photosynthesis Flashcards
Ways plants use glucose
nergy source
Glucose can used as a substrate and broken down in plant cells by the process of respiration. The chemical energy released by respiration can be used by the plant for cellular activities such as protein synthesis or cell division.
Plant energy storage
Thousands of glucose molecules can be linked together to form the complex carbohydrate starch. Starch is stored inside plant cells as grains. Insoluble doesn’t draw water in from osmosis
Plant building material
Thousands of glucose molecules can be linked together to form the complex carbohydrate cellulose. Cellulose is a very tough molecule that is used to build the cell wall of plant cells.
Production of other types of food
Glucose is an example of a carbohydrate - it contains the chemical elements carbon, hydrogen and oxygen. Plant cells can convert the sugar into another type of energy storage molecule - fat.
Plant cells can also combine sugars with nitrates to make amino acids and use these to produce proteins.
What kind of reaction is photosynthesis
endothermic as energy transferred to chloroplasts from the environment the light
How does temperature affect photosynthesis
If temp gets to hot enzymes needed for photosynthesis and other reactions damaged
But goes up until 45 due to enzymes work better / quicker and molecules (substrates move faster)
How are light intensity and distance related
he inverse square law shows the relationship between light intensity and distance.
As the distance increases the light intensity decreases. This means that they are inversely proportional to each other
Light intensity and distance are inversely proportional to each other
This means that as the distance doubles you decrease the intensity of the light will be four times less
This is called the inverse square law and shown by the equation below:
light intensity = 1/d squared
How are farmers controlling control factors of photosynthesis good
Limiting factors are important in the economics of enhancing the conditions in greenhouses to gain the maximum rate of photosynthesis while still maintaining profit
Keeping plants in a greenhouse has associated costs, but the increased yield of the crop and fact that the crop can be harvested more frequently, means that the farmer will make more money
The levels of heat, light, water, carbon dioxide and nutrients are carefully controlled so only the smallest amounts needed are used so that farmers are not wasting money
What kind of things can farmers add
use greenhouses constructed from glass or alternative materials that enable maximum transmission of light
position plants for maximum light absorption
Artificial lighting systems can be used:
with increased light intensities
that provide optimum wavelengths of light for photosynthesis
that lengthen a plant’s growing season so that crops can be grown in more months of the year
use paraffin heaters on a small scale
on a larger scale, use carbon dioxide wastes from industrial processes that has been cleaned up before use
can use liquid carbon dioxide, applied through pipes, though this can be expensive
Irrigation systems are also used outdoors.
Heat is often used in greenhouses and makes plant growth possible when the weather is cold outside.
Increased temperatures in greenhouses increase the rate of photosynthesis. Temperature regulation is important – note that cooling may also be required
