1.2 Introduction to Tissue Architecture Flashcards
How are histological samples prepared?
1) Fixation/Processing of sample
2) sectioned to view on slide
3) stained to make the tissue visible
What does the shape of individual cells and how they are arranged in tissues tell us?
How they do their jobs (and whether they are doing their jobs.)
Hematoxylin stain does what?
Stains nuclei (RNA/DNA) blue/purple
Eosin Stain does what?
Stains the cytoplasm pink
2 says to cut through a long organ?
Transverse = across the object, through its longest axis
Longitudinal = Along the longest axis
Strategy to identify what you are looking at?
Organisms are made of organs
Organs are made of tissues
Tissues are made of cells and matrix
The best approach is to work down this list from the top
Where are epithelia tissues found?
They are found at the edges of tissues and so have liquid or air on one side
What is this organ?
gland - exist to secrete substances into the circulation. As they function as an interface they contain lots of epithelia.
Cuboidal epithelium
What organ is this?
blood vessels
squamous epithelium
What organ is this?
part of the gut
columnar
Squamous :
- flattened
- passive barrier
- blood vessels
cuboidal:- Square shaped
- Round nucleus
- Glands, secret
columnar:- Elongated shape
- Oval nucleus
- Gut linning
- Active barrier
“simple” means?
that there is only one layer of cells
relatively passive –> relatively active order
simple squamous –> simple cuboidal –> simple columnar
stratified means?
multiple layers of cells
outer layer can be removed / replaced
stratified cubodial
multiple layers of cells provide?
protection to the tissue
where do connective tissues lie?
between the epithelia
What do connective tissues contain?
They contain proteins to hold everything together, cells which do particular jobs for the tissue and blood vessels etc which carry things in and out of the tissue
Transitional Epithelium:
Stratified epithelium with cells changing depending on stretch
ex: bladder
Pseudostratified:
Single layer of epithelial cells, arrangement of nuclei makes it look like multiple layers
extracellular matrix
Network of proteins for support
fibroblasts - Produce ECM, typically are long and thin, with long nuclei
Dense irregular
Dense connective tissue:
- Provides firm attachment / stability
- collagen fibers
- contains fewer cells
Dense regular
Dense regular
fat cells
loose connective tissue
- Provides cushion / support
- contains more ground substance
- has relatively few fibers
- ex: between muscles, around blood vessels and joints
Epithelia form?
boundaries and barriers
basement membranes
Glands:
exist to secrete substances into the circulation
The gut functions to?
absorb nutrients into the body.
3 main types of muscle:
- skeletal/striated - voluntary
- cardiac - involuntary
- smooth
skeletal muscle
2 Forms of nerve tissue:
- part of the CNS
- nerve bundle in muscle tissue
Part of CNS
never bundle in muscle tissue