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RECEPTION, RESPONSE AND COORDINATION

Introduction Irritability Stimuli Response Co-ordination Reception Irritability in Plants Tropisms Tactic Movement in Plants and Other Organisms Nastic Movements Production of Auxins and their Effects on Plant Growth Reception, Responses and Coordination in Animals Receptors Effectors The Nervous System Simple And Conditioned Reflex Actions The Role of Endocrine System in Human Beings Comparison between Endocrine and Nervous System Structure and Function of Parts of the Human Eye Structure and Functions of Parts of the Human Ear Practical Activities To Investigate Tactic Responses To Investigate Tropisms in Plants Experiment to Determine Distance of the Blind Spot The Knee Jerk Experiment\ Introduction The structures involved in detecting the changes may be located far away from the ones that respond. There is need for a communication system within the body. The nervous system and the endocrine system perform this function, i.e. linking the parts of the body that detect changes to thos...

KCSE 2018 Biology Paper 1 (231/1) Marking Scheme

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KCSE Past Papers 2018 Biology Paper 1 (231/1) Kenya Certificate of Secondary Education 2018 Biology Paper 1 Answer all the questions in the spaces provided. 1. (a) Name the cell organelle found in abundance in the white blood cells.(1 mark) (b) Give a reason for your answer in (a) above.(1 mark) 2. State two observable features that place a millipede into its Class. (2 marks) 3. Which sets of teeth would be used in chewing sugarcane for maximum extraction of sap? (2 marks) 4. A group of font two students placed a fresh leaf in warm water. They observed that air bubbles formed on the surface of the leaf. (a) What biological process were they investigating?(1 mark) (b) Name the structures from which the air bubbles were coming from. (1 mark) (c) Explain the distribution of the structures named in (b) above on the leaf surfaces of a land plant. (2 marks) 5. State why it is important for plants to lose water to the atmosphere.(3 mark) 6. The diagram below illustr...

KCSE Past Papers 2018 Biology Paper 2 (231/2)

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The Kenya National Examinations Council  Kenya Certificate of Secondary Education 231/2 - Biology - Paper 2 Nov. 2018 - 2 hours Answer all the questions in the spaces provided. SECTION A (40 marks) Answer all the questions in this section in the spaces provided. 1. The diagram below illustrates a section of the mammalian kidney. (a) Name the structures labelled E and F. Region H (1 marks) E ...........(1 marks) F...........(1 marks) (b) Explain the processes that take place in the regions labelled G and H. Region G(3 marks) Region H(3 marks) 2. Below is a graphical representation of students’ height in a classroom. (a) Name the type of curve illustrated. (b) (i) State the type of variation represented by the curve. (ii) State two meiotic processes that lead to variation among organisms. (2 marks) (iii) Explain the role of variation in organisms.(2 marks) (c) EKplain the need for genetic counselling in present day health facilities. (2 marks)...