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ContentsDefinitionHistoryApplicationsBenefitsProcedureContaminationDisadvantagesConclusion

DefinitionTissue culture is a special type of asexual

propagation where a very small piece of tissue (shoot apex, leaf section, or even an individual cell) is excised (cut-out) and placed in sterile (aseptic) culture in a test tube, petri dish or tissue culture container containing a special culture medium

Tissue culture is a way to maintain the viability of an animal or plant tissue outside the donor's body.

HistoryIn 1885 Wilhelm Roux removed a section of

the medullary plate of an embryonic chicken and maintained it in a warm saline solution for several days, establishing the basic principle of tissue culture

In 1907 Ross Harrison at the Rockefeller Institute cultured frog embryo nerve fibers and successfully demonstrated growth of the nerve fibers outside a living body or in culture mediums

Further investigations led to comprehensive protocols that allow for sterilized or contamination-free culture methods.

Applications-Medicine and Research

• There are various applications of tissue culture in a wide array of scientific industries.

• Cancer cells are analyzed in vitro to produce appropriate medicines that will eliminate the abnormal cells.

• Skin grafting, wherein severely burned tissues are replaced with new ones using cultured cells.

Applications-Plant Fiber Culture

One of the most common types of tissue culturing is conducted in botanical and agricultural research.

Plant tissue is much easier to grow in a nutrient rich suspension than human or animal tissue, and with the right nutrients, different tissue samples can often be encouraged to develop as they would on a normal plant specimen.

Applications- Genetic Modification

Plant tissues are also cultured when experimented with genetic modification.

Most gene modification on plants is conducted to alter a specific part of the plant and the way it grows. By isolating those tissues and growing them in a lab, scientists can quickly test their gene modification and spot any problems

Points to considerfor Tissue CultureThe culture medium contains a gel (agar) with

the proper mixture of nutrients, sugars, vitamins and hormones, which causes the plant part to grow at very rapid rates to produce new plantlets.

A very specialized laboratory is required for tissue culture. All the procedures are done in a laboratory and special ventilated cabinet that is as sterile as an operating room.

MethodsBiopsy Swabs

These methods may involve suction, forceps or needle extractions.

Provide a lot of cells for testing or observation.

This is a painful and an invasive method of tissue collection.

The process includes using a wooden dowel or cotton swab and wiping it along the section of the body being tested

This removes the cells mechanically and deposits them onto the collection surface

This is a non-painful method of collection and limits invasive techniques.

Plant tissue culture

These are the different stages of growth

BenefitsExact DuplicationTissues harvested from a plant create an

exact duplication, with the same genetic material and physical characteristics.

Timely DuplicationIf a rare or slow-growing plant has not

flowered or produced seed, tissue culture facilitates new plant development at any time of year.

BenefitsDisease AvoidanceIf a plant is diseased, tissue from small areas of the

plant not inflicted by the disease can be taken to produce healthy, new plants. Moreover, the isolated sterile environment of the tissue culture itself can prevent spread of diseases and insect pests.

EconomicsIndoor laboratories can produce huge and repeated

numbers of plants year round in small spaces, a huge advantage over traditional propagation techniques like sowing and rooting cuttings

Tissue culture

A disease free plant

Procedure-Cell Types and LinesPrimary cells come directly from a living organism

and they can originate from any organ. These cells are difficult to culture because they have limited ability to divide, making their life spans short.

Finite cell lines also come directly from animal tissues and are difficult to propagate. These cells can be cultured over several generations

Continuous cell lines come from an action called transformation whereby their genetics have spontaneously changed in culture. These cells are easy to propagate because they have an almost indefinite lifespan

Procedure- Culturing cellsThe method of cell culture will be different for

each cell typeMost cells are kept frozenFrozen cells must be thawed in a 37o C warm

water bath quickly in order to prevent unnecessary cell death. In addition, the growth media that is used in the plates should also be warmed prior to use. After thawing, transfer the cells to a culture dish with the prescribed amount of nutrient media and incubate for 24 hours. This time period allows the cells to stick to the bottom of the dish so that the media can be removed the next day and replaced with fresh media.

Procedure- Observation and MaintenanceMonitor your cells daily by looking at them under

the microscope. Look for signs of failure, such as many floaters.

Use the suction tip in the tissue culture hood to evacuate the media and dead cells and then refresh with new media.

Healthy cells should replicate. When the bottom of the plate is almost fully covered with cells, it is time to split them.

This is done by washing the cells with a buffer solution and then detaching the cells from the bottom of the plate using media and a pipette or scraping

Contamination- Chemical ContaminationChemical contamination is the presence of any

non-living substance in the cell culture that causes adverse effects to the cells

This include impure media, serum or even water which may contain undesirable endotoxins

Exposure to too much fluorescent lighting can alter the chemical composition of the media negatively.

Chemical contaminants could also come from unclean storage vessels.

Contamination- Cross Culture ContaminationCross culture contamination occurs when a

different cell type is inadvertently introduced into the cells that are being cultured.

Cross culture contamination voids the experiment because the effect of the contaminating cells is unknown.

Contamination- Bacteria, Fungi or YeastThese microorganisms are the most common

cell culture contaminatorsVisual indicators of contamination include

media color changePresence of non-cellular materialCell vacuolizationMycoplasma (parasite)are very small

bacteria-like organisms that are troublesome contaminators

It can’t be detected by these indicators

DisadvantagesTissue culture has both positive and negative aspects.

Cost FactorPlant tissue culture experiments involve high cost

because of the expensive machinery required.

ComplexityPlant tissue culture is a complex scientific analysis.

The procedure is multifaceted depending on the type of plant being incubated.

the plants all have the same genetic material, genetic diversity is reduced

ConclusionTissue culturing is an important advancement

in biological research that allowed investigators to analyze the growth, development and function of cells.

To carry out tissue culturing effectively, several factors such as light, temperature, type of culture medium and pH must be strictly maintained

It has both advantages and disadvantages. So it is in our hands to use it carefully