Explants are small pieces of plant parts or tissues that are aseptically cut and used to initiate a culture in a nutrient medium. Explants can be taken from different parts of a plant such as shoots, leaves, stems, flowers, roots, and from many types of mature cells provided they are able to de-differentiate into totipotent cells. Continue reading What are Explants?
Cellular Totipotency is the ability of a single cell to produce all cell types and to organize them into an entire organism when cultured in a suitable culture medium at an appropriate temperature and aeration conditions. Spores and Zygote are examples of totipotent cells. Continue reading What is meant by Cellular Totipotency?
Swim Bladder, also called air bladder, is an expandable gas-filled sac that helps many bony fishes to control their buoyancy in order to stay at their current water depth without having to waste energy in swimming. A swim bladder is similar to a lung in structure and function in some primitive fishes, but it is not a lung because most cases its primary role is not respiration. Continue reading What are Swim Bladders?
The continued secondary growth of vascular cylinder in many older roots and stems exerts a pressure which results in the stretching and rupturing of the epidermis, cortex and other tissues outside the secondary phloem. To avoid such breaking of external tissues, the plant organs develop a secondary protective covering by replacing epidermis and other external tissues. This protective secondary covering (tissues) of certain plants, especially woody plants, is called Periderm. Continue reading What is Periderm in Plants?