Introduction

Question 1

What are cells?

Answer 1

functional units of living organisms

differentiate to perform special functions

Question 2

What are tissues?

Answer 2

cells with similar morphology and/or function

Question 3

What are organs?

Answer 3

anatomically discreet collections of tissues that perform certain functions (liver,kidney)

Question 4

What is parenchyma?

Answer 4

cells that make up the functional elements of an organ

Question 5

What is stroma?

Answer 5

structural framework of an organ, background tissue

Question 6

Tissues and organs are organized into

Answer 6

larger systems - may be discreet entities (CNS) or diffuse aggregates (immune system)

Question 7

What are the five basic tissue types?

Answer 7

blood, connective tissue, epithelium, muscle, and nervous tissue

Question 8

What is blood?

Answer 8

fluid tissue, contained within vessels of circulatory system

Question 9

What is connective tissue?

Answer 9

surrounds and supports other tissue

Question 10

What is epithelium?

Answer 10

covers body surfaces, lines cavities, and forms glands

Question 11

What is muscle?

Answer 11

contains specialized contractile cells responsible for movement

Question 12

What is nervous tissue?

Answer 12

contains modified cells responsible for intercellular communication

Question 13

Tissue preparation

Answer 13

unfixed tissues autolyze/denature
prevent this with fixation in formalin (preserve tissue)
place tissue in cassette
embed in liquid parafin or plastic resin
microtome/grind
mount on slide
remove paraffin
rehdyrate with alcohol and xylene
place coverslip over

Question 14

What is an H&E stain?

Answer 14

hematoxylin - blue basic dye, stains acids (nuclei) = basophilic (purple/blue)
most common

Question 15

What is an eosin stain?

Answer 15

red-pink, acidic dye, stains bases (proteins) = eosinophilic (red-pink)

Question 16

What are the special stains?

Answer 16

gram (bacteria) GMS, and silver stain (fungi)

Question 17

What is another name for the cell membrane? Function?

Answer 17

plasmalemma - functions as semi-permeable membrane

Question 18

What is a common feature of a cell membrane?

Answer 18

phospholipid bilayer (amphoteric and amphipathic) composed of hydrophilic heads and hydrophobic tails

Question 19

What does the hydrophilic portion of cell membranes contain?

Answer 19

charged N groups and charged phosphate groups
present on both inside and outside of membrane

Question 20

What does the hydrophobic portion of cell mebranes contain?

Answer 20

two long chain FA’s covalently linked to glycerol

Question 21

What creates the tri-laminar appearance on the cell membrane EM?

Answer 21

2 electron dense layers (hydrophilic)
1 electron lucent layer (hydrophobic)

Question 22

What is the fluid mosaic model?

Answer 22

fluidity of the membrane increases when temperature increases and decreases with saturation of fatty acids

Question 23

What helps regulate fluidity and stabilizes membranes?

Answer 23

cholesterol
increase cholesterol stiffens membrane and decrease fluidity

Question 24

What is the ratio of cholesterol and phospholipids in the cell membrane?

Answer 24

1:1