Chapter 7

Questions:

Why is photosynthesis so important ?

Photosynthesis creates oxygen out of CO2. That is very important especially for living organisms that need oxygen to be able to breathe.

What does photosynthesis use to make energy ?

At first the plant absorbs light and uses H2O to produce O2. During this time photosynthesis also creates NADPH and ATP so the plant can use it in second process to create sugar out of CO2

What happens during Calvin cycle ?

Calvin cycle occurs in the stroma of the chloroplast. It is a serie of r

eactions that assembles sugar molecules using CO2 and the energy containing products of the light reactions. this stage is named after Melvin Calvin. During this stage happens the most important process the change from inorganic material into organic material.

Diagram :

This diagram shows overall process of photosynthesis. It also shows the flow of ATP and NADPH between the Photosystem I and II and Calvin cycle , which is very important for the phases of photosynthesis.

5facts:

Light reactions include the steps that convert light energy into chemical energy.

Chlorophyll a is light-absorbing pigment in the chloroplast. Chlorophyll plays main role during photosynthesis.

Plants produces O2 as a secondary product of photosynthesis.

Some plants such as C4 and CAM plants are able to save water better than C3 plants, because they first fixate CO2 into a four-carbon compound not three-carbon compound (Calvin cycle).

Photosynthesis can be divided into 2 phases. 1 is when the plant needs light and the 2 is when plant can sustain the process of photosynthesis without light.

Key terms :

Mesophyll - green tissue in the interior of the leaf

Thylakoids - interconnected membranous sacs

Stroma - thick fluid filling up chloroplast

Chlorophyll - light-absorbing pigment

Photoautotrophs - organisms that are able to produce organic molecules from inorganic molecule using the energy of light

Photon - fixed quantity of light energy

Wavelength - distance between the crests of two adjacent waves

Photosystem - consists of a number of light-harvesting complexes

C3 plants - called because the first organic compound produced is three-carbon compound 3-PGA

Global warning - slow but steady rise in the Earth's temperature

Video :

Photosynthesis

Summarize :

This chapter explained the process of photosynthesis. The way plants can transform inorganic molecules into organic molecules. It described the way the light is accepted by chlorophyll and how the process continues inside Photosystems I and II and how it finishes up in Calvin cycle