Histological Techniques + More Flashcards
What is the purpose of staining in light microscopy?
Enhances contrast for structure differentiation
What type of dyes stain acidic cell structures well?
Basic dyes
What type of dyes stain alkaline structures well?
Acidic dyes
What does Hematoxylin stain?
Basophilic (acidic) structures blue
What does Eosin stain?
Eosinophilic (alkaline) structures red
What color does PAS stain carbohydrates?
Pink
What appearance does muscle have with Van Giesen’s stain?
Yellow
What appearance does collagen have with Van Giesen’s stain?
Red
What color does muscle appear with Trichrome stain?
Red
What color does collagen appear with Trichrome stain?
Blue
What color do elastic fibers appear with Verhoeff stain?
Black
What color do reticular fibers appear with silver stain?
Black
What is the composition of the cell membrane?
Lipid molecules (phospholipids), cholesterol, and proteins
What is the function of the cell membrane?
Selectively permeable barrier, enabling transport and communication
What are the types of membrane proteins?
- Structural
- Transport
- Enzymatic
- Receptor
- Adhesion
What is the glycocalyx?
Carbohydrate layer providing protection, lubrication, and cell recognition
What are the types of membrane transport?
- Passive (diffusion, facilitated diffusion)
- Active (carrier proteins, ion pumps)
- Endocytosis (phagocytosis, pinocytosis)
- Exocytosis
What are endosomes?
Membrane-bound vesicles for intracellular sorting
What is the role of early endosomes?
Sort endocytosed material near plasma membrane
What do late endosomes do?
Degrade material and merge with lysosomes near Golgi
What do lysosomes contain?
Hydrolytic enzymes
What do lysosomes digest?
- Microorganisms
- Cell debris
- Old organelles
What leads to lysosomal storage diseases?
Failure to degrade substances
What do peroxisomes contain?
Oxidative enzymes
What is the function of peroxisomes?
Convert hydrogen peroxide into water to prevent cellular damage
Where are peroxisomes abundant?
Liver and kidney cells
What is the primary function of mitochondria?
Generate ATP via oxidative phosphorylation
What is unique about the structure of mitochondria?
Double-membrane structure with inner folds (cristae)
What does the mitochondria contain that is unique?
Own DNA, capable of self-replication
What is the function of chloroplasts?
Site of photosynthesis
What is the largest cellular compartment?
Cytosol
What is the consistency of cytosol?
Gel-like
What is the site of metabolic reactions and protein synthesis?
Cytosol
What is glycogen?
Storage form of glucose, abundant in liver and muscle cells
What are lipid droplets?
Energy reserves found in adipocytes
What is melanin responsible for?
Skin/hair color
What is hemosiderin?
Iron-storage pigment, accumulates in conditions like hemosiderosis
What is lipofuscin known as?
Aging pigment
What is the function of the cytoskeleton?
Provides structural support
What are the functions of the cytoskeleton?
- Aids in cell movement
- Intracellular transport
- Division
What are microfilaments composed of?
Actin filaments
What is the size of microfilaments?
Smallest (7 nm)
What are intermediate filaments responsible for?
Provide tensile strength and structural stability
What is the size of intermediate filaments?
Medium-sized (10 nm)
What are microtubules composed of?
α- and β-tubulin dimers
What is the size of microtubules?
Largest (25 nm)
What is the function of microtubules?
Serve as tracks for intracellular transport and mitotic spindle formation
