YTSS PURE BIO 3

NAME: ( ) CLASS: YISHUN TOWN SECONDARY SCHOOL PRELIMINARY EXAMINATION 2024 SEC 4 EXPRESS BIOLOGY (6093/1) DATE : 28 August 2024 DAY : Wednesday DURATION : 1 hr MARKS : 40 marks ADDITIONAL MATERIALS Multiple Choice Answer Sheet (OMS) READ THESE INSTRUCTIONS FIRST Write your name, class and register number in the spaces provided at the top of this page and on the OMS. There are forty questions. Answer all questions. For each question, there are four possible answers, A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the OMS answer sheet. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in this booklet. You may use an approved calculator. This question paper consists of 17 printed pages

2 1 The diagrams below are organelles found inside cells. Which row identifies the typical distribution of these organelles? plants only animals and plants A 3 1, 2, 4 B 4 1, 2, 3 C 1, 4 2, 3 D 3, 4 1, 2 2 Which substances are not produced at the ribosomes? 1 amino acids 2 amylase 3 glycerol A 3 only B 1 and 2 C 1 and 3 D 2 and 3 3 The graph shows the concentrations of different ions inside and outside of an animal cell. Which process is directly responsible for the net movement of K + and Mg2+ ions into the animal cell? A absorption B active transport C diffusion D osmosis

3 4 The diagram shows a permeable tubing filled with salt solution in a test-tube of water. Which graph shows the changes in salt concentration inside and outside the tubing after 24 hours? 5 Two samples of food are tested. The results are shown in the table. sample results iodine test Benedict’s test biuret test X brown orange blue Y blue-black blue violet What do these results show? A Sample X contains reducing sugars and starch. B Sample X contains starch only. C Sample Y contains protein and starch. D Sample Y contains protein only.

4 6 The table shows the percentage of carbon, hydrogen, nitrogen and oxygen atoms in three molecules, X, Y and Z. molecule percentage of atoms / % carbon hydrogen nitrogen oxygen X 25.0 50.0 0.0 25.0 Y 28.5 42.7 8.0 20.8 Z 35.0 61.6 0.0 3.4 Which correctly identifies molecules X, Y and Z? X Y Z A fat protein glucose B glucose protein fat C protein glucose fat D protein fat glucose 7 In an enzymatic reaction, where is the active site located and what represents the lock and the key? active site lock key A on the enzyme substrate enzyme B on the enzyme enzyme substrate C on the substrate enzyme substrate D on the substrate substrate enzyme 8 The diagram shows a transverse section of an intestinal villus. Which correctly shows the substances transported by vessels X and Y? vessel X vessel Y A amino acids glucose B fats amino acids C glucose water D amino acids fats

5 9 The diagram shows a section through a mammalian heart. Which vessel would be the first to receive nicotine that is absorbed into the bloodstream through the lungs of a cigarette smoker? 10 The graph shows the changes in the blood pressure during one cardiac cycle. Which row describes the ventricle and the semi-lunar valve at X? ventricle semi-lunar valve A contracting closing B contracting opening C relaxing closing D relaxing opening tricuspid valve bicuspid valve A B C D

6 11 The diagram shows some capillaries and tissue cells. Which row describes what is happening at points 1 and 2? 1 2 A fluid passes out of the capillary carbon dioxide enters the blood B oxygen leaves the blood glucose enters the blood C proteins leave the blood water enters the blood D urea leaves the blood fluid passes into the capillary 12 Annie, Belinda and Caleb are siblings. Caleb can donate blood to his two sisters. Annie can receive blood from both Belinda and Caleb. When the serum of blood type B is added to a sample of Belinda’s blood, agglutination occurs. What are the blood types of the siblings? Annie Belinda Caleb A AB A O B O B AB C O A AB D AB B O 13 The graph shows the oxygen uptake of a man before, during and after strenuous exercise. Which region of the graph represents the repayment of oxygen debt? oxygen uptake time A B C D

7 14 A person blows into the mouthpiece for a short period of time, as shown in the diagram. Which row is correct? limewater in tube X limewater in tube Y A remains clear remains clear B remains clear turns cloudy C turns cloudy remains clear D turns cloudy turns cloudy 15 The graph shows the changes in the pressure and the volume inside the lungs during one complete breath. At which point are the internal intercostal muscles starting to contract? mouthpiece limewater tube Y tube X pressure in lungs volume of lungs / dm3 0 1 2 3 time / s time/ s A B C D pressure volume 2.0 2.5

8 16 The diagram shows some substances found in the human body. Which area of the diagram represents the products of anaerobic respiration? 17 Which graph, A, B, C or D, shows the effect on urea concentration in the blood after removing a mammal’s kidneys at time X and its liver at time Y? lactic acid energy carbon dioxide A B D C concentration of urea in blood concentration of urea in blood X Y time time X Y concentration of urea in blood X Y X Y time time concentration of urea in blood A B C D

9 18 Which graph shows the change in concentration of molecules in the dialysis fluid during kidney dialysis? 19 The diagram summarises the process of homeostasis. Which numbered arrows represent the effect of negative feedback? A 1 and 2 only B 1 and 4 only C 2 and 3 only D 2 and 4 only normal level detector measures the increase and effector activated detector measures the decrease and effector activated increase normal level decrease 1 2 3 4 increasing level decreasing level

10 20 Which of the following may cause diabetes mellitus? A blocked pancreatic duct B damaged cells in pancreas C sugar in urine D sugar in blood 21 A local anaesthetic is a drug used to block nerve impulses. The diagram represents part of the nervous system. X, Y and Z show sites where the anaesthetic can be injected. In an experiment, one person can feel a pin prick his leg but cannot move his leg. Where was the anaesthetic injected in this person? A at X B at Y C at Z D at both X and Y 22 The graph shows changes in the shape of the lenses of a person’s eyes while watching a bird flying. At which point is the bird flying most rapidly towards the person? Y Z X