Principles of histology Flashcards
What is histology?
It is the microscopic study of normal tissues and organs
What is cytology?
It is the examination of a single cell type
The cytoskeleton function
Cytoskeleton:
- supports the cell
- holds organelles in place
-helps in movement
- consists of filamentous proteins that reversibly assemble to allow remodelling
Cytoskeleton filaments consist of…
- Microfilaments- actin filaments
2.intermediate filaments - in skin cells they resist strain - Microtubules - stiffer than actin filaments involved in segregation of chromosomes, movements of flagella/cillia
functions of the endoplasmic reticulums
RER- contain ribosomes to synthesise proteins
SER- produces lipids and stores ca2+ in muscle cells
Function of the Golgi apparatus
Concentrate and modify proteins and lipids from the ER and package the into either vesicles.
Functions of vesicles
Secretory vesicles- secrete substances e.g insulin in islets of langerhans
Peroxisomes- contain enzymes that break down hydrogen peroxide, fatty acids and amino acids, found in the cells active in detoxification e.g liver cells
Function of mitochondria
Have smooth outer and folded inner membranes enclosing the matrix
In animals, mitochondrial DNA inheritance is almost exclusively maternal- mutations in mitochondrial DNA are transmitted from mother to foetus
E.g - diabetes mellitus
- epilepsy
- proximal weakness
- cardiomyopathy
Goblet cells are secretory cells that secrete…
Mucus
Name the 4 primary tissue types
Epithelium
Connective tissue
Muscle tissue
Nervous tissue
How is epithelium classified
Layers:
- simple (one)
- stratified (more than one)
- pseudostratified (one layer but looks like more)
Cell shape:
- squamous (flat)
- cuboidal
- columnar (tall)
- transitional (changing)
What do these suffixes mean
1.-blast
2.-cyte
3.-clast
1.build
2. Mature
3. Destroy
What type of epithelium?
Simple cuboidal
What type of epithelium?
Simple columnar
What type of epithelium?
Simple squamous
What type of epithelium?
Stratified squamous
What type of epithelium?
Pseudostratified columnar
What type of epithelium?
Transitional
Extracellular matrix has 3 components
- Fluid
- Ground substance
- Protein fibres (3)
- collagen
- reticular
- elastic
Exocrine glands secrete into…
A ductal system
endocrine glands secrete into…
The bloodstream
What is haemotoxylin
Basic (alkaline) dye that dyes basophilic (acidic) structures blue/purple
E.g DNA in nucleus
What is eosin
Acidic dye that dyes acidophilic (basic) structures pink.
E.g proteins within the cytoplasm
3 main techniques for preparing samples for histological analysis
- Paraffin technique
- frozen sections
- semithin sections
Loose connective tissue consists of…
Loose arrangement of fibres (collagen, elastin) with other cells such as fibroblasts, adipocytes, plasma cells etc.
E.g lymph gland
Dense irregular connective tissue consists of…
Densely packed network of collagen and elastic fibres, fibroblasts are also present.
E.g found in dermis
What are fibroblasts
Primary cell of connective tissue
Dense regular connective tissue consists of…
Densely packed collagen fibres running parallel to each other, fibroblasts and capillaries are still present.
E.g ligaments
