Pollen magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower. Pollen itself is not the male gamete. Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive)
Decay theory that older memories (in long-term memory) are often more resistant to shocks or physical attacks on the brain. It is also thought that the passage of time alone cannot cause forgetting, and that decay theory must also take into account some processes that occur as more time passes. The term "decay theory" was first coined by Edward Thorndike in his book "The Psychology of Learning" in 1914. This simply states that if a person does not access and use the memory representation they have formed the memory trace will fade or decay over time. This theory was based on the