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2 nd Year Science Mr Cunningham
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Draw a labelled diagram of the flower Identify the male and female parts of the flower What is the difference between “Asexual” “Sexual” plant reproduction? Name a plant that is produced asexually and describe how it grows in this way? Explain what is meant by a Gamete? Name the 2 gametes in plants and where they are produced.
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The Carpel is the name for all the female parts of the flower. Stigma: The stigma is the place where the pollen grains will land. Style: Connects the Stigma to the Ovary. Ovary: Contains the Ovules. Each ovule produces an egg which is the female gamete.
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The Stamen contains the male parts of the flower. Anther is the head of the stamen and where pollen is produced, pollen is the male gamete The Filament is the tall stalk holding the Anther in place. Pollination is the transfer of pollen from the Stamen of one plant to the carpel of another plant.
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Asexual Reproduction: New plants are formed only from one parent Fertilisation is not part of asexual reproduction. In asexual reproduction the offspring are identical to the parent.
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SexualAsexual Two parentsOne parent Gametes involvedNo gametes involved Offspring is different to the parents. Offspring is identical to the parent.
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Strawberry plants produce special stems called Runners The Runners spread along the ground away from the parent plant The Runners can then develop new roots and a new shoot, forming new strawberry plants Strawberry plants produced from runners have one parent and are identical to the parent.
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A Gamete is the name for a sex cell. In plants like humans there are 2 sex cells The Pollen is the male gamete produced in the Stamen. The egg is the female gamete produced in the ovary (part of the carpel)
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A sex cell is called a Gamete! Sexual reproduction involves 2 Gametes. Fertilisation is the joining of a male gamete and a female gamete. The offspring are not identical to the parents and share characteristics of both parents. This is an advantage to the plants. The flower contains all the parts needed for sexual reproduction.
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Pollination is the transfer of pollen from a stamen to a carpel The pollen produced in the stamen is transferred to the Stigma ( the top of the carpel)
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Wind pollination: The wind carries the pollen from the anther of one plant to the stigma of another plant. Insect Pollination: Insects transfer pollen from the anther of one plant to the stigma of another plant.
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What do you think flowers need to have in order for insects to transfer their pollen to other pants? What do you think flowers need to have in order for their pollen to be transferred by the wind?
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Insect pollination: Colourful petals are attractive to insects which also collect a substance called nectar from the flower. Wind pollination: Do not need to be colourful. Their stamens are loosely attached to the flower and easily blown away by wind.
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The joining of the Male and Female gametes (sex cells) to form a Zygote (single cell) The Zygote will grow to form a seed which becomes the new plant. Take down the diagram of Fertilisation from the board!
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Once the pollen arrives at the stigma, a Pollen Tube grows down to the egg carrying the pollen The egg and pollen can fuse together to form the Zygote
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Once fertilization is complete a Seed forms. A Fruit is formed from the ovary.
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Each seed starts off as a Zygote surrounded by a food supply (the fruit) The Plumule will from the future shoot of the plant The Radicle will form the future roots of the plant What is the fruit formed from??
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After fertilization the ovary becomes the fruit. The fruit contains the seed. The fruit protects the seed before it is dispersed. Common fruits include apples, oranges, pears etc.
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Dispersal is the carrying of the seed as far as possible from the parent plant. Advantage: the young plant does not need to compete with the parent plant for scarce resources such as water and sunlight. The 4 main ways of dispersal are wind, animal, self and water dispersal!
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Involves the fruit bursting open when it is ripe. The seeds are then flung as far way as possible i.e. peas and beans. Water Dispersal :Some fruits or seeds are able to float. This allows them to be carried away by streams, rivers etc.
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Germination is the growth of a seed to form a new plant The conditions necessary for Germination are: 1. Water 2. Oxygen 3. A suitable temperature (warmth)
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The food supply in the seed allows the root and shoot to grow The roots grow down The shoots grow up towards the sunlight Green leaves form and the plant begins to make its own food through Photosynthesis.
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Tube A has 5 cress seeds on wet cotton wool and is in a warm place. This tube is the control can you explain why?? Tube B has 5 cress seeds on dry cotton wool and is in a warm place, what condition is missing? Tube C has 5 cress seeds covered by boiled, cooled water and a layer of oil and is in a warm place, what condition is missing? Why is the water boiled and a layer of oil placed over it?
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Tube D has 5 cress seeds on wet cotton wool and is placed in a cold place, What condition is missing in tube D? What results do we expect? Which test-tubes will have seeds that germinate and why?
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