The main variables which affect photosynthesis are light, water, CO2 concentration and temperature.
On a deeper level, other factors like amount of chlorophyll, availability of nutrients (eg Mg is needed for chlorophyll synthesis) will also affect the rate of photosynthesis, though these are rarely covered in discussion of this topic.
The thing is that photosynthesis will be held back by whichever factor is in shortest supply.
As I sit in my study in England, the sun is shining brightly, but the temperature outside is only 5ºC. I suspect the rate of photosynthesis is limited by temperature today.
Yesterday was a dull day, but in the middle of the day it was not cold and I suspect there wasn't enough light for photosynthesis. If I had turned the security lights on my house on, the plants in my garden might (possibly) have photosynthesised faster.
In summer, some farmers growing crops in glasshouses actually increase the amount of carbon dioxide in the air as all their plants have plenty of water and light and the temperature is near the best possible for photosynthesis.
A good way to investigate this might be with the help of algae and you can use the 'Immobilised Algae' practical for this.
Although water is needed as a raw material for photosynthesis, don't bother trying to investigate water as a variable - plants normally wilt and wither long before water restricts photosynthesis at the biochemical level. They need water to support the plant to face the sun as well as a raw material of photosynthesis.
The simplest equation for photosynthesis:-
Carbon dioxide + water -----(in light, with chlorophyll and enzymes)----> sugar + oxygen
Temperature speeds up all chemical reactions - photosynthesis is no exception.
Enzymes work better in warm conditions (up to about 50ºC when enzymes start to be destroyed by heat).
The idea to get across is that different conditions will be most important on different occasions. This morning, my garden could do with more warmth - yesterday, it could do with more light / sun!
25% will be expected to have the TTYy combination.
Hope this helps!
I think they are the constituents of granite. Granite is a common type of felsic intrusive igneous rock that is granular and phaneritic in texture. It is the most widespread of igneous rocks, underlying much of the continental crust. It is mined as either crushed stone or dimension stone mainly using open pit mining methods.
Answer:
Radiolabeled carbon atom in CO2
Explanation:
Photosynthesis is the process by which green plants fix the atmospheric CO2 into glucose. The process includes carbon fixation during which RuBisCo enzyme catalyzes the reaction of CO2 and a five-carbon compound called RuBP to form 3-phosphoglycerate (3-PGA). The 3-PGA enters the reduction phase of the Calvin cycle wherein it is reduced into glyceraldehyde 3-phosphate. Two molecules of glyceraldehyde 3-phosphate make one molecule of glucose.
To test the hypothesis that glyceraldehyde 3-phosphate from photosynthesis is used by plants to synthesize lipids, radiolabeled CO2 must be used. The radiolabeled carbon atom in the CO2 would be fixed in the form of glyceraldehyde 3-phosphate. If the plant uses glyceraldehyde 3-phosphate as a precursor for lipid synthesis, the synthesized lipid molecules would carry the radiolabeled carbon atom.
Answer:
B. So you can always see the entire object at the higher magnification
Explanation:
A microscope is used to view objects smaller than the naked or unaided eyes can see. The objective lens, in conjunction with the occular or eye lens, is used to achieve this purpose. The objective lens are of different magnifications as follows: 10X, 40X, 100X etc.
However, as the magnification increases i.e. higher objective, the object in the field of view becomes smaller and less focused. Hence, the object in the field of view must first be centered at a lower magnification/objective lens before changing to a higher one in order for the entire object to be seen at a higher magnification.
