PREFACE. N-LEVEL TOPICAL SCIENCE (BIOLOGY) provides a thorough revision for students taking the GCE N-Level Science (Biology) Examination.

Transcription

1 PREFACE N-LEVEL TOPICAL SCIENCE (BIOLOGY) provides a thorough revision for students taking the GCE N-Level Science (Biology) Examination. This book contains: Useful Notes Students are able to revise their work before attempting the questions. This will help students recall important theories, formulae and concepts that they have learnt. Past Examination Questions Questions from past examinations provide the best practice. Students are able to apply what they have learnt. At the same time, they are also provided with an insight into the type and style of questions often asked in an examination. Latest Examination Papers The latest examination papers are included for extra practice, providing the students with an idea of what is expected of them in the actual examination. Answers Answers are provided for reference and self-study purposes. Questions from past examinations have been carefully classified into the relevant topics. This will enable students to revise and practise systematically. Students are advised to study each topic before attempting an exercise. These exercises will then be effective in reinforcing the students understanding of all the topics learnt. W. Leong (B. Sc., Hons., Dip. Ed.)

2 CONTENTS N-LEVEL SCIENCE (BIOLOGY) SYLLABUS... (i) - (vii) THEME I PRINCIPLES OF BIOLOGY Topic 1A Cell Structure and Organisation I... (1A)1-7 Plant and Animal Cells Topic 1B Cell Structure and Organisation II... (1B)1-11 Specialised Cells, Tissues and Organs Topic 2 Movement of Substances... Diffusion Osmosis (2)1-8 Topic 3 Biological Molecules... Water and Living Organisms Carbohydrates, Fats and Proteins Enzymes (3)1-19 THEME II MAINTENANCE AND REGULATION OF LIFE PROCESSES Topic 4 Animal Nutrition... Human Alimentary Canal Chemical Digestion Absorption and Assimilation Topic 5 Plant Nutrition... Leaf Structure Photosynthesis Topic 6 Transport in Flowering Plants... Water and Ion Uptake Transpiration and Translocation Topic 7 Transport in Humans... Circulatory System Topic 8 Respiration... Human Gaseous Exchange Aerobic Respiration Anaerobic Respiration (4)1-15 (5)1-14 (6)1-9 (7)1-19 (8)1-17 THEME III CONTINUITY OF LIFE Topic 9A Reproduction in Plants... Asexual Reproduction Sexual Reproduction in Plants (9A)1-5 Topic 9B Reproduction in Humans... (9B)1-15 Male and Female Reproductive Systems Topic 9C Sexually Transmitted Diseases... Spread and Control of the Human Immunodefi ciency Virus (HIV) (9C)1-3 N LEVEL SCIENCE BIOLOGY SEP/OCT 2009 PAPERS 5 & 6... (2009)1-19 ANSWERS (separate booklet) Topics 1A-9C, Papers 5 & 6 Latest Examination Papers

3 THEME I: PRINCIPLES OF BIOLOGY TOPIC 1A CELL STRUCTURE AND ORGANISATION I Plant and Animal Cells SYLLABUS OBJECTIVES (a) identify organelles of typical plant and animal cells from diagrams, photomicrographs and as seen under the light microscope using prepared slides and fresh material treated with an appropriate temporary staining technique: chloroplasts cell membrane cell wall cytoplasm cell vacuoles (large, sap-filled in plant cells, small, temporary in animal cells) nucleus (b) identify the following organelles from diagrams and electronmicrographs: mitochondria ribosomes (c) state the functions of the organelles identified above. (d) compare the structure of typical animal and plant cells. USEFUL NOTES 1A.1 DIAGRAMS OF CELLS (a) TYPICAL ANIMAL CELL: CHEEK CELL cell membrane nucleus cytoplasm (b) ELECTRONMICROGRAPH OF ANIMAL CELL mitochondrion ribosome (1A)1

4 (c) TYPICAL PLANT CELL: ELODEA LEAF CELL large central vacuole nucleus cytoplasm starch granule cellulose cell wall cell membrane (d) ELECTRONMICROGRAPH OF PLANT CELL mitochondrion chloroplast ribosome 1A.2 CELL ORGANELLES (a) Cell Wall : Cell wall is the outer-most layer of a plant cell. It is permeable and allows all substances in a solution to pass through it. It is made of cellulose. (b) Cell membrane : Cell membrane is the outer-most layer of an animal cell and the second layer of a plant cell. It is semi-permeable and allows only some substances in a solution to pass through it. It is made of fats and proteins. (c) Nucleus : The nucleus is enclosed by a nuclear membrane that is semipermeable. It controls the life processes of the cell. Inside it are chromosomes that are made of DNA. DNA (deoxyribonucleic acid) carry genetic code from the parents to their offspring. (d) Cytoplasm : Cytoplasm is the living jelly-like material, excluding the nucleus, in a cell. Protoplasm is the term used to include cytoplasm and nucleus. (e) Vacuole : Vacuole is a transparent body in the cytoplasm. It contains a liquid called cell sap. (f) Chloroplasts : Plant cells have green granules in the cytoplasm called chloroplasts. Chloroplasts contain green pigment called chlorophyll. Chlorophyll can absorb energy from sunlight for photosynthesis. (g) Mitochondria : Mitochondria are rod-shaped organelles in the cytoplasm. They are involved in the production and release of energy from food substances such as glucose during cellular respiration. (h) Ribosomes : Ribosomes are organelles that carry out protein synthesis. (1A)2

5 1A.3 DIFFERENCES BETWEEN A TYPICAL ANIMAL AND PLANT CELL Animal cell Absence of cell wall Absence of chloroplast Presence of many small temporary vacuoles Plant cell Presence of cell wall Presence of chloroplasts Presence of large central vacuole PAPER 5 Each question below is provided with four answers. Select the correct answer and write A, B, C or D in the brackets provided. 1. The diagram shows a plant cell. Which parts of the cell are composed of living material? (2000 P5 Q1) 1 A 1 and 3 2 B 1 and 4 C 2 and 3 3 D 2 and 4 4 ( ) 2. The diagram shows a cell from a leaf. Which two structures are present in a leaf cell but not in an animal cell? (2001 P5 Q1 / 2006 P5 Q1) A cell membrane and chloroplast B cell membrane and cytoplasm C cell wall and chloroplast D cell wall and cytoplasm ( ) 3. The diagram shows an animal cell. What is X? (2002 P5 Q1) A Chloroplast B Cytoplasm X C Cell membrane D Nucleus ( ) (1A)3

6 4. The diagram shows three plant cells. Which features are found in all three cells? (2004 P5 Q1) A Chloroplasts and cell wall C Nucleus and large vacuole B Cell wall and nucleus D Large vacuole and chloroplasts ( ) 5. The diagram shows two cells. Which two parts are found in both cells? (2005 P5 Q2) A cell membrane and cell wall B cell wall and vacuole C vacuole and nucleus D nucleus and cell membrane 6. The diagram shows an animal cell and a plant cell. ( ) Which parts are found in both cells? (2008 P5 Q2) A cell membrane and cell wall B cell wall and vacuole C vacuole and nucleus D nucleus and cell membrane ( ) (1A)4

7 PAPER 6 SECTION A Answer the following questions in the spaces provided. 1. The diagrams show a plant cell and an animal cell. diagram 1 diagram 2 (a) Using the dotted lines provided on the diagrams, name A, B and C. [1] (b) Complete the following statements to say which of the two diagrams is a plant cell and which is an animal cell. Diagram 1 is cell. Diagram 2 is cell. [1] (c) Name two structures shown that are found only in plant cells [1] (d) Which one of the following processes takes place in both cells? Tick the correct box. fertilisation photosynthesis transpiration respiration [1] (2003 P6 Q1) (1A)5