NOTE

SCIENCE - YEAR 5
INVESTIGATING LIVING THINGS
1.   MICROORGANISMS 1.1   Microorganisms are living things, they are also known as microbes. 1.   The following are some types of microorganisms.     2.   All microorganisms breathe. 3.   Like all microorganisms, bread mould grows. 4.   Some microorganisms move. 5.   Microorganisms are very small.  They cannot be seen with naked eye.  We have to             use a microscope to see microoranisms. Magnifying glass can be used to observe        certain microorganism such as yeast.                                                                                                                       Magnifying glass                                                                                  Microscope  1.2  Harmful and useful microorganisms 1.   Many microorganisms are very harmful but some are useful to human.  Useful microorganisms are used in the following processes.                                                  2.   Pathogens       Microorganisms that caused diseases are called pathogens.  Some of        the diseases caused by pathogens are as shown below:              3.   Some ways to prevent diseases.  Keeping ourselves and surrounding clean can prevent many disease caused by microorganism.  . 2.   SURVIVAL OF THE SPECIES 2.1   Ways different animals ensure the survival of their species Some animals looks after their eggs and young.  Examples of such animals are:   Different plants have different ways to ensure the survival of their species 1.   Plants have to disperse their seeds far away to avoid competition. 2.   Plants depend on four agents to disperse their seeds.   These agents are :     (a)   Explosive mechanism         Example :                                         Rubber fruit         Balsam fruit         -   When the rubber or balsam fruits mature, they split open and the               seeds are thrown far away. (b)    Wind         Example :                                             Shorea                    Lalang        -   Shorea and lalang seeds are small and light.        -   They also have fine hair and wing-like structures to help them be              blown away. (c)    Water         Example :       -   There are air spaces in the coconut and water lily to help the seeds float in water. (d)   Animals        Example :                                  Love grass                     Papaya         -   The love grass has hooks that can cling on the fur of animals.         -   The papayas are fleshy and brightly coloured fruits which are eaten               by animals. 2.3   The importance of survival of the species If plants become extinct: -   there will be a shortage of food -   other hervivorous species will become extinct, followed by carnivorous species 3.   FOOD CHAINS AND FOOD WEBS 3.1   Food chains 1.   A food chains -   shows how organisms depend on one another for food -   shows the relatioship in one direction only -   always starts with green plants called producers 2.       (a)   The paddy plant is the producer.    (b)   The grasshopper is the primary consumer.    (c)   The frog is the secondary consumer.    (d)   The eagle is the tertiary consumer.    (a)   The plant is the producer.    (b)   The deer is the primary consumer.    (c)   The fox is the secondary consumer.    (d)   The tiger is the tertiary consumer. 3.   Herbivores are animals that eat plants and parts of plants.       Example :             4.   Carnivores are animals which eat other animals.       Example : 5.   Ombivores are animals which eat both plants and other animals.       Example :                   3.2   Food webs 1.   An organism may be a part of more than one food chain. 2.   A change in the population of one species affects the populations of other species. 3.   For example, if the number of rats increases, the number of paddy plants will decrease and the number of grasshoppers, birds and eagles will decrease, because there is no or little food. However, the number of owls will increase and so will the number of snakes because there are more rats to eat. 4.   Some animals eat onlu one type of food.         Example :                                   The panda eats only bamboo shoots.                                The koala eats only eucalyptus leaves.                                                The pangolin eats only ants. 5.   These animals will die out and become extinct when their food source         is not available.
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