In: Biology
12. When body requires more glucose than that is provided by diet then liver starts gluconeogenesis. It is a process in which various non carbohydrate products are used to synthesize glucose. Pyruvate, lactate, various glucogenic amino acids( like alanine, aspartate,glycine), propionate are some of the non carbohydrate products that can be used for gluconeogenesis.
13. Fats specially triacylglycerols serve as the fuel reserve of the body. Fats act as an insulating material in the body that help in maintaining the body temperature. Fat helps as a protective covering for various important internal organs. Fats in the form of phospholipids and glycolipids are important constituents of the cell membrane.
14. Liver helps in converting ammonia to urea which is then transported to kidney where they are excreted through urine. Conversion of ammonia to urea occours via the urea cycle . The first two enzymes of this cycle namely carbamoyl phosphate synthase I and ornithine transcarbamoylase are present in the mitochondrion and the other three namely arginosuccinate synthase , arginosuccinase and arginase are present in the cytosol.
15. 1gram of fat provides 9 calories of energy on the other hand 1 gram of carbohydrate gives 4 calories of energy after their complete breakdown. That is why the body stores fat rather than carbohydrates as their energy source.