Formatting page ...
Page 1 of 2 CENTRAL MODERN SCHOOL Half Yearly Examination, Session : 2020 2021 Class X BIOLOGY Time : 2 hrs. (+ 15 mins. RT) F.M. : 80 ( You are advised to write the answers within (1) 8 page booklet and (1) continuation sheet ) SECTION I (40 Marks) (Attempt all questions from this section) [You should not spend more than 1 hour in this section.] Question : 1 a) Name the following : [5] i) Minute openings on woody stems. ii) The pigment causing clear yellow colour of urine. iii) The muscle fibres between AV Node and interventricular septum. iv) The substances having strong affinity for water. v) The force which causes the water to stick to the inner surface of the xylem cells. b) Mention the exact location of : [5] i) Papillary Muscles ii) Hydathodes iii) Pulvinus iv) Pericardial Fluid v) Spleen c) Correct and rewrite the statements by changing the underlined words only : [5] i) Osmosis is multi-directional. ii) Mitosis occurs in testis to produce sperms. iii) Monocytes produce antibodies to neutralise the toxic effect of germs. iv) Oxygen released during photosynthesis is obtained from CO2 . v) DUP sound is produced during closure of atrio-ventricular valves. d) Write down the function of : [5] i) Chordae tendinae ii) Centromere iii) Cuticle iv) Tricuspid valve v) Ureter e) Choose the correct word from the brackets and rewrite the statements : [5] i) The smallest united branch of capillaries is . (arteriole, venule, vein). ii) Urea is produced in (liver, kidney, small intestine). iii) Food is transported in plants in the form of (glucose, starch, glycogen). iv) . (RNA, DNA, RNA & proteins) is mainly synthesized during S-Phase of cell cycle. v) Lymph is ultimately poured into ( Pulmonary vein, Precaval vein, Postcaval vein). f) Identify the odd term and name the category of the remaining terms : [5] i) Adenine; Histone; Guanine; Thymine. ii) Biconcave ; Large nucleus; Haemoglobin; 7micron diameter. iii) Sunlight; Wind Velocity; High Temperature; Humidity. iv) Carbon Dioxide; Urea; Uric Acid; Ammonia. v) Pulmonary Artery; Vena Cava; Tricuspid Valve; Bicuspid Valve. g) Give suitable reasons for the following : [5] i) Osmosis is referred to as passive transport. ii) Blood samples are collected from veins and not from arteries. iii) Meiosis is called as reduction division. iv) Blood pressure is very high in the kidneys. v) Overuse of fertilisers might kill the plants. h) Expand the following : [5] i) ADH ii) NADPH iii) DCT iv) SAN v) RNA SECTION II (40 marks) (Attempt any four questions) [ Do not spend more than 1 hour in this section ] Question : 2 a) i) Draw a diagram to show cytokinesis in plant cells. ii) How does it differ between plant and animal cells ? iii) In which phase of cell division does cytokinesis start ? [5] Contd......Page 2
|
