How do you measure the rate of photosynthesis?

How do you measure the rate of photosynthesis?

The rate of photosynthesis will be measured by counting the number of oxygen bubbles produced by the Elodea plants in each 2-minute trail. After completing a number of experiments, students and teachers will discuss their findings in relation to macro-level factors that affect ecosystem health and climate change.

What is the variable in the photosynthesis in leaf disks experiment?

For example the one independent variable is the “light intensity” and the dependent is the “rate of photosynthesis” in leaf discs.

Why is ET50 used to determine the rate of photosynthesis?

The ET50 is the time it takes for 50% of the leaf disks to float and is a good indicator of the rate of photosynthesis. It was hypothesized that if the concentration of carbon dioxide was increased, then the rate at which photosynthesis occurs will also increase.

What is the leaf disc experiment?

When you apply a gentle vacuum to the leaf disks in solution, this air is forced out and replaced with solution, causing the leaves to sink. When you see tiny bubbles forming on the leaf disks during this experiment, you’re actually observing the net production of O2 gas as a byproduct of photosynthesis.

Why do we calculate the rate of photosynthesis?

Light intensity Light provides the energy needed for photosynthesis. Increasing the light intensity increases the rate of photosynthesis, provided plenty of carbon dioxide and water are available. The maximum rate is determined by the other factors involved.

What three factors affect the rate of photosynthesis?

Three factors can limit the rate of photosynthesis: light intensity, carbon dioxide concentration and temperature.

• Light intensity. Without enough light, a plant cannot photosynthesise very quickly – even if there is plenty of water and carbon dioxide.
• Carbon dioxide concentration.
• Temperature.

What are the 4 factors that affect photosynthesis?

Photosynthesis is affected by light, temperature, water, and CO2. Stomata affect the process of transpiration and do not affect photosynthesis.

Why did the leaf disks begin to float?

Leaf disks float, normally. When the air spaces are replaced with water the overall density of the leaf disk increases and the disk sinks. As photosynthesis proceeds oxygen is released into the interior of the leaf which changes the buoyancy–causing the disks to rise.

Which wavelengths of light are the most effective in photosynthesis?

The best wavelengths of visible light for photosynthesis fall within the blue range (425–450 nm) and red range (600–700 nm). Therefore, the best light sources for photosynthesis should ideally emit light in the blue and red ranges.

Which light is best for promoting photosynthesis in spinach?

White light
Light is essential in photosynthesis and different colored lights were tested on spinach leaf cells. White light appears to be the most effective light for photosynthesis, but apart from white, red light is also effective.

What gives the leaf disks their buoyancy?

As photosynthesis proceeds, oxygen accumulates in the air spaces of the spongy mesophyll. The leaf becomes buoyant and floats. While this is going on, the leaf is also carrying out cellular respiration. This respiration will consume the oxygen that has accumulated and possibly cause the plant disks to sink.

How do you calculate the rate of photosynthesis and volume change?

Subtract the original volume at 0 min from the final reading at 120 min to determine the volume change. Divide the change in volume by the time, 120 min, to obtain the rate of O2 production in units of mL/min.