plant stem cells and plant tissue culture- lqc 4a

Question 1

plant cells remain

Answer 1

totipotent throughout life, so a complete plant can be grown from a fragment (explant) of a leaf, stem or root, or from a single cell, by plant tissue culture. An explant of plant tissue is placed on sterile agar containing nutrients and growth regulators, using aseptic technique. The explants are placed under a light bank for around 4 weeks. Cells differentiate to form a whole plant, which is a clone of the original plant (genetically identical to it).

Question 2

plant tissue culture can be used to

Answer 2

• Improve plant and food crop species e.g. create disease resistant plants
• Produce increased quantities of plant chemicals used in drugs e.g. taxol from Yew trees
• Produce commercial plants that are difficult to grow from seed e.g. orchids
• Conserve endangered plant species