The plant kingdom is made up of a group of multicellular eukaryotes. These organisms all have cell walls and most of them contain chloroplasts. They can carry out photosynthesis independently and produce nutrients for their own growth. This group of organisms first evolved from green algae in the ocean. According to the order of evolution, they can be divided into mosses, ferns, gymnosperms and angiosperms.
Moss
Moss is the first plant to appear on earth. It evolved from algae found in the ocean. Moss plants have cuticle on their surface, which can protect their body well and prevent rapid and excessive water loss. However, because moss plants have not developed vascular bundles, the transport of water and nutrients is very slow, which largely explains the small size of their growing individuals.. Additionally, mosses need a moist environment to thrive, which is why this group of green dwarf plants are often found on damp floors, walls, or tree trunks. Common bryophytes include liverwort and earthmane.
Ferns
Scientists often call ferns lower vascular plants. This is mainly because ferns do not produce seeds, but rely on the production of spores to propagate. Ferns like to grow in dark, damp places. The stems of ferns are often buried underground and are called subterranean stems. The stems of some ferns are erect and tall, like the feather tree. Fern leaves are mostly pinnate and there are often piles of sporangia on the back. These sporangia are called sporangia piles. The spores of the sporangium are so small that they can only be seen under a microscope. Mature spores swell out of the sporangium and are carried away by the wind. Most of the coal we burn today was formed after many large ferns died off in the Carboniferous and were buried deep in the ground. They have evolved over a long period of time.
Gymnosperms reproduce by producing plant seeds, and gymnosperm seeds are exposed outdoors. The seeds produced by most gymnosperms are shaped like fruits. These fruit seeds are all composed of numerous scales and. is divided into male and female. When the male fruit ripens, the pollen grains produced under the scales are carried by the wind to the female fruit. There are exposed ovules inside each scale of the female fruit and the ovules contain eggs. After fertilization, the ovule develops into a naked seed without an envelope. Many gymnosperm seeds have invisible wings.es that allow them to be dispersed by the wind over great distances and then fall to the ground to take root. In real life, common plants like pine, fir, and cypress are gymnosperms.
Angiosperms
Angiosperms are plants that can flower and use the flowers as reproductive organs. Because angiosperms cannot fertilize stamens and pistils on their own, they transform their reproductive organs into floral structures to attract pollinators and help them fertilize. This is why angiosperms are also called flowering plants. Over the course of several evolutions, angiosperms managed to occupy the dominant position among continental plants. The seeds of angiosperms are enveloped in fruits and protected, and the fruits help the seeds disperse. people can Depending on the number of cotyledons contained in the seed, angiospermshave divided into monocots and dicotyledons. Most monocotyledonous plants have leaves with parallel veins and petals of three or multiples of three, such as lilies, rice, wheat, sugar cane, corn, bamboo, onions and garlic. Most dicotyledonous plants have leaves with reticulate veins and petals of four, five, or multiple. Common plants include rhododendron, banyan, chrysanthemum, celery and strawberry, water lotus and water lily. There are many types of angiosperms. Most of the trees, flowers, plants and vegetables that we see daily are angiosperms that can be used for human consumption, medicinal or ornamental purposes, and play an extremely important role in human life.
People can also divide plants into three categories: positive plants, negative plants, and shade-tolerant plantsaccording to their different light intensity needs. Plants can also be divided into four categories: long day plants, short day plants, neutral day plants, and medium day plants based on the length and response of the plants to sunlight during the flowering process.