G8 photosynthesis and the carbon cycle REVIEW

Which gas is used in photosynthesis?

(a)  

Answer explanation

In photosynthesis, plants use carbon dioxide (CO2) as the primary gas. During this process, plants absorb carbon dioxide from the atmosphere through small openings in their leaves called stomata. Inside the plant cells, carbon dioxide is combined with water (H2O) using energy from sunlight to produce glucose (a type of sugar) and oxygen (O2). This process takes place in the chloroplasts, which contain a green pigment called chlorophyll that captures the sunlight. The oxygen produced is released back into the atmosphere as a byproduct. Thus, carbon dioxide is the essential gas used in photosynthesis. 在光合作用过程中，植物主要使用二氧化碳（CO2）这种气体。植物通过叶子上的小孔（称为气孔）从大气中吸收二氧化碳。在叶绿体内，二氧化碳与水结合，在光的作用下，通过化学反应生成葡萄糖和氧气。

Which gas is made by plants in photosynthesis?

(a)  

Answer explanation

During photosynthesis, plants convert carbon dioxide and water into glucose and oxygen. The gas produced and released by plants is oxygen, which is essential for most living organisms.

Where do plants get their water for photosynthesis?

(a)  

Answer explanation

Plants primarily obtain water for photosynthesis from the soil through their roots. This water is essential for the photosynthesis process, where it combines with carbon dioxide to produce glucose and oxygen.

what is the green pigment that plants use to absorb light energy?

(a)  

Answer explanation

The green pigment that plants use to absorb light energy is chlorophyll. It plays a crucial role in photosynthesis by capturing sunlight, which is essential for converting carbon dioxide and water into glucose.

What are the tiny holes in a leaf that allow gases to diffuse in and out?

(a)  

Answer explanation

The tiny holes in a leaf that allow gases to diffuse in and out are called stomata. Each individual hole is referred to as a stoma, but the correct term for the collective is stomata.

Sara wants to find out out of 2 types of seaweed, which seaweed has a higher photosynthesis rate. Which variable should she change in her experiment?

(a)  

Answer explanation

Sara should change the type of seaweed in her experiment. By comparing different types, she can determine which one has a higher photosynthesis rate, making it the independent variable in her study.

Sara wants to find out out of 2 types of seaweed, which seaweed has a higher photosynthesis rate. Write down 3 variables she should keep the same.

(a)  

Answer explanation

To accurately compare photosynthesis rates, Sara should keep the same light intensity, same temperature, and same CO2 levels. These factors directly influence photosynthesis, ensuring a fair comparison between the two seaweed types.

Sara wants to find out out of 2 types of seaweed, which seaweed has a higher photosynthesis rate. What should Sara measure in her experiment?

(a)  

Answer explanation

To determine which seaweed has a higher photosynthesis rate, Sara should measure the amount of oxygen made by the plants. This directly reflects the rate of photosynthesis, as oxygen is a byproduct of this process.

what is A

(a)  

what is B

(a)