ГДЗ по английскому языку 10 класс упражнение - 3 р. 76

1. a) Read the texts and match the paragraphs (A-G) with the headings (1-8). Put your answers into the table. Each number can only be used once. There is one extra heading. Then, listen and check.  

 

1. The raw materials   
2. Now for the technical bit!   
3. The circle of life     
4. Making life possible    
5. In the dark        
6. A threat to the process      
7. Changing the form of energy       
8. A long history    

 

A	B	C	D	E	F	G

 

Photosynthesis  

 

1. Energy moves along the food chain from one life form to another. Some animals eat plants to get energy. Other animals then eat these animals. Plants form the foundation of the food chain by producing their own food using energy from the sun, through a process called photosynthesis.  

 

1. Photosynthesis is very ancient. Before there were plants, tiny creatures called bacteria carried out photosynthesis. In fact, this was happening more than 3 billion years ago. That is a long time!   

 

1. Photosynthesis uses energy from the sun to change carbon dioxide (CO2) and water (H2O) into carbohydrates and oxygen gas. Carbohydrates are chemicals that contain hydrogen, carbon and oxygen. The chemical reaction can be summarised by this equation.  

 

    

 

1. To start the process, the plant absorbs carbon dioxide through tiny holes in its leaves and sucks up water from the soil through its roots. A green substance in the plant’s leaves called chlorophyll absorbs energy from the sun. The plant now has all it needs for photosynthesis to begin.    

    

1. There are two stages to the photosynthesis process. In the first stage, called the light reaction, light energy from the sun is converted into chemical energy. This energy is stored in a chemical called ATP (adenosine triphosphate).  

 

1. The second stage does not require sunlight to take place. This part of the process is called the “darkreaction”. In this stage the plant uses ATP to convert the carbon dioxide and water into carbohydrates. Carbohydrates provide the plant with the energy it needs in order to grow.    

 

1. Clearly, photosynthesis is very important for every living thing. As well as providing food for the plant from the sun’s energy, it indirectly provides food for every other living creature. Not only that, it also produces the oxygen that animals need to breathe. Without photosynthesis, our planet could not support life as we know it.     

 

1. b) Explain the words in bold.