A flower develops on a branch from a bud. A flower is the reproductive part of the plant. A stalk called the pedicel attaches the flower to the branch. The upper swollen end of the pedicel is called ‘thalamus’. Thalamus bears floral parts like – Sepals, Petals, Stamens and Pistil (carpel).
The bones of our skeleton system are hard and cannot bend. But, because of joints we can bend, and rotate our limbs. It is possible due to joints. The place in our body where bones meet each other is called as joint. It helps in walking, running, swimming, skipping etc. like movements. There are different types of joints in our body. But the main four types of joints have been discussed here.
(i) Fixed Joint (ii) Pivotal Joint (iii) Ball and Socket Joint (iv)Hinge Joint
The process of separating of insoluble solids from liquid in its solution is done by sedimentation, decantation and filtration. These are interrelated processes.
We choose any object/product on the basis of their properties and uses. The important properties of the objects can be – Appearance, hardness, solubility, sinking or floating nature, transparency, malleability, ductility, conductivity and combustibility.
Reproduction, Asexual Reproduction, Budding, Buds, Binary Fission, Sexual Reproduction, Male reproductive organs, Sperms, Male gametes, Female Reproductive organ, ova (eggs), Female gamete, Fertilization, Internal Fertilization, External Fertilization, Zygote, Embryo, Foetus, I.V.F. ( In vitro fertilization), Test tube babies, Oviparous animals, Viviparous animals, Metamorphosis, Tadpole (larva), Cloning, Dolly Sheep
Coal- It is a hard stone like black coloured solid fossil fuel. It is used for cooking food. Steam based railway engine used coal to produce steam for running pistons. In thermal power plants, coal is used to generate electricity. Different industries use coal as a fuel. Petroleum (Petra-Rock; oleum=oil)-Petrol and diesel like oils are obtained from petroleum. Petroleum is formed by the carbonization of fossils of animals and tiny plants like planktons. It is found in between the layers of impervious rocks inside the earth. It is found at a depth of few kilometers to few hundred kilometers. Petroleum is a dark oily liquid. It has unpleasant odour. It is a mixture of different hydrocarbons.
The percentage of nitrogen in the atmosphere is 78 %. Nitrogen is very essential for living organisms as it is a constituent of proteins, vitamins, Chlorophylls, nucleic acids like D.N.A and R.N.A. The atmospheric nitrogen cannot be taken directly by plants and animals. Certain bacteria and Cynobacteria (blue green algae) fix the atmospheric nitrogen in the soil in form of nitrogenous compounds. In factories when chemical fertilizers are prepared and also during lightening, nitrogen is fixed in nitrogenous compounds.