Category Science

                      The impressions of fossilized leaves are commonly found in coal. The most common fossils are of ferns, mosses and horsetails, all of which still grow on the Earth today. Coal was formed in shallow bogs, where plants died and were gradually buried by more material, until pressure and time converted them into coal. The oldest coal was formed 350 million years ago, and the process still continues in swamps and bogs. Peat is the earliest stage in the formation of coal. It has not yet been subjected to the pressure that will eventually turn it into a hard material.

Picture credit: google

                    Algae are the most primitive form of plant life. Most algae are aquatic, and they range in size from microscopic single-celled organisms to seaweed that is several metres long. Algae photosynthesize, like other plants, and they are responsible for providing most of the world’s oxygen. Algae are very varied, but even the large forms, such as kelp and other seaweeds, lack the true leaves, stems and roots found in other plants. Not all algae use the green chlorophyll found in other plants in order to photosynthesize; some use red or brown pigments for this purpose.

Picture credit: google

                      Scientists believe that the first primitive plants appeared about 1,000 million years ago. It is difficult to be certain about the date, because simple organisms do not usually leave fossils. However, these primitive plants are thought to have laid down fossil deposits, rather like coral reefs, in shallow seas.

Picture credit: google

                   Plants growing in bogs and peaty areas often need to supplement their food supply by catching insects. Bog water contains very little nitrogen, but some bog plants can obtain this substance by catching and digesting insects. They are known as insectivorous plants. Some have vase-shaped structures, into which insects are lured by bright colours and scents, like flower nectar. They fall into a slippery funnel and drop into a pool of liquid containing digestive juices. Other insectivorous plants are covered with sticky tentacles that trap flies. The most remarkable is the Venus’s flytrap plant. It has two clawed plates that slam together when a fly walks over them and touches a trigger hair.

                      Other insect-eating plants are aquatic, catching tiny crustaceans in bladder-shaped-underwater traps. Some of the largest insectivorous plants live in the tropical rainforests of Southeast Asia. They produce hanging, vase-shaped traps as big as a fist.

Picture credit: google

                   Plants store food and water over the winter, or in dry conditions. Underground storage organs develop from roots, stems or leaf bases, and we use many of these plant organs as foods, for example potatoes and carrots. Bulbs and corms are common storage organs, which are familiar in many garden plants. Above the ground, desert plants have swollen stems or leaves in which they store water.

Picture credit: google

                  Many plants are able to move their leaves slowly to keep them facing the sunlight. In same plants, this movement is very fast. The sensitive plant suddenly collapses all its leaves when touched, and looks as though it is dead. This is to help protect it from grazing animals. Other forms of movement happen when a plant distributes its seeds. Some plants can ‘fire’ their seeds for a considerable distance, making sure that the new plants do not grow too close.