20 (a) Fallopian tube / Oviduct 1 (b) Gonorrhoea or syphilis 1 (c) Placenta is disc – like structure that connects and provides nutrition to the 1 developing foetus inside the uterus and also helps in excretion. (d) Menarche is the beginning of menstrual cycle attaining reproductive age in ½ female. Menopause is the end of the menstrual cycle and reproductive age. ½ (e) Any mammal like human , dog , cat etc. 1 21 (a) (b) Glycolysis is the conversion of 6-C glucose into 3-C pyruvate inside the cytoplasm. (c) Does not allow mixing of oxygenated blood with de-oxygenated blood giving better respiratory efficiency and energy requirement to maintain constant body temperature in mammals. 3 1 1 22 1+1 23 To remove the oxide layer formed due to corrosion , so that it burns easily. 1 Combination reaction . 1 OR (a) It will be basic in nature . 1 (b) Calcium carbonate. 1 24 12 Ω and 4 Ω in parallel 1/12 + 1/4=( 1 + 3) / 12 = 4/12 = 3 Ω 1 + 1 3 Ω + 2 Ω (in series) = 5 Ω 25 CuSO4 – Copper sulphate aqueous solution 1 CuSO4 + Zn ------ ZnSO4 + Cu ½ Blue colourless ½ 26 Any two differences
20 (a) Fallopian tube / Oviduct (b) Gonorrhoea or syphilis (c) Placenta is disc – like structure that connects and provides nutrition to the developing foetus inside the uterus and also helps in excretion. (d) Menarche is the beginning of menstrual cycle attaining reproductive age in female. Menopause is the end of the menstrual cycle and reproductive age. (e) Any mammal like human , dog , cat etc. 1 1 1 ½ ½ 1 21 (a) (b) Glycolysis is the conversion of 6-C glucose into 3-C pyruvate inside the cytoplasm. (c) Does not allow mixing of oxygenated blood with de-oxygenated blood giving better respiratory efficiency and energy requirement to maintain constant body temperature in mammals. 3 1 1 22 1+1 23 To remove the oxide layer formed due to corrosion , so that it burns easily. Combination reaction . OR (a) It will be basic in nature . (b) Calcium carbonate. 1 1 1 1 24 12 Ω and 4 Ω in parallel 1/12 + 1/4=( 1 + 3) / 12 = 4/12 = 3 Ω 3 Ω + 2 Ω (in series) = 5 Ω 1 + 1 25 CuSO4 – Copper sulphate aqueous solution CuSO4 + Zn ------ ZnSO4 + Cu Blue colourless 1 ½ ½ 26 Any two differences