Its some research I need to do, Google's not much help.
2006-10-13 05:33:25 · 13 answers · asked by Chaos 2 in Science & Mathematics ➔ Biology
Shoots are positively phototropic i.e. they will grow up towards light while roots are positively geotropic i.e. they will grow downwards, influenced by gravity. (Note: these are tropisms, not trophisms).
If you look at the details in a textbook, you will also find the influence of plant hormones (auxins) and structures within the cells which will give you info about how all this happens.
2006-10-13 08:44:09 · answer #1 · answered by Rozzy 4 · 0⤊ 0⤋
Even I'm confused by some of the answers!
Take a broad bean that has dried (it is the seed of the next generation of broad beans) and put it on either blotting paper or cotton wool that you have moistened. A shoot will appear from the top and a root will appear from the bottom.
Shoots, generally are phototrophic, and will therefore go for the light - upwards. The root is geotrophic, which just means that it will go for the earth - downwards. A root will, have branches or offshoots. The smaller offshoots will actually look for water but the purpose of the main purpose of the root is to get itself embedded into the ground.
By the way, any peas or bean seeds will do well with this experiment - it just depends on how much time you have before you have to send your thesis in.
Look at what you are doing and work a lot of it out for yourself - it really can be quite fascinating!
2006-10-13 13:13:19 · answer #2 · answered by Anonymous · 0⤊ 0⤋
Just need to search for the right words..........
D. Gravitropism
1. An upright plant placed on its side displays negative gravitropism; it grows upward opposite gravity.
2. Charles Darwin and his son were first to show that roots display positive gravitropism.
a. If root cap is removed, roots no longer respond to gravity.
b. Later researchers showed root cap cells contain statoliths, starch grains within amyloplasts.
c. Due to gravity, amyloplasts settle to lowest part of cell.
3. The hormone auxin underlies both positive and negative gravitropisms.
a. The two tissues respond differently to auxin, which moves to lower side of both stems and root.
b. Auxin inhibits growth of root cells; cells of upper surface elongate and root curves downward.
c. Auxin stimulates growth of stem cells; cells of lower surface elongate and stem curves upward.
2006-10-13 12:38:29 · answer #3 · answered by Grant d 4 · 1⤊ 0⤋
the cells in the shoots are phototropic and hence find light while the root cells are programmed to seek water and soil.
2006-10-13 12:43:17 · answer #4 · answered by sumaravindran1958 2 · 0⤊ 0⤋
Shoots grow towards the sunlight. It's called tropism - phototropism and geotropism.
2006-10-13 12:39:06 · answer #5 · answered by True Blue Brit 7 · 0⤊ 0⤋
it is built into their dna and they know what to know= the the roots head for the water and the shoots toward the sun-D
2006-10-13 12:49:21 · answer #6 · answered by Debby B 6 · 0⤊ 0⤋
Shoots are positively phototrophic. Roots are positively geotrophic.
2006-10-13 13:42:05 · answer #7 · answered by BigPak 2 · 0⤊ 0⤋
Roots need water and thus seek water. Shoots need light thus seek light....
2006-10-13 12:41:10 · answer #8 · answered by Dave 2 · 0⤊ 0⤋
Gravity
2006-10-13 12:36:35 · answer #9 · answered by DazerUK 2 · 1⤊ 1⤋
shoots show phtotropism and move towards sunlight opposing the earths gravity
roots show geotropism and hydrotropism. i.e they grow downwards and towards water.
2006-10-13 12:45:20 · answer #10 · answered by medgr8 2 · 0⤊ 0⤋