Control in Flowering Plants Flashcards
(23 cards)
What are auxins?
They are hormones for cell growth in plants.
What effects do auxins have on shoots?
Cell elongation
What effects do auxins have on roots?
Cell inhibition
How do auxins move within a root or shoot?
Diffusion
Describe uniform light
Uniform - united
Light distributed around the plant evenly
What is geotropism?
–> The growth of plant in response to gravity typically the roots
What is phototropism?
The growth of plant roots and shoots in response to light
What is positive geotropism?
-> When something moves with gravity
-> Roots move with POSITIVE geotropism
What is a tropism
-> A response to a stimulus in the environment from the plant
-> This can either be geotropism or phototropism
What is phototropism
-> a growth response to light
What is POSITIVE phototropism?
–> Positive Phototropism is the growth of the plant towards a light source
–> An example of this is the shoot.
What is NEGATIVE phototropism?
–> The growth of the plant away from a light source
–> An example of this would be the roots of a plant
Example of Natural Asexual Reproduction
- An example of natural asexual reproduction is runners.
what is Asexual Reproduction in Plants
-where the cell divides by mitosis
-genetically identical offspring is produced
Pollination
- The transfer of pollen from the anther to a stigma of a plant
Self Pollination
- when the pollen from a plant is transferred from the anther to the stigma of the same plant
Cross Pollination
- when the pollen from a plant is transferred from the anther to the stigma of a different plant
petals, anther, stigma, stamen, pollen
Insect pollinated plants
- Petals are large and colourful to attract insects
- Anther inside flower
- Stigma Large and Sticky
- stamen inside flower
- Pollen sticky large with hooks
petals, stigma, stamen, anthers, pollen grains
Wind pollinated plants
- Small and dull coloured petals
- Stigma is feathery and outside of flower
- Stamen and anthers are exposed to wind so pollen can be blown away
- Pollen grains are light and smooth so carried by wind more easily
Steps of Fertilisation
- pollen lands on the stigma,
- it grows a pollen tube down through the style to the ovary.
- The nucleus of the pollen grain travels down the pollen tube and fertilises the ovule nucleus
- The fertilised ovule develops into a seed.
- The ovary develops into the fruit.
Factors affecting Germination
- Water - activate digestive enzymes
- Oxygen - for aerobic respiration to release energy
- Suitable temperature for enzymes
Define Germination
- When the shoot and root grow from the seed
glucose on stigma function
- is used for aerobic respiration of pollen tube.
