Science 2
- Cell division is one of the important properties of cells and organisms. Cell division is an important property because growth, repair, reproduction and continuity of life all depend on it. Growth: a multicellular... 1
- Fibers are one of the important nutrients. Fibres are important nutrients because, although they are not digested, they keep the digestive system healthy. Fibres (roughage) are the in... 1
- Oxygen is necessary for complete oxidation of glucose. Oxygen is necessary because it is the final acceptor of electrons and hydrogen in the electron transfer chain; without it glucose cannot be... 1
- Distinguish between c. Aerobic and anaerobic respiration. Aerobic respiration needs oxygen and oxidises glucose completely; anaerobic respiration occurs without oxygen and oxidises it only partly. A... 1
- distinguish between b. Mitosis and meiosis. Mitosis produces two identical diploid cells for growth and repair; meiosis produces four haploid gametes with variations. MitosisMeiosis Oc... 1
- Distinguish between a. Glycolysis and TCA cycle. Glycolysis breaks glucose into pyruvic acid in the cytoplasm, while the TCA (Krebs) cycle completely oxidises acetyl-CoA to CO₂ in the mitoc... 1
- Write defination f. Glycolysis. Glycolysis: the first step of cellular respiration, in which one molecule of glucose is broken down step by step into two molecules of pyruv... 1
- Write definations e. Aerobic respiration. Aerobic respiration: cellular respiration that takes place in the presence of oxygen, in which glucose is completely oxidised to carbon diox... 1
- Write defination d. Cellular respiration Cellular respiration: the process in which food molecules (mainly glucose) are oxidised inside the cells to release energy, which is stored... 1
- Write definations c. Proteins. Proteins: large, complex molecules made of many amino acids joined by peptide bonds; they are body-building nutrients. Proteins are needed f... 1
- Write definations b) Nutrients Nutrients: the substances in food that the body uses to obtain energy, and for growth, repair and control of body functions. Main nutrients... 1
- Write definitions. a. Nutrition. Nutrition: the process of taking in food and using it to obtain energy and materials for growth, repair and maintenance of the body. It incl... 1
- Fill in the blanks and explain the statements. a. After complete oxidation of a glucose molecules, ---- --- --- number of ATP molecules are formed. a. 38; b. 2 (pyruvic acid); c. pachytene; d. metaphase; e. phospholipid; f. anaerobic a. After complete oxidation of one glucose molecule, 3... 1
- Write evolutionary history of modern man. The evolutionary history of modern man: Approximately 7 crore years ago, the dinosaurs disappeared completely. At that time, monkey-like ani... 1
- Define fossil. Explain importance of fossils as proof of evolution Fossils offer palaeontological evidence for the evolutionary process. Due to some natural calamities the organisms get buried during ancient... 1
- Explain with suitable examples importance of anatomical evidences in evolution Anatomical evidences show that organisms which look different and do different work have the same basic internal structure, which means they... 1
- Explain the theory of evolution and mention the proof supporting it The theory of evolution says that present-day organisms have developed gradually from simpler ancestors over a very long time, and the main... 1
- Explain the process of formation of complex proteins. Complex proteins are formed by protein synthesis, which takes place in three steps: transcription, translation and translocation, followed b... 1
- How are the hereditary changes responsible for evolution? Answer: Hereditary changes (variations in genes) are passed from parents to offspring. Over many generations, useful variations accumulate i... 1
- Define vestigial organs. Write names of some vestigial organs in human body and write the names of those animals in whom same organs are functional. Vestigial organs are organs that are reduced and non-functional (useless) in an organism, but are fully developed and functional in some oth... 1
- Define heredity. Explain the mechanism of hereditary changes. Heredity is the transfer of characters (traits) from parents to offspring, generation after generation. Hereditary changes arise when the ge... 1
- short note on Connecting link Some plants and animals show some morphological character by which they can be related to two different groups they can be called connecting... 1
- short note on Evolution Evolution is the gradual change in living organisms over a very long period of time, by which new species are formed from earlier ones. Life... 1
- short note Embryology. Comparative study of embryonic developmental stages of various vertebrates show extreme similarities during initial stages and those similar... 1