Plants and Food Flashcards
What is the main storage carbohydrate in plants
Starch
What are the useful products that glucose can be converted to and their uses?
- Starch to use as a storage carbohydrate
- Lipids used as an energy source for seeds.
- Amino Acids to make proteins for growth
What is the equation for Photosynthesis
Carbon Dioxide + Water –> Oxygen + Glucose
What is the purpose of destarching a leaf?
To get rid of the starch that is left on the leaf at the beginning of the experiment.
What is the substance that absorbs carbon dioxide from the environment
Soda Lime
What is starch made out of
Glucose sub-units
How do you show that oxygen is a waste product that is created during photosynthesis.
By submerging an aquatic plant in water and providing a sufficient amount of sunlight.
This will cause bubbles of oxygen gas to be produced underwater.
What are isotopes
These are atoms of the same element with the same number of protons but different number of neutrons, therefore, causing different mass numbers.
What is Photosynthesis
This is the use of simple inorganic molecules like carbon dioxide and water in the presence of chlorophyll and light to produce oxygen and glucose
What is the role of the green pigment Chlorophyll
It is used to absorb light energy that is used for photosynthesis.
What is the energy conversion that happens in photosynthesis
Light Energy —> Chemical Energy
What are the functions of different parts of the leaf structure
Upper Epidermis:
This is the top most layer of the leaf and is transparent to allow light to pass in. It also contains a waxy cuticle to reduce water loss by evaporation.
Lower Epidermis:
These are the cells located at the bottom of the leaf and is where gas exchange takes place. This section of the leaf have pores called, “stomata” that are located between two very specialized cells called, “Guard cells” that increase or decrease the size of the stomata to let gas int and out.
Palisade Layer:
This layer is right below the upper epidermis and contains a large number of thin and long cells called, “palisade cells”. These cells contain hundreds of chloroplasts that are responsible for performing photosynthesis. This is the main site of photosynthesis.
Spongy Mesophyl:
These are the spongy mesophyl cells that are responsible for gas exchange. They also photosynthesis, but not as much as palisade cells.
Xylem:
These carry water and mineral ions throughout the plant that were absorbed by the roots at the bottom. They also supply the spongy mesophyl cells.
Phloem:
These carry the nutrients the plant produces by photosynthesis through the plant to parts of the plant that cannot make their own food.
How is a leaf adapted for photosynthesis
- The leaf has a high surface area to absorb most of the sunlight, which increases the rate of photosynthesis.
- The leaf contains chlorophyll that it uses to absorb sunlight for photosynthesis.
- Contains a large number of palisade cells with a large number of chloroplasts in each cell to perform photosynthesis. This increases the rate of photosynthesis.
- The leaf has stomata to perform gas exchange between oxygen and carbon dioxide.
What is the relationship between photosynthesis and respiration with the light intensity
As the light intensity increases, the photosynthesis rate is higher than the respiration so the plant produces less carbon dioxide.
As the light intensity decreases, the photosynthesis rate is lower than the respiration so the plant produces more Carbon Dioxide
What is the indicator that is used to check for the presence of carbon dioxide
Hydrogen Carbonate
What is the color of Hydrogen Carbonate in different carbon dioxide concentrations
High: Yellow
Normal: Orange
Low: Purple
What are the factors that affect the rate of photosynthesis
- Temperature
- Carbon Dioxide concentration
- Light Intensity
Why does the rate of photosynthesis level off even though the light intensity keeps on increasing
Because there are other factor that also affect photosynthesis. Therefore, even though the light intensity keeps on increasing, those other factors are still lacking. Ex: Carbon Dioxide concentration in the air.
These other factors are called, “limiting factors”
What happens to the rate of photosynthesis as the light intensity increases
As the light intensity increases, the rate of photosynthesis increases but only up to a certain level. Then the rate of photosynthesis levels off because there are other factors that limit the rate of photosynthesis. Ex: Carbon Dioxide concentration, temperature
What happens to the rate of photosynthesis as the carbon dioxide concentration increases
The rate of photosynthesis increases as the carbon dioxide concentration increases. However, only up to a certain level, which then levels off because of other limiting factors.
What happens to the rate of photosynthesis as the temperature increases
The rate of photosynthesis increases as the temperature increases, but only up to a certain level. Because after the temperature goes beyond the optimum temperature, the enzymes start to denature, and the rate decreases.
What are the substances that can be formed by glucose in plants
- Sucrose for transport
- Starch for storage
- Chlorophyll
- Lipid oils in seeds
- Proteins and DNA
- Cellulose for cell walls
What are the uses of different mineral ions in plants?
Nitrates: - Used to make proteins - Used to make DNA - Used to make Chlorophyll etc
Potassium:
- Used to make enzymes needed for respiration and Photosynthesis.
Phosphates:
- Part of the cell membrane
- Used to make DNA and many other compounds.
Magnesium:
- Used to make Chlorophyll
What are the deficiency symptoms for each ion in plants
Nitrates:
- Poor plant growth
- Older leaves turn yellow
Phosphates:
- Poor root growth
- Younger leaves turn purple.
Potassium:
- Leaves turn Yellow and have dead spots
Magnesium:
-Leaves turn yellow.
