Sunday, November 15, 2009

Some flower questions?

i have 6 flower questions, need them by monday night. if you can at least answer one of them the help would be appreciated





1) List the specific places in which the egg and sperm nuclei are found.





2) Of what value to the plant are flowers with colorful petals and sweet odors?





3) What are some of the ways in nature in wich pollen is transferred from anther to pistil?





4) The number of stamens in a flower exceeds the number of pistils. Explain the value of this difference.





5) If an unexpected frost kills the blossoms of a peach tree, the tree may bear no fruit this summer. Explain.





6) Fertilization seems to stimulate the changes which take place in ovules and ovaries. Explain what eventually becomes the ovules and the ovary.

Some flower questions?
1. Egg (ovule) nucleus found in embryosac in the ovary.


Sperm (pollen) nucleus will be produced by the generative nucleus which is found within the pollen grain together with the tube nucleus.





2. To attract insect pollinators.





3. By insects (beetles, flies, bees, wasps etc.); by birds;


and by the wind.





4. This increases the chances of at least one pollen grain (made in the anthers) finding its way to the pistil.





5. If the frost kills the blossoms (flowers) of a tree one year there will be no fertilisation of ovules, no embryo plants forming, no seeds forming around them and no fruits developing to disperse the seeds. The fruit is derived from the ovary, and if the ovary is killed (as part of a flower) then the fruit will not develop.





6.The ovule develops into the seed - a tiny embryo plant with a food supply.


The ovary develops into the fruit. The fruit serves to disperse the seeds.


This can be by being sweet and juicy so the seeds get swallowed by animals and carried away to be deposited unharmed in the faeces of that animal; OR...


some fruits have wings, parachutes or blades that help the seed to use wind currents to disperse; OR...


some fruits have hooks like velcro to get snagged in the fur of animals, get carried away til the amimal grooms itself, OR...


finally, some fruits are explosive -as they dry out predetermined lines of stress buildup in the fruit until it pops open, usually with a twist to throw out the seeds.





Hope this helps!
Reply:2. For pollenation. Attractiveness for pollenating bugs like flies, bees, etc


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