Histology And Pathology

Question 1

What is the maximum resolving power of an electron microscope?

Answer 1

0.2 nanometers

Question 2

True or false: all cancers are diagnosed histologically.

Answer 2

True

Question 3

What is involved in tissue preparation for histological examination?

Answer 3

Sections need to be fixed, cut, embedded and stained to be viewed under the microscope.

Question 4

What is avoided by ‘fixing’ tissues? (Fixing structures in place via cross-linking)

Answer 4

Stops tissues from breaking down as when they are removed from the body they are no longer supplied with blood or nutrients.

Question 5

What is the most common fixative and what properties does it have?

Answer 5

Formalin - a powerful antibacterial that can harden tissue.

Question 6

What is the role of paraffin and how is it applied to tissue?

Answer 6

Paraffin stiffens tissues to make them easier to cut. It is not soluble in water and therefore needs to water to be removed by alcohol.

Question 7

What does haematoxylin bind to and what colour does it dye those components?

Answer 7

Binds to acidic or anionic (negatively charged) molecules and dyes them blue ie. Nuclei and some acid microns and proteoglycans.

Question 8

What does eosin dye and what colour is it?

Answer 8

Eosin binds to cationic components such as positively charged amino groups of proteins. Dyes them pink.

Question 9

What type of tissue would stain with both H and E stains (amphophilic)?

Answer 9

The cytoplasm of cells abundant with RER

Question 10

What do inmunohistochemistry stains target?

Answer 10

Antibodies- using specifically targeted antigens.

Question 11

What are the four basic tissue types?

Answer 11

Connective tissue, epithelium, muscle and neural tissue.

Question 12

Name 6 types of specialised connective tissue.

Answer 12

Cartilage, bone, adipose tissue, blood, haemopoietic tissue, and lymphatic tissue.

Question 13

Approximately how much blood does a 70kg person have in their body?

Answer 13

5 litres.

Question 14

Name 5 components of plasma.

Answer 14

Water, protein, salts, lipids, sugar.

Question 15

What are the three main types of protein in plasma?

Answer 15

Proteins involved in coagulation, albumin, and globulins

Question 16

Are neutrophils normally found in healthy tissue?

Answer 16

No.

Question 17

Do mature RBCs have a nucleus or organelles?

Answer 17

No.

Question 18

What is the life span of a RBC?

Answer 18

120 days in blood.

Question 19

What are reticulocytes?

Answer 19

The form in which RBCs are released into the blood.

Question 20

When would there be increased number of reticulocytes in blood?

Answer 20

Following haemorrhage or haemolysis.

Question 21

What is the name of an immature nucleated RBC?

Answer 21

Normoblast

Question 22

What is the lifespan of a platelet?

Answer 22

8-10 days.

Question 23

Name three types of granulocytes.

Answer 23

Neutrophils, basophils, eosinophils.

Question 24

What reactions are eosinophils involved in?

Answer 24

Allergic and parasitic.

Question 25

Where are eosinophils usually found?

Answer 25

In the GIT

Question 26

What disease are basophils important in?

Answer 26

Asthma

Question 27

What do basophilic granules contain?

Answer 27

Histamine.

Question 28

Where does haemopoeisis occur?

Answer 28

Red bone marrow

Question 29

In newborns- all bone marrow is red. Where can red bone marrow be found in adults?

Answer 29

Only the axial skeleton and proximal femurs.

Question 30

Where does fetal haemopoeisis mainly occur?

Answer 30

In the liver.

Question 31

What is the maximal resolving power of a light microscope?

Answer 31

0.2 micrometers

Question 32

Where is epithelia found?

Answer 32

Lining surfaces or as the main cell type of an organ. | Eg. Liver, thyroid, pancreas.

Question 33

Where do the most common cancers arise?

Answer 33

In epithelia; breast, prostate, colon, lung, skin.

Question 34

What must everything that enters or leaves the body pass through?

Answer 34

Epithelium

Question 35

Name 5 examples of surface epithelium

Answer 35

Skin, GIT, respiratory system, kidney, reproductive tract.

Question 36

Name 5 functions of epithelia.

Answer 36

Protection, selective diffusion, absorption, secretion, receptors

Question 37

Name four characteristics of epithelial cells.

Answer 37

Exhibit polarity, connected by cell junctions, supported by a basement membrane, avascular

Question 38

How does epithelium obtain oxygen and nutrients?

Answer 38

Through diffusion from capillaries through BM/connective tissue

Question 39

When naming stratified epithelia, the shape of what layer of cells is important?

Answer 39

The topmost layer.

Question 40

Name 3 characteristics of simple squamous epithelia.

Answer 40

Widely spread cells, flat, nucleus is flat.

Question 41

What is the main function of simple squamous epithelia and what feature allows this function to occur?

Answer 41

Allows easy diffusion as the cells are flat.

Question 42

Give four examples of simple squamous epithelia?

Answer 42

Mesothelium, endothelium, lining of alveoli, glomeruli.

Question 43

Name the main function of simple cuboidal epithelia?

Answer 43

Secretory (easy for substances to move across).

Question 44

Give 2 examples of simple cuboidal epithelia

Answer 44

Renal tubule, thyroid follicles

Question 45

Describe simple columnar epithelia and their functions.

Answer 45

Simple columnar cells are taller than they are wide with the nucleus at the base taking up 1/4-1/3 of the cell. They form a barrier and can have absorptive or secretory functions.

Question 46

Give 5 examples of non-ciliated simple columnar epithelia.

Answer 46

Stomach, small and large intestines, gall bladder and bile ducts, endocervix

Question 47

Name 2 examples of ciliated simple columnar epithelia.

Answer 47

Fallopian tubes, bronchioles.

Question 48

What differentiates pseudostratified columnar epithelium from stratified?

Answer 48

All cells have their base on the basement membrane, even though it may not look like it.

Question 49

Give an example of pseudostratified ciliated columnar epithelium.

Answer 49

Respiratory tract.

Question 50

Give 2 examples of pseudostratified non-ciliated columnar epithelia.

Answer 50

Epididymis and vas deferens.

Question 51

Where would you find stratified squamous epithelia and why?

Answer 51

Found in skin, mouth, anus, vagina, oesophagus where there may be mechanical trauma. This epithelium is very tough. Keratinising in skin.

Question 52

Where would you find stratified cuboidal epithelia? (2)

Answer 52

Ducts- eg. Pancreas and salivary glands.

Question 53

Name 3 contractile epithelia and why they have that property.

Answer 53

Surface columnar layer of epithelium overlying myoepithelial layer results in contraction. Eg. In breast, sweat glands, salivary glands.

Question 54

Describe the epithelium of the prostate.

Answer 54

Surface columnar layer overlying a basal layer.

Question 55

Describe the epithelia at the renal pelvis, ureters and bladder.

Answer 55

Epithelia needs to expand here so surface cells are taller.

Question 56

Can you see individual microvilli in light microscopy?

Answer 56

No. Just a brush border.

Question 57

By what factor do microvilli increase surface area?

Answer 57

20

Question 58

What is the core of cilia made from and where does it attach.

Answer 58

Pairs of microtubules. | Attach to basal body structure.

Question 59

What kind of intercellular junctions do you see between epithelial cells?

Answer 59

Often all three: Zonula occludens (tight junctions) Zonula adherens, Macula adherens (desmosomes)

Question 60

What do right junctions do?

Answer 60

Seal intercellular spaces to block passage of substances between cells. Links cytoskeletons of two cells via actin and the claudins and occludins proteins.

Question 61

What type of junctions are important in the blood-brain barrier?

Answer 61

Tight junctions.

Question 62

What is a hemidesmosome?

Answer 62

A modified desmosome that links epithelial cells to the underlying basement membrane.

Question 63

What are adherens junctions?

Answer 63

Adhering junctions and desmosome a are mechanically strong attachments between cells that link cytoskeletons.

Question 64

What are cadherins? What do they bind to?

Answer 64

Transmembrane proteins- bind to cadherins on other cells.

Question 65

Do desmosome a limit what is passed through?

Answer 65

No.

Question 66

What is a glycoprotein component of connective tissue?

Answer 66

Laminins

Question 67

What are integrins? What do the bind to?

Answer 67

Integrins link to the basement membrane and often link to Laminins.

Question 68

What important molecules for adhering cells together can be manipulate by metastasising cancer cells?

Answer 68

Cadherins/catenins

Question 69

What is an important protein in gap junctions?

Answer 69

Connexin

Question 70

What is the role of gap junctions?

Answer 70

Involved in communication eg. Present in cardiac muscle for spread of action potential and contraction.

Question 71

What junctions are cadherins involved in?

Answer 71

Adherens junctions.

Question 72

What transmembrane Cell Adhesion Molecule (CAM) is involved in cell-ECM interaction.

Answer 72

Integrins.

Question 73

What transmembrane CAMS allow white blood cells to move into tissue?

Answer 73

Selectins

Question 74

Do epithelial cells make components of BM?

Answer 74

Yes. Even components usually made by fibroblasts.

Question 75

What proteins are involved in linking integrins of epithelial cells to ECM?

Answer 75

Laminins and fibronectin.

Question 76

What are the 3 main components of the ECM component of basement membrane?

Answer 76

Collagen IV, heparan sulphate, structural glycoproteins.

Question 77

What type of collagen is involved in attachment if BM to underlying connective tissue.

Answer 77

Collagen VII

Question 78

What are myocytes, adipocytes and Schwann cells surrounded by that is similar to a basement membrane?

Answer 78

Basal lamina

Question 79

Name the 4 functions of BM.

Answer 79

Structural support, controls epithelial growth, links epithelium to underlying tissue, selective barrier to nutrients.

Question 80

Intima is the lining of blood vessels. What is it called in the heart?

Answer 80

Endocardium.