Biology (Part-VII) (Railway)

• Pistil is the female reproductive part. It consists of style, stigma and ovary.

• Organisms that die and decay organic matter are used as food in saprophytic nutrition.

• Other examples of saprophytes include fungi, yeast, and numerous types of bacteria.

• Biodegradable substances have biological origin and include organic wastes.

• Since paper is prone to decomposition by microbial action, it is considered as a biodegradable waste.

• Gills are the respiratory organs of fish that allow them to breathe in water.

• As the fish opens its mouth, water runs over the gills, and blood in the capillaries picks up oxygen that's dissolved in the water.

• They promote cell division, or cytokinesis, in plant roots and shoots.

• Cytokinin is most concentrated in the youngest parts of the plant, such as the seeds, fruits, young leaves and root tips.

• In the F2 generation Mendel found that 3 plants are taller, and one plant was short (dwarf).

• Due to the segregation process F2 generation indicates genotype ratio 1:2:1 in a monohybrid crossing.

• Here phenotype can be either 3:1 ratio ог 1:2:1 ratio depending on types of the genes.

• It surrounds the plasma membrane of plant cells and provides tensile strength and protection against mechanical and osmotic stress.

• It also allows cells to develop turgor pressure, which is the pressure of the cell contents against the cell wall.

• Kidneys- It not only excretes wastes but also regulates blood volume and pressure.

• Ureter- They are paired, narrow, tubular structures which open into the urinary bladder.

• Urinary bladder It temporarily stores urine.

• Urethra- It is a canal-like structure which extends from the floor of the bladder to the exterior.

• Chemical method: Pill

• Device: Copper-T

• Plants get rid of excess water by transpiration and guttation.

• Transpiration is evaporative loss of water from plant leaves through stomata.