Cell Biology Techniques Flashcards
(17 cards)
Define histology.
Study of tissues and their microscopic structure, providing a detailed view of cellular organisation.
Define histopathology.
Study of diseased tissues, offering critical tool for diagnosing conditions such as cancer and infections.
Describe how a histological analysis happens.
1) tissue is collected through biopsy or surgical specimens.
2) tissue is preserved using a fixative, like formalin, to prevent degration and maintain cellular components.
3) tissue is embedded in paraffin wax, sliced into thin sections (3-20microM) and mounted onto microscopic slide.
4) sections are stained with H&E
What does H&E stand for?
Hematoxylin and eosin.
What stain does hematoxylin leave on slide?
Stains acidic structures, like nuclei, a dark blue/purple.
What stain does eosin leave on slide?
Stains basic components, like cytoplasm, pink.
How is histopathology needed in cancer diagnosis?
Histopathology helps distinguish between benign and malignant tumours by assessing cellular morphology and organisation.
How is histopathology needed in infectious disease?
To detect pathogens like bacteria/fungi within tissues.
What is meant by ‘cell culture?’
Growing cells outside natural environment under lab control.
Indispensable for studying cellular behaviour, testing drugs, and producing biological products.
Name and describe 2 types of cell cultures.
1) primary cell culture- from tissues, cells closely mimic their in vivo counterpart but have a limited lifespan.
2) immortalised cell lines- cells are modified to proliferate. Eg. Hela cells from cervical cancer and HEK-293 cells from human embryonic kidney cells.
Steps in cell culture.
1) cells are isolated from tissue sample and placed in growth medium containing nutrients (including like glucose, AA’s, vitamins), fetal bovine serum (provides growth factors) and antibiotics (like penicillin and streptomycin).
2) cells maintained in incubators with temp of 37C. CO2 levels are controlled.
3) adherent cells, like epithelial cells, attach to surface of culture flask while non-adherent cells, like blood cells, grow in suspension.
Give 4 applications of cell culture.
1) cancer research- testing side effects of chemotherapeutic agents on tumour cell lining
2) drug development- screening potential drugs for efficiency and toxicity
3) regenerative medicine- culturing stem cells for therapeutic applications
4) biopharmaceutical production- manufacturing proteins like insulin and monoclonal antibodies
Features of light microscope.
- uses light
- bight field microscopy
- provides clear image of stained tissues
- advanced techniques like phase contrast and fluorescent microscopy which enhances contrast and allow study of like cells/specific molecules
Features of electron microscope.
- high resolution
- uses electron beams
- transmittion electron microscopy (TEM) shows the internal structures in detail
- scanning electron microscopy (SEM) shows 3D images of surface features.
Considerations with cell culture and microscopy.
- contamination. Cell cultures are prone to bacterial, fungal or cross contamination. Strict aseptic techniques are essential
- artefact formation. During tissue preparation, artifices like folding/tearing can distort histological results
- relevance. While cell culture systems provide valuable insights, they may not fully replicate in vivo conditions
What is PCR?
a method for amplifying DNA sequences.
What is western blotting?
A technique for detecting specific proteins.
