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B1 Plants Hormone
Edexcel B1 Plant hormones
Question | Answer |
---|---|
what is tropism | When a living thing grows towards or away from a stimulus |
What is a negative tropism? | When a living thing grows away from a stimulus |
What is the nae of the tropism caused by light? | Phototropism |
What is the name of the tropism caused by the pull of gravity? | Gravitropism aka geotropism |
What is the name of teh hormoneresponsible for plants growing towards the light? | Auxin |
What is the name of the hormoneresponsible for a root growing down? | Auxin |
What is the hormoneresponsible for the starch (stored in the seed) to turn into sugar? | Gibberelin |
Explain why shoots grow towards the light | 1)Auxin are made in the tip of the shoot 2) Auxin moves down and away from the light 3) the cells on the side of the shoot with the auxin will grow longer |
What is the name of the process by which cells grow longer? | Elongate |
Why is this useful for plants to grow towards the light? | More sunlight=more photosynthesis=more growthWhat is the effect of Auxin in roots?Auxin stop root cells elongating |
What experiment could you do to show that Auxins move down the shoot? | Cut the tip of the shoot and place a bit of plastic between the two bits: the plant will NOT grow towards the light |
What experiment could you do to show that Auxin are found in teh shaded side? | Make a small cut on the shaded side and insert a piece of plastic: the shoot does NOT grow towards the light |
What experiment could you do to show that the Auxin is producedin the tip of the shoot? | Cut the tip of the shoot; the shoot will NOT grow towards the lightWhat is the stimulus that releases gibberelins? |
Why do seeds soaked in gibberelins germinates before seeds soaked in water? | Gibberelins will turn the stored starch into sugar; they provide the seed with energy |
What hormone is used as a weedkiller? | Auxin |
What is a selective weedkiller? | A weedkiller that kills only certain plants/ plants with broad leaves |
What hormoneis used to help grow roots on cuttings? | Auxin |
What hormone is used to grow bigger fruits on seedless varieties? | Gibberelins |
What gas helps fruit ripen? | Ethene |
Why would is be useful for fruits on a tree to fall ALL at the SAME time? | This stops some fruits falling on the ground and getting damaged; it also helps pick all the fruits in one go |
Why would it be useful to artificially ripen fruits (ie pick green bananas and ship them to the UK)? | So that the consumers ALWAYS get ripe fruits when he/she buys them |