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Stimulus. A stimulus is anything that can trigger a physical or behavioural change. The plural of stimulus is stimuli. Examples of stimuli include irritants, sights, sounds, heat, cold, smells, or other sensations. Life processes . M- movement - response to stimuli
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Stimulus A stimulus is anything that can trigger a physical or behavioural change. The plural of stimulus is stimuli. Examples of stimuli include irritants, sights, sounds, heat, cold, smells, or other sensations.
Life processes • M- movement - response to stimuli • R- Reproduction - Mitosis and Meiosis • S- Sensitivity – response to stimuli • N- Nutrition – response to stimuli /movement • E- Excretion • R- Respiration • G- Growth – Mitosis and Meiosis
Survival of an organism depends on its ability to respond to a stimulus whether it’s a plant or an a animal
Why is it important for organisms tobe able to respond to a stimulus ? What type of stimulus might they respond to and why ? 1. Heat 2.pH 3.light 4.Moisture
Growth and reproduction • Watch the video clip Mitosis • Look out for the terms • 1. Diploid- • 2. Haploid-
Germination –growth of a seed • Watch the video clip on Growth
Growing plants • In order to reproduce, flowering plants produce seeds. • All seeds contain an embryo and a food store containing starch.
Embryo plant which grows into bean plant Protects internal structure Seed coat Young shoot Young root Seed coat Removed and seed opened out 2 Seed leaves (cotyledons) Food store full of starchy food
Copy table and fill in missing answers • Answer the following questions in sentences! • What kind of food is stored in a seed? • What happens to the food stored in the seed leaves (cotyledons) when germination starts?
GERMINATION The development of a plant embryo into an independent plant
First green leaves Young shoot Soil level Young root Root hair Side roots
The Golden rules of experimental design At each stage only ___ ______ _____ is studied at a time because if several are involved then it is impossible to know which is responsible for the results one variable factor ____ _________ are used because if only a few are used then perhaps these were unusual and not typical of the species in general Many organisms This experiment should be repeated ____ _____ because if not then perhaps the outcome just happened to result from a lucky chance many times
1 2 3 4 control WATER WATER WARMTH WATER WARMTH OXYGEN OXYGEN WARMTH NO OXYGEN NO WARMTH NO WATER OXYGEN
1 2 3 4 control WATER WATER WARMTH WATER WARMTH OXYGEN OXYGEN WARMTH NO OXYGEN NO WARMTH NO WATER OXYGEN
Seeds need _____, ______ and ______ for germination. ______ is needed for respiration to give ______ for growth. _____ is needed to allow ________ to digest stored food for the growing embryo ______ is needed to give a suitable ___________ for enzymes to act. water warmth oxygen Oxygen energy Water enzymes Warmth temperature