Test 1 - Lecture 1 & 2

Question 1

What are the two items that make up a tissue?

Answer 1

1. cells
2. extracellular matrix (proteins & fibers)

Question 2

What are the 4 basic tissue types?

Answer 2

1. epithelial
2. connective
3. nervous
4. muscle

Question 3

What are the 3 important qualities of tissue?

Answer 3

1. structure
2. function
3. location

Question 4

Where can one find epithelium?

Answer 4

1. covers body surfaces
2. lines cavities
3. makes up glands

Question 5

What are some functions of epithelium?

Answer 5

1. protection
2. containing body fluids
3. absorption & secretion

Question 6

What are the 3 ways of classifying epithelium and the categories within each.

Answer 6

1. number of cells (simple & stratified)
2. cell shape (squamous, cuboidal, columnar)
3. location (endothelium, mesothelium)

Question 7

Endothelium

Answer 7

lining of vascular system

Question 8

Mesothelium

Answer 8

lining of body cavities

Question 9

What is connective tissue?

Answer 9

extracellular matrix

Question 10

What are the functions of connective tissue?

Answer 10

1. mechanical reinforcement
2. immune system functions
3. transportation and diffusion of wastes and nutrients
4. storage of energy

Question 11

What differentiates loose and dense connective tissue?

Answer 11

loose - loosely arranged collagen fibers and cells (most epithelia rests on it)

dense - lots of collagen few cells

Question 12

What are the specialized forms of connective tissue?

Answer 12

1. bone
2. cartilage
3. blood

Question 13

What is the cell of muscle tissue?

Answer 13

myocyte

Question 14

What are the two proteins are in large abundance in cells of muscle tissue?

Answer 14

1. myosin
2. actin

Question 15

How is muscle categorized?

Answer 15

1. striated - voluntary (skeletal & cardiac)
2. smooth - involuntary

Question 16

Describe a neuron/nerve cell

Answer 16

axon, cell body, dendrite

Question 17

What is the CNS?

Answer 17

central nervous system - brain & spinal cord (neuroglial)

Question 18

What is the PNS?

Answer 18

peripheral nervous system - peripheral nerves (Schwann & satellite cells)

Question 19

What are functions of supporting cells in the nervous tissue?

Answer 19

1. separate neurons from each other
2. produce myelin sheath
3. active phagocytosis
4. contribute to the blood brain barrier in CNS

Question 20

What does the term “ganglia” refer?

Answer 20

aggregations of nerve cell bodies in PNS

Question 21

What are the embryonic origins of tissues?

Answer 21

1. ectoderm
2. endoderm
3. mesoderm

Question 22

What are the tissue types that arise from the ectoderm?

Answer 22

surface ectoderm (epidermis and assc. parts such as hair, nail, glands)

neuroectoderm (brain and nervous system)

Question 23

What are the tissue types that arise from the endoderm?

Answer 23

embryonic gut (digestive, liver, pancreas, respiratory)

Question 24

What are the tissue types that arise from the mesoderm?

Answer 24

1. notochord
2. somites (muscle, excretory, glands)
3. mesenchyme (dermis, circulatory, bones, cartilage)

Question 25

What are the 4 main stages of tissue preparation for microscopy?

Answer 25

1. fixation 2. embedding 3. sectioning 4. staining

Question 26

What is an artifact?

Answer 26

an unwanted structure only visible due to an error in the tissue prep and staining process

Question 27

Describe tissue preparation briefly.

Answer 27

1. remove tissue from animal 2. cut tissue into pieces 3. fixation (still has water) 4. dehydration (remove water with increasing amounts of alcohol) 5. embedding in parafin 6. sectioning with microtome 7. rehydrate and dehydrate (remove wax) 8. mount & stain sections on glass slides

Question 28

When considering the fixation process, why should specimens be fixed immediately after they are obtained from the organism?

Answer 28

too take a "snapshot" of the exact moment the tissue was removed

Question 29

What are possible artifacts from fixation and how would they arise?

Answer 29

consistency/quality varies - swelling of cells from too much water and shrinking of the cells from too little water

Question 30

During tissue embedding, why must the sample be completely dehydrated before introducing a wax embedding material like paraffin?

Answer 30

because the paraffin is non-polar and not soluble in water

Question 31

Describe longitudinal, oblique, and transverse sections

Answer 31

1. longitudinal: cut in half 2. oblique: cut at an angle (b/w other 2) 3. transverse: horizontal/cross-section

Question 32

Consider routine H&E staining. Why would tissue be dehydrated and treated with a chemical like Xylene after staining, but before applying a mounting medium?

Answer 32

Because the first stain hematoxylin in water-soluble, so sample needs to be rehydrated and the second stain Eosin is in alcohol and is not water-soluble so must be dehydrated

Question 33

Acidic dyes

Answer 33

carry a net negative charge and react with cations - ex: Eosin (Na+ dye-)(pink)

Question 34

Basic dyes

Answer 34

carry a net positive charge and react with anions - ex: Hematoxylin (Dye+Cl-)(blue)

Question 35

Will H&E stain glycogen or for lipids? Why or why not?

Answer 35

No, lipids have no charge and will not stain with H&E

Question 36

What would you propose to use as a staining procedure(s) for glycogen and for lipids?

Answer 36

permanganate or osmium

Question 37

Briefly describe how immunohistochemistry allows for one to image via microscopy.

Answer 37

1. Localizes a specific protein in a tissue session 2. Diagnostics for tumors 3. Detects infectious disease in tissues

Question 38

What is Fluorescence In Situ Hybridization, and where is it useful?

Answer 38

fluorescent dyes + nucleotide probes - making it possible to visualize multiple probes at a time for genetic testing

Question 39

When would an electron microscope be needed (instead of light microscope)?

Answer 39

increases resolution by a factor of 10^3

Question 40

Where is a phase contrast microscope useful?

Answer 40

living cells & tissues

Question 41

Where is a dark field microscope useful?

Answer 41

urine crystals, spirochetes, syphilis

Question 42

Where is a UV Microscope useful?

Answer 42

nucleic acids (specifically purine & pyrimidine bases of nucleotides), proteins that contain certain amino acids, and determine amount of DNA/RNA in certain cells

Question 43

What is useful about confocal microscopy?

Answer 43

allows visualization of specimens in 3D

Question 44

What is atomic microscopy?

Answer 44

used for studying surface topography at molecular & atomic resolutions - nonoptical microscope - works like a fingertip - great for living cells & surroundings environment (doesn't have to be in a vacuum but can be in water)