Question

1. Write down your "if.....then ...... because" hypothesis for the transpiration condition you plan to test in Procedure 1, and have it initialed by your TA. • Follow the "if (insert independent variable (what you are changing))..., then (insert dependent variable (what you expect to see/measure)..., because... format. Keep it simple and concise, not too broad. Avoid using words like I think, believe, all, never, and sometimes. These words may either personalize it or are too vague and will result in too broad of an area to research. Avoid using words such as "prove" and "significant" in a hypothesis. 2. Climate change due to the rapidly increasing levels of greenhouse gases (particularly CO2) in our atmosphere is a serious current global concern. How might stomata density serve as a bio- indicator for monitoring the response of plants to changes in greenhouse gas concentrations in the future (If the plants are responding to the CO2 levels)?

Answer 1

Stomata are tiny pores on leaves which allow exchange of gases like co2 and o2. About 99 percent water absorbed by roots is lost through stomata ..

Stomata are present on upper epidermis and lower epidermis.

About 0 to 58000 per square cm stomata are present on leaves . More on lower epidermis than upper epidermis.

Stomata density decreases in high co2, concentration.

Stomatal index is used for stomata density.

I= S/E+S ×100 where I is stomata index

S is stomata per unit area

E is epidermal cells per unit area.

If co2, concentration increases in atmosphere , plants closes their stomata as they do not need more co2 to enter. for photosynthesis. Hence stomata decreases on high co2, concentration.

If co2, and green house emission is decreased plants open their stomata to allow more co2 to enter for photosynthesis.