Plants Definition

Plants are eukaryotes, or multicellular organisms. Plants, like mammals, have a membrane-bound nucleus inside their cells. The nucleus is an organelle that houses genes on chromosomes. Golgi apparatus, endoplasmic reticulum, lysosomes, peroxisomes, and plastids are further organelles suspended in the cytoplasm of a plant cell.

Plastids are found in plants. Plastids inside a eukaryotic cell indicate that it is more likely a plant than an animal. Plastids are available in a wide range of forms and sizes.

Chloroplasts are photosynthesis-related plastids that contain chlorophyll (green pigments). Apart from green, chromoplasts include pigments and are involved in pigment production and storage. Light energy is absorbed by chlorophyll systems at certain wavelengths in the electromagnetic spectrum.

Pigments also contribute to the colour of plant structures (e.g. green leaves, red flowers, yellow fruits). Non-pigmented plastids, such as amyloplasts, elaioplasts, and proteinoplasts, are known as leucoplasts. Their primary use is to store food. Sugar, such as starch, is used by plants to store food.

Inside the cell of plants, there is a huge vacuole. This cytoplasmic structure is important in turgor pressure control.

Apart from the plasma membrane, plants have stiff cell walls. A plant cell’s cell wall provides additional structural support.

Plants do not have a skeletal structure like animals, but their cell walls are largely made of cellulose material, which helps to provide structural support.

Plants have a unique cell division system in which daughter cells are separated by a cell plate (phragmoplast). Plants do not have the same mobility as mammals. They are unable to go from one area to another at their leisure. As a result, they must contend with extreme weather, such as heat. Their cell walls, which keep their bodies from drying up, are one of the ways they can endure heat.

Plants, meanwhile, continue to move, albeit in a different way. The folding of the leaflets of the plant Mimosa pudica when touched, for example, and the shutting of the leaf of the Venus flytrap while trapping prey are both examples of nastic movement.

Some plants, such as the silver birch Betula pendula, would even droop their branches and leaves at night, as if they were “sleeping.” Tropism is another type of plant movement.

Tropism, on the other hand, is more of a response to a stimulus than a movement. Plants, for example, prefer to grow towards the light source (phototropism).

Plasmodesmata are plasmodesmata found on plants. Plants contain plasmodesmata, which behave as if they were cell connections between plant cells, but animals have cell junctions that keep cells in an animal tissue.

These cytoplasmic bridges between neighbouring cells are formed by the cell wall. These “bridges” assist maintain the tonicity of plant cells by facilitating cell contact and allowing fluid circulation.

Plants are multicellular, with numerous cells organised into tissues and organs that work together to accomplish a specific purpose.

Anchorage, support, and photosynthesis are all specific functions of plant organs (e.g. roots, stems, leaves, etc.) Plants can grow indefinitely thanks to their meristematic tissues. Indeterminate, actively dividing cells make up the tissue, which gives birth to differentiated tissues including epidermis, trichomes, phellem, and vascular tissues.

Plants do not have sensory organs, yet they may detect their surroundings in a variety of ways. Despite their absence of eyes, ears, and noses, plants can “see,” “hear,” and “smell.” They appear to “feel” and respond in ways that animals do not.

Plants may not have the same nervous system as mammals, but they appear to have their own system based on how they respond to their environment.

Despite not having eyes, Arabidopsis has photoreceptors (at least 11 kinds) that let the plant perceive light. Herbivory, for instance, might cause the release of specific compounds on the damaged plant component.

Herbivores are deterred by the production of defensive compounds by plants. Tomatoes have been seen emitting volatile signals to warn adjacent plants of an imminent herbivore assault.

Plants reproduce in two ways: asexually and sexually. Plants reproduce asexually by budding, fragmentation, fission, spore development, vegetative propagation, apomixis, and other methods.

Male and female gametes merge during fertilisation, resulting in sexual reproduction. In general, the plant life cycle includes generational alternation, or the sporophyte and gametophyte stages alternating.

Plants are able to “breathe.” Carbon dioxide from the atmosphere enters the plant cell through stomata. Carbon dioxide is transformed to oxygen during photosynthesis, which the plant releases as a metabolic by-product into the environment through the stomata.

Plants may lack other biological systems, but they do generate compounds that aid in plant defence and immunological activities, as well as plant hormones that operate as signalling molecules.