Railway Science (Biology – Plant Kingdom)

Bioremediation is a technique to clean the environment via microorganisms, for example, the bacteria Oleispira (clean oil spills). Mycoremediation - Use fungi in the decontamination of pollutants, for example, the use of fungal-mycelia in bioremediation.
Algae is used to produce biofuel and also removes pollutants from contaminated water. Lichens - These are the indicators of a healthy environment. Protozoa - It plays a role in the environmental food web dynamics.

Chemotropism causes growth of pollen tubes towards ovules. Plants grow towards or away from the light, the type of tropism in the response to light is called Phototropism. For Example, Sunflowers grow in accordance with the response of the sun.
The downward growth of roots is negative Geotropism. Hydrotropism is a plant's (especially roots) to a stimulus or gradient in water concentration that determines the direction of growth. Example : Tomato root.

Chemotropism causes growth of pollen tubes towards ovules. Plants grow towards or away from the light, the type of tropism in the response to light is called Phototropism. For Example, Sunflowers grow in accordance with the response of the sun.
The downward growth of roots is negative Geotropism. Hydrotropism is a plant's (especially roots) to a stimulus or gradient in water concentration that determines the direction of growth. Example : Tomato root.

Stomata: Tiny, microscopic pores used to exchange the gasses by closing and opening the pores in the leaves. Grana (thylakoid membrane): is the site where light reactions of photosynthesis occur.
Thylakoids are the internal membranes of chloroplasts and cyanobacteria, and provide the platform for the light reactions of photosynthesis. Chlorophyll: It is the pigment that gives plants their green color.

Sclerenchyma: It is a simple permanent tissue. Cells are long with tapering ends and have a thick cell wall made of lignin. These cells are generally dead and do not contain protoplasm.
Guard cells are pairs of epidermal cells that control gas diffusion by regulating the opening and closure of stomatal pores. Parenchyma is a type of simple permanent tissue that makes a major part of ground tissues in plants, where other tissues like vascular tissues are embedded.
Collenchyma is a supporting tissue characteristic of the growing organs of many herbaceous and woody plants.

Stomata are the specialized openings present in the epidermis of plant cells. It has a stoma, which is a tiny pore surrounded by guard cells. They aid in the flow of gasses between the atmosphere and plants.
Guard cells regulate the opening and closing of stomatal holes, which are controlled by osmosis. The stomata close when the guard cells lose water and constrict becoming flaccid and straight.

Suberin - A wax-like organic fatty substance found in cork walls. It acts as a barrier to movement of water and solutes.
Cellulose - A complex carbohydrate and basic structural component of plant cell walls.
Cutin - A waxy polymer and main component of plant cuticles which covers all aerial surfaces of plants.
Lignin - Key structural materials in the support tissues of most plants. Suberin is a complex polyester that, together with cutin and lignin, forms a physical barrier in land plants.

Dedifferentiation process - Permanent cells that have lost their ability to divide. Redifferentiation process - Cells, which had regained their ability to divide, again lose that ability and mature into permanent tissue to perform their specialized functions.
Development - Cell division, elongation of cells, differentiation, maturation etc. Proliferation - An increase in the number of cells as a result of cell growth and cell division. Regeneration - Regeneration of a growth structure lost by injury.

In humans anaerobic respiration happens in muscles during hard exercise. In the process of fermentation, glucose is oxidized partially to produce acids and alcohol. It is also an anaerobic process. The microbes like yeast break down the food, that is, glucose into carbon dioxide, and ethanol, and discharge energy in the absence of oxygen.

Transpiration - Process of elimination of excess water from the plant body. Stomatal Transpiration - The water near the surface of the leaves changes into vapor and evaporates when the stomata are open.
Present in all plants. Lenticular Transpiration - Evaporation through Lenticels (minute openings in the bark of branches and twigs). Not present in all the plants.
Cuticular Transpiration - Evaporation of water from the cuticle (a waxy covering on the surface of the leaves of the plants). Transpiration decreases in high humidity conditions.