Producing Tissue Cultures of Explants | AQA A Level Biology Revision Notes 2017

Apparatus & Techniques: Producing Tissue Cultures from Cauliflower Explants

Creating clones of cauliflowers is used to demonstrate totipotency through the production of tissue culture
Cauliflower is used because it is comprised mostly of actively dividing cells and can withstand being handled
Many plant cells are totipotent, unlike animal cells, and therefore an entire plant can be reproduced from any of these cells
A small piece of the plant is cut, this is called an explant, which is then grown into a new clone of the original plant
This technique is used by scientists to reproduce endangered species of plant

Wipe all surfaces with disinfectant and soak all apparatus in sterilant
- It is important to ensure a sterile environment so that no fungi contaminate the experiment, which would result in seeing a fungal growth rather than an explant growth
Break of a small floret of cauliflower from the plant then using a scalpel, cut a thin section of the floret (about 1cm long)
- This thin section is the explant
Sterilise the explant by soaking it in sterilising solution for 15 minutes, swirling the explant around within the solution every couple of minutes
- This ensures that the explant is sterile and therefore only cauliflower cells are present
Take out the explant using sterilised forceps and add it to a container of agar growth medium
- The growth medium contains all the nutrients that the plant needs for growth and also contains a sterilant to ensure no contamination occurs throughout the experiment
Leave the container holding the agar growth medium and the explant on a sunny windowsill for 3 weeks

The result of this experiment is to grow a cauliflower clone from an explant
This shows that the cells in the explant have the capability to produce all the different cell types that make up a full cauliflower plant, hence they are totipotent