HISTOLOGY EXAM 1 QUESTIONS &
ANSWERS
Histology is the study of _______ and ______. - Correct Answers -Cells and tissues
What are the 4 primary tissues? - Correct Answers -Epithelial (squamous, cuboidal,
columnar)
Connective (connective tissue proper, cartilage, bone, blood)
Muscle (skeletal, cardiac, smooth)
Nervous (neurons and neuroglias)
What are 3 processes of preparing cells for study? - Correct Answers -Fixation
- Formalin (37% aqueous solution of formaldehyde)
- Preservation of tissue by: Prevention of enzymatic degradation, Termination of cellular
metabolism, Killing of pathogenic microorganism & Hardening of tissue
Embedding
- Tissue preparation that hardens tissue (in parafin) to be
sectioned and mounted
Staining
- Turning colorless tissue into differential color visual images to be better examined and
studied
What are the types of staining methods? - Correct Answers -Acidic and basic dyes
Periodic acid-Schiff (PAS) reaction (for staining of carbohydrate or carbohydrate-rich
molecules)
Feulgen reaction (for staining of DNA)
Immunocytochemistry (direct & indirect)
Hybridization - fluoresence in situ hybridization (FISH), polymerase chain reaction
(PCR) & reverse transcriptase-PCR (RT-PCR)
Autoradiography
What are the 2 types of acidic and basic dyes? - Correct Answers -Hematoxylin and
eosin (H&E)
Basic dyes (*hematoxylin)
Acidic dyes (eosin)
What are the most commonly used dyes in the staining method (and in all of histology)?
- Correct Answers -Hematoxylin and eosin (H&E)
What are the features of acidic and basic dyes in staining methods? - Correct Answers -
Basic dyes (*hematoxylin) react with anionic components of cells and tissues
,- Dark blue or violet stain that is positive
- Phosphate groups of nucleic acids, sulfate groups of glycosaminoglycans, and
carboxyl groups of proteins
Acidic dyes (eosin) react with cationic groups in cells and tissues
- Red or pink stain that is negative
- Amino groups of proteins
What are the types of visualizing prepared specimens? - Correct Answers -Bright-field
microscopy (most common)
Electron microscope
Light microscopy
Transmission electron microscopy (TEM)
Scanning electron microscopy (SEM)
Atomic forces microscope (AFM)
What is the total body water in humans? - Correct Answers -0.6 x Body wt
What percent of the TBW is found in intracellular fluid? Extracellular fluid? - Correct
Answers -Intracellular fluid = 66% of TBW
Extracellular = 33% of TBW
What percent of the extracellular fluid is found in the plasma? interstitial fluid? - Correct
Answers -20% of the TBW in the extracellular fluid is found in the plasma
80% of the TBW in the extracellular fluid is found in the interstitial fluid
What is the main difference between prokaryotic and eukaryotic cells? - Correct
Answers -Prokaryotic cells lack a membrane bound nucleus (the genetic material is
located within the nucleiod)
What are the key features of a eukaryotic cell? - Correct Answers -Contains a nucleus
Has a cytoskeleton, allowing the cytoplasm to move in an orderly fashion as during
mitosis or cell movement
Contains membrane-bound and non membranous organelles ("little organs")
What is the plasma (cell) membrane composed of? What is the described as? - Correct
Answers -Dynamic structure composed of amphipathic (can interact with polar and non
polar entities) phospholipid bilayer, cholesterol, integral proteins, and peripheral proteins
*described as a fluid mosaic model
What are the 2 functions of the plasma (cell) membrane? - Correct Answers -Protective
barrier
Regulation of transport into and out of cell
What are the features of phospholipids in the plasma membrane? - Correct Answers -
Amphipathic molecule with polar
phosphate head and two non-polar fatty acid tails
, - meaning the head is able to interact with water or a charged environment and the tails
do not like to interact with water (showing why the tails face inwards and heads point
out)
What are the features of the cholesterol in the plasma membrane? - Correct Answers -
Steroid molecule that provides greater strength and rigidity to the phospholipid bilayer
- ALSO adds flexibility without the membrane being disrupted
What are the 2 types of proteins in the plasma membrane? - Correct Answers -
Peripheral proteins - associated with plasma membrane
Integral proteins - embedded within the plasma membrane or pass through membrane
completely (transmembrane)
What are the 5 functions of the proteins in the plasma membrane? - Correct Answers -
Channels / pumps / carriers (needed to shuttle substances in and out of the cell that
cant move through otherwise)
Receptors
Linker / anchor proteins
Enzymes (catalyst)
Structural proteins
What are the features of the glycoproteins in the plasma membrane? - Correct Answers
-Oligosaccharides (branched carbohydrate chain) attached to integral proteins on the
extracellular surface
What are the features of glycolipids in the plasma membrane? - Correct Answers -
Oligosaccharides attached to phosphate head of the phospholipid structure
Both glycoproteins and glycolipids function in cell-to-cell ______________, cell- to-cell
___________, and _____________ for intercellular interactions - Correct Answers -
identification
signaling
attachments
What are the features of the nucleus? - Correct Answers -Largest membrane-bound
organelle within the cell
Contains genetic materials
Protected by a nuclear envelope
What genetic material is found in the nucleus? - Correct Answers -DNA
(deoxyribonucleic acid) forming a double helix
DNA strands are wrapped around histones (proteins)
Tightly coiled to form chromatin
Heterochromatin - highly condensed chromatin (dense staining)
Euchromatin - loosely packed chromatin containing sequences of DNA that code for a
gene (light staining)
ANSWERS
Histology is the study of _______ and ______. - Correct Answers -Cells and tissues
What are the 4 primary tissues? - Correct Answers -Epithelial (squamous, cuboidal,
columnar)
Connective (connective tissue proper, cartilage, bone, blood)
Muscle (skeletal, cardiac, smooth)
Nervous (neurons and neuroglias)
What are 3 processes of preparing cells for study? - Correct Answers -Fixation
- Formalin (37% aqueous solution of formaldehyde)
- Preservation of tissue by: Prevention of enzymatic degradation, Termination of cellular
metabolism, Killing of pathogenic microorganism & Hardening of tissue
Embedding
- Tissue preparation that hardens tissue (in parafin) to be
sectioned and mounted
Staining
- Turning colorless tissue into differential color visual images to be better examined and
studied
What are the types of staining methods? - Correct Answers -Acidic and basic dyes
Periodic acid-Schiff (PAS) reaction (for staining of carbohydrate or carbohydrate-rich
molecules)
Feulgen reaction (for staining of DNA)
Immunocytochemistry (direct & indirect)
Hybridization - fluoresence in situ hybridization (FISH), polymerase chain reaction
(PCR) & reverse transcriptase-PCR (RT-PCR)
Autoradiography
What are the 2 types of acidic and basic dyes? - Correct Answers -Hematoxylin and
eosin (H&E)
Basic dyes (*hematoxylin)
Acidic dyes (eosin)
What are the most commonly used dyes in the staining method (and in all of histology)?
- Correct Answers -Hematoxylin and eosin (H&E)
What are the features of acidic and basic dyes in staining methods? - Correct Answers -
Basic dyes (*hematoxylin) react with anionic components of cells and tissues
,- Dark blue or violet stain that is positive
- Phosphate groups of nucleic acids, sulfate groups of glycosaminoglycans, and
carboxyl groups of proteins
Acidic dyes (eosin) react with cationic groups in cells and tissues
- Red or pink stain that is negative
- Amino groups of proteins
What are the types of visualizing prepared specimens? - Correct Answers -Bright-field
microscopy (most common)
Electron microscope
Light microscopy
Transmission electron microscopy (TEM)
Scanning electron microscopy (SEM)
Atomic forces microscope (AFM)
What is the total body water in humans? - Correct Answers -0.6 x Body wt
What percent of the TBW is found in intracellular fluid? Extracellular fluid? - Correct
Answers -Intracellular fluid = 66% of TBW
Extracellular = 33% of TBW
What percent of the extracellular fluid is found in the plasma? interstitial fluid? - Correct
Answers -20% of the TBW in the extracellular fluid is found in the plasma
80% of the TBW in the extracellular fluid is found in the interstitial fluid
What is the main difference between prokaryotic and eukaryotic cells? - Correct
Answers -Prokaryotic cells lack a membrane bound nucleus (the genetic material is
located within the nucleiod)
What are the key features of a eukaryotic cell? - Correct Answers -Contains a nucleus
Has a cytoskeleton, allowing the cytoplasm to move in an orderly fashion as during
mitosis or cell movement
Contains membrane-bound and non membranous organelles ("little organs")
What is the plasma (cell) membrane composed of? What is the described as? - Correct
Answers -Dynamic structure composed of amphipathic (can interact with polar and non
polar entities) phospholipid bilayer, cholesterol, integral proteins, and peripheral proteins
*described as a fluid mosaic model
What are the 2 functions of the plasma (cell) membrane? - Correct Answers -Protective
barrier
Regulation of transport into and out of cell
What are the features of phospholipids in the plasma membrane? - Correct Answers -
Amphipathic molecule with polar
phosphate head and two non-polar fatty acid tails
, - meaning the head is able to interact with water or a charged environment and the tails
do not like to interact with water (showing why the tails face inwards and heads point
out)
What are the features of the cholesterol in the plasma membrane? - Correct Answers -
Steroid molecule that provides greater strength and rigidity to the phospholipid bilayer
- ALSO adds flexibility without the membrane being disrupted
What are the 2 types of proteins in the plasma membrane? - Correct Answers -
Peripheral proteins - associated with plasma membrane
Integral proteins - embedded within the plasma membrane or pass through membrane
completely (transmembrane)
What are the 5 functions of the proteins in the plasma membrane? - Correct Answers -
Channels / pumps / carriers (needed to shuttle substances in and out of the cell that
cant move through otherwise)
Receptors
Linker / anchor proteins
Enzymes (catalyst)
Structural proteins
What are the features of the glycoproteins in the plasma membrane? - Correct Answers
-Oligosaccharides (branched carbohydrate chain) attached to integral proteins on the
extracellular surface
What are the features of glycolipids in the plasma membrane? - Correct Answers -
Oligosaccharides attached to phosphate head of the phospholipid structure
Both glycoproteins and glycolipids function in cell-to-cell ______________, cell- to-cell
___________, and _____________ for intercellular interactions - Correct Answers -
identification
signaling
attachments
What are the features of the nucleus? - Correct Answers -Largest membrane-bound
organelle within the cell
Contains genetic materials
Protected by a nuclear envelope
What genetic material is found in the nucleus? - Correct Answers -DNA
(deoxyribonucleic acid) forming a double helix
DNA strands are wrapped around histones (proteins)
Tightly coiled to form chromatin
Heterochromatin - highly condensed chromatin (dense staining)
Euchromatin - loosely packed chromatin containing sequences of DNA that code for a
gene (light staining)
