Conditions needed for photosynthesis

Photosynthesis needs:

• chlorophyll

• carbon dioxide (from the air)

• water (from the soil)

• sunlight energy (any light will do except green light)

Photosynthesis produces:

• glucose

• oxygen (a waste product)

Chlorophyll and light energy both need to be present for photosynthesis to take place, but they are not actually part of the reaction – they are not used up. So in the word equation for photosynthesis, remember to write them above the arrow, like this:

A general equation for photosynthesis is:

6H₂O + 6CO₂ -------- C₆H₁₂O₆+ 6O₂

Most of us don’t speak chemicalese, so the above chemical equation translates as: six molecules of water plus six molecules of carbon dioxide produce one molecule of sugar plus six molecules of oxygen. You need to understand how the carbon dioxide and water molecules are broken down and reassembled to form the glucose molecules. Like all chemical equations the photosynthesis equation is balanced – that is, there are the same number of carbon, hydrogen and oxygen atoms on either side of the equation.

10. Translate from Russian into English:

Пищевые цепи, солнечный свет, производство пищи, химическая реакция, листья растений, зелёный пигмент хлорофилл, превращаться в крахмал, побочный продукт, особые клетки, путём построения, по направлению к, известны как продуценты.

11. Match the following expressions with prepositions with their English equivalents:

внутри зелёных листьев растения	at the beginning
в течение этой реакции	known as ‘producers’
превращать в	by building up
путём построения	towards
также	as well
по направлению к	during this reaction
известны как продуценты	inside a green plant’s leaves.
в начале	convert into

12. Put the words in the correct order to make sentences in the Present Simple Active or in the Present Simple Passive:

a) day / Kate / up / at / seven / and / o` clock / has / goes / takes / every / a / wakes / shower / breakfast / after / that / to / the / university

b) Kate’s / group / usually / hours / of / botany / three / has / times / a / three / week

c) simple / carbohydrates / inorganic / up / from / green / are / chemicals / in / proteins / and / fats / plants / built

d) food / plants / produce / need / green / sunlight / to

e) into / glucose / starch / used / respiration / is / converted / in / and / stored / or

f) are / reaction / glucose / carbon / this / water / during / and / converted / into / and / oxygen / dioxide

g) sunlight / this / form / in / requires / reaction / the / energy / of

h) takes / the / mesophyll / in / photosynthesis / plant’s / cells / inside / place / green / a / leaves /

i) bodies / called / the / called / tiny / mesophyll / cells / contain / chemical / which / chloroplasts / contain / a / green / chlorophyll

j) dioxide / photosynthesis / chlorophyll / needs / water / sunlight / carbon / energy

k) photosynthesis / glucose / oxygen / produces