science 12 grade

Question: The concentration of urea is highest in 1. renal vein 2. hepatic portal vein 3. dorsal aorta 4. hepatic vein Answer: ..

Question: The fluid between the retina and the lens is called _______. 1. aqueous humour 2. vitreous humour 3. aqua 4. humus Answer: ..

Question: A non-enzyme protein present in the saliva is _________. 1. heparin 2. mucin 3. ptyalin 4. none of the above Answer: ..

Question: Radius of curvature of a concave mirror is always _____ to the mirror. 1. parallel 2. perpendicular 3. inclined at 60 o 4. inclined at 45 o Answer: ..

Question: The fertilization of human egg by the sperms takes place in __________________. 1. ovary 2. oviduct 3. vagina 4. uterus Answer: ..

Question: The radiations absorbed by ozone layer are ______. 1. infra-red 2. ultra-violet 3. visible 4. gamma rays Answer: ..

Question: What are Biosphere reserves? Answer: Biosphere reserves are multipurpose protected areas with major objectives such as: Conservation of diversity and integrity of plants Promotion of ecological conservation Creation of awareness about environmental aspects and eco frien..

An element is defined as a pure substance as it is made up of only one kind of atoms having the same atomic number. The smallest particle of an element is the atom, which has all the properties of that element. It cannot be further reduced to simpler substances by ordinary physical or chemical pro..

The atomic number of an element is 12. How many protons and electrons are there in the ato..

. In 1793, he left for Manchester to teach physics and chemistry in a college. In 1801, he observed and discovered the law of expansion of gases on heating. He also enunciated the law of partial pressures and found methods of determining vapour pressure of gases. He invented the dew point hygromete..