Lecture 5A

Question 1

What are the techniques to examine cells

Answer 1

 Tissue culture

 Imaging cells

Question 2

What do you examine in cells

Answer 2

• Physiological properties
• Structures
• Organelle arrangement
• Cellular processes
• Environmental interactions

Question 3

What processes can be studied in CELLULAR PROCESSES

Answer 3

• Active and passive transport – movement of
molecules into and out of cells
• Adhesion – holding together cells and tissues
• Cellular reproduction and division
• Cell movement: e.g. Chemotaxis
• Metabolism: e.g. glycolysis, respiration, photosynthesis
• DNA repair, cell death and senescence
• Cell signalling – regulation of cell behaviour by signals from outside

Question 4

Definition of TISSUE CULTURE

Answer 4

“The maintenance and growth of the cells of multicellular organisms outside the
body ….. under precise conditions of temperature, humidity, nutrition, and
freedom from contamination”.

Question 5

What does tissue culture involve?

Answer 5

▫ Isolating cells from a specific tissue (primary cell culture)
▫ Maintaining growth in culture medium under conditions specific to the cell type

Question 6

Tissue culture requires

Answer 6

▫ Tissue culture to be carried out using aseptic technique
▫ Working in a designated tissue culture cabinet
▫ Special coated culture dishes

Question 7

TYPES OF CELLS

Answer 7

Cell line (immortal): cells that continue to grow following sub‐culture

• CHO – derived from Chinese Hamster Ovary
• VERO – derived from African Green Monkey
• HeLa – derived from Human cervix epitheloid carcinoma
• Can be stored in Liquid N2;

Question 8

GROWING CELLS IN CULTURE in 2 ways

Answer 8

Adherent culture and Suspension culture

Question 9

How to grow Adherent culture

Answer 9

• Appropriate for most cells including primary cells
• Dissociate cells enzymatically (e.g. trypsin)
• Growth is limited by surface area
• Culture dish must be coated*

Question 10

How to grow Suspension culture

Answer 10

• Appropriate for non‐adherent cells
• Does not require enzymatic dissociation
• Growth is limited by cell concentration
• Culture dish does not require treatment but requires agitation

Question 11

Requirement for TISSUE CULTURE OF MAMMALIAN

CELLS

Answer 11

• Tissue‐culture treated dish
• Culture medium containing specific nutrients
• Cells grown in a humidified CO2 incubator under regulated
conditions (i.e. 37 °C and 5 % CO2)
 Humidified environment prevents
evaporation
 CO2 maintains physiological pH (7.2‒7.4)
through the interaction with bicarbonate in
cell culture medium
 HCO3‐ + H+ H2CO3 CO2 + H2O

Question 12

What is HeLa cells

Answer 12

• Epithelial
• From human cervical cancer
• Adherent
Cancer research: effect of hormones on cancer cell proliferation
• To examine how viruses infect human cells (e.g. Parvo virus)
• To examine organelles, protein localisation, cell signalling…….through visualisation

Question 13

What cell organelles to stain

Answer 13

• DNA
• Proteins
• Lipids
• Antibodies

Question 14

Ways to detect staining

Answer 14

Fluorescence microscopy
• Microscopy techniques (e.g. luminescence and electron)
• Interactions with antibodies (e.g. Immunoprecipitation and immunofluorescence)
• Spectroscopy (e.g. fluorescence spectroscopy including fluorescence resonance energy transfer, FRET)