuous sheet

6. Many have remarkable renewal capacity (like skin and intestines)

7. Derived from 3 germ layers: mesoderm, ectoderm, endoderm

8. Diversity in function: secretory, protective, absorptive

49

Do epithelial cells have veins?

NOPE

50

How do you distinguish the basement membrane from the basement lamina?

Membrane: you can see with LM

Lamina: EM level

51

What are surface epithelia classified by? 

1. # of cells in epithelium: simple/stratified

2. Height and shape of surface layer of cells: squamous/cuboidal/columnar

52

Simple squamous epithelium: shape? what do they line? shape of nuclei?

Flat

Body cavities, blood vessels

Round nuclei

53

Simple cuboidal epithelium: shape? shape of nuclei?

Cube

Flattened nuclei 

54

Simple columnar epithelium: shape? shape of nuclei?

Tall 

Eliptical nuclei

55

Type of epithelial cell?

Q image thumb

Simple squamous

Blood vessel!!

56

Type of epythelial cell? Where?

Q image thumb

Simple cuboidal

Kidney collecting duct

57

Why does the nuclei seem to be missing on certain cells?

Not part of the cut plane in sample

58

Type of epithelial cell? Where?

Q image thumb

Simple columnar

Small intestine

59

What are the stratified epithelium cells named based on?

The surface cells

60

What are the 3 types of stratified epithelium? Describe each

1. Stratified squamous/cuboidal/columnar

2. Ciliated pseudostratified: not actually stratified but nuclei are at different levels

3. Transitional: dome shaped (very unique) which can squeeze and slide over each other

61

Where are transitional epithelium cells found?

Urinary passages: ureter, bladder (what brings urine from kidneys to bladder)

62

Type of epithelial cell? Where?

Q image thumb

Stratified squamous (nonkeratinized)

Esophagus

63

Type of epithelial cell? Where?

Q image thumb

Stratified squamous keratinized

Thin skin

64

Type of epithelial cell? Where? What is the pink?

Q image thumb

Stratified squamous keratinized

Thick skin

Pink: epidermis 

65

Type of epithelial cell? Where?

Q image thumb

Stratified cuboidal

Sweat gland duct

66

Type of epithelial cell? Where?

Q image thumb

Stratified columnar

Salivary gland duct

67

Type of epithelial cell? Where?

Q image thumb

Pseudostratified 

Trachea (and all respitatory passages)

68

Type of epithelial cell? Where? Arrow?

Q image thumb

Transitional

Bladder

Binucleation (common for transitional epithelial cells)

69

What are glandular epithelia specialized for? 2 types? Main one?

Secretion

1. Parenchyma: secretory cells of the gland (main type)

2. Stroma: connective tissue in glands supporting the parenchyma

70

What are the 2 main types of glands?

1. Endocrine: secretory product passes directly into blood

2. Exocrine: have ducts to convey product to surface of body or cavity or hollow organ

71

How do we classify the different types of exocrine glands?

1. Shape: tubular (coiled or branched) or acinar 

2. Compound (branching ducts)/Simple (only one duct)

 

72

How can we categorize all glands regarding their secretion?

1. Type of secretion:

(a) Serous: watery secretion: acinar, stained, nuclei are round and located in center

(b) Mucous: viscous secretion: cytoplasm is bleached out during histo so you cannot stain it (appears clear), cuboidal cells w/ flat nuclei

2. Mode of secretion: 

(a) Merocrine (most): product release w/o loss of membrane

(b) Apocrine: whole apical portion of cell is the product 

(c) Holocrine: whole cell is the product

 

73

What do you call the serous glands when connected to mucous glands?

Serous demilune

74

What is the mode of secretion of mammory glands?

Apocrine

75

What is the mode of secretion of sebaceous glands (skin: oily)?

Holocrine

76

Black arrows? White arrows?

Q image thumb

Microvilli brush border

Lymphocytes

77

What are these? Where? What microscope?

Q image thumb

Microvilli

Small intestine

SEM

78

Each line?

Q image thumb

Left to right:

Filaments

Terminal web

Microvilli

Cell coat

79

Arrows?

Q image thumb

Left to right:

Microvilli

Microfilaments

Cell coat (bottom)

80

Black? Blue?

Q image thumb

Cilia

Basal bodies

81

Arrow? Yellow? Microscope?

Q image thumb

Cilia (also very small microvilli above goblet)

Basal bodies

TEM

82

What is this?

Q image thumb

Cilia

83

What is this? Where? Microscope?

Q image thumb

Stereocilia in ductus epididymis

LM

84

What is this? Where? Microscope?

Q image thumb

Stereocilia

Ductus epididymis

SEM

85

What is this? Where? Microscope?

Q image thumb

Stereocilia

Ductus epididymis

TEM

86

What is this? What do they do?

Q image thumb

Microplicae: folds in surface of non keratenized squamous epithelium

Found in oral cavity vagina, anal canal, under the eye

Hold a layer of mucin to protect surfaces from trauma 

87

What microscope needed to see the ER?

EM

88

What can you stain cells that have a cytoplasm rich in ribosomes?

Basophilic dyes (like hematoxylin) because RNA is extremely basophilic

89

What is immunohistochemistry? 2 types?

Specific substances are stained in sections by the use of antibodies that are linked to a fluorescent compound or to an enzyme that can give rise to a colored precipitate in presence of a specific substrate

1. Direct method: primary antibody is labeled

2. Indirect method: second antibody directed toward the first is used to amplify the rxn