What is photosynthesis? Photosynthesis is a food-making process that occurs in green plants. It is the chief function of leaves. The word photosynthesis means putting together with light. Green plants use energy from light to combine carbon dioxide and water to make sugar and other chemical compounds.
How is the light used in photosynthesis?
The light used in photosynthesis is absorbed by a green pigment called chlorophyll. Each food-making cell in a plant leaf contains chlorophyll in small bodies called chloroplasts. In chloroplast, light energy causes water drawn form the soil to split into hydrogen and oxygen.
What are the steps of photosynthesis process? Let me tell you the process of photosynthesis, in a series of complicated steps, the hydrogen combines with carbon dioxide from the air, forming a simple sugar. Oxygen from the water molecules is given off in the process. From sugar together with nitrogen, sulphur, and phosporus from the soil-green plants can make starch, fat, protein, vitamins, and other complex compounds essential for life. Photosynthesis provides the chemical energy that is needed to produced these compounds.
1. What step after the hydrogen combines with carbon dioxide from the air …
A. Photosynthesis provides the chemical energy that is needed to produced these compounds.
B. Water drawn form the soil to split into hydrogen and oxygen.
C. Food-making process that occurs in green plants.
D. Phosporus from the soil-green plants can make starch, fat, protein, vitamins, and other complex compounds essential for life.
E. Oxygen from the water molecules is given off in the process.
ANS : E
2. What are photosynthesis need …
A. Water, light, oxygen, worm
B. Soil, chlorophyll, sun, human
C. Bug, air, oxigen, food
D. Light, Carbon dioxide, humus
E. Candle, vitamins, hydrogen
ANS : D
3. What kind of the text …
A. Narrative text
B. Hortatory text
C. Descussion text
D. Explanation text
E. Descriptive text
ANS : D
Biodiesel is a clean burning substitute for petroleum based diesel fuel. Biodiesel is made of vegetable oil.
To make or manufacture Biodiesel, you must first start with raw materials. The raw materials needed in the production of Biodiesel are a small amount of methanol and a ready supply of vegetable product. One of the most common vegetables used in the production of Biodiesel is corn, although depending on the geographic location of the manufacturing facility many other plants are used as well (rapeseed, soybeans, flaxseed, etc.). The first step is to use the raw vegetable product to make vegetable oil. Vegetable oil by itself will not be what you need to power a car, from here it has to be processed into Biodiesel.
The process for converting vegetable oil into Biodiesel is sometimes called ester interchange. To complete this process the vegetable oil has to be combined with a smaller amount of methanol and then put in the presence of a small quantity of an alkaline catalyst (for example, 5% to 1% sodium hydroxide). Vegetable oil is made up of so-called triglycerides, which is a compound of the trivalent alcohol glycerin with three fatty acids. The goal of ester interchange is to separate the glycerin molecule from the three fatty acids and replace it with three methanol molecules. This process then yields roughly 90% Biodiesel and 10% of a glycerin byproduct. The glycerin byproduct can be used in a number of other chemical processes for different industries.
4. According to the text, one of the advantages in using biodiesel is…
A. it is cheap.
B. it only uses vegetable oil.
C. it uses replaceable materials.
D. it can be done in small industry.
E. it gives less pollution than petroleum
ANS: E
5. “The process for converting vegetable oil…”(Paragraph 3). The word “converting” is closest in meaning to…
A. Producing
B. Separating
C. Attaching
D. Processing
E. Changing
ANS : E
