Photosynthesis and Chlorophyll
Background:
A pigment is a substance that absorbs light of particular wavelengths. Plants contain multiple types of pigment such as chlorophyll and carotenoids. If you see a leaf that is green or green-yellow in color, that is due to a pigment in the leaf called chlorophyll. Sunlight, which is categorized as "white" light, contains all of the colors of the spectrum. When it shines on the plant leaf, the chlorophyll absorbs some wavelengths and reflects other wavelengths. That is why you see specific colors. There are two different forms of chlorophyll (chlorophyll a and chlorophyll b), and they each absorb and reflect different ranges of wavelengths.
A spectrophotometer is an instrument that can be used to measure the amount of light absorbed by a pigment. The graph below shows the percent of light energy absorbed for the different light wavelengths. The highest peaks represent the colors that the chlorophyll absorbs the most, and therefore, they are seen the least.
blue green yellow orange red
Question 1
8. According to the graph above, which chlorophyll is going to appear greener to our eyes? (Hint: Look at the line for chlorophyll a and the line for chlorophyll b. Which one has a "valley" that shows better reflection for a wider range of green light?)(1 point)
Responses
chlorophyll a
chlorophyll a
chlorophyll b
chlorophyll b
Question 2
9. According to the graph above, which chlorophyll has greater absorbance of the dark orange (or orange-red) light wavelength? (Hint: Look at the line for chlorophyll a and the line for chlorophyll b. Which one has a higher peak in the dark orange or orange-red range?)(1 point)
Responses
chlorophyll a
chlorophyll a
chlorophyll b
chlorophyll b
Question 3
10. According to the graph above, which of the colors absorbed by chlorophyll b has the greatest absorbance? (Hint: Look at the red line for chlorophyll b. Find the color associated with its highest peak.)(1 point)
Responses
green
green
yellow
yellow
red
red
blue
19 answers
According to the graph above, chlorophyll a is going to appear greener to our eyes.
Question 2:
According to the graph above, chlorophyll b has greater absorbance of the dark orange (or orange-red) light wavelength.
Question 3:
According to the graph above, the color absorbed by chlorophyll b with the greatest absorbance is blue.
(1 point)
Responses
oxygen gas
oxygen gas
carbon dioxide gas
carbon dioxide gas
hydrogen gas
hydrogen gas
glucose sugar
glucose sugar
Question 2
11b. After a while, you notice the bubbles are no longer forming. You ask your teacher how to make the plant start producing bubbles again, and she tells you to blow through the straw into the water. Why did she suggest that?(1 point)
Responses
Blowing through the straw removes oxygen from the water.
Blowing through the straw removes oxygen from the water.
Blowing through the straw removes glucose from the water.
Blowing through the straw removes glucose from the water.
Blowing through the straw adds more carbon dioxide to the water.
Blowing through the straw adds more carbon dioxide to the water.
Blowing through the straw adds glucose to the water.
Blowing through the straw adds glucose to the water.
Blowing through the straw removes carbon dioxide from the water.
Blowing through the straw removes carbon dioxide from the water.
Question 3
11c. What process have you been observing?(1 point)
Responses
decomposition
decomposition
sedimentation
sedimentation
cellular respiration
cellular respiration
photosynthesis
oxygen gas
Blowing through the straw adds more carbon dioxide to the water.
photosynthesis
(2 points)
Drop target 1
Drop target 2
Drop target 3
Drop target 4
Drop target 5
Drop target 6
26121418
Question 2
12b. Drag and drop the numbers into the table to show how many atoms of each type are represented on each side of the cellular respiration reaction.(2 points)
Drop target 1
Drop target 2
Drop target 3
Drop target 4
Drop target 5
Drop target 6
26121418
(2 points)
producer primary consumer secondary consumer tertiary consumer
rabbit
producer – rabbit
primary consumer – rabbit
secondary consumer – rabbit
tertiary consumer – rabbit
grasses
producer – grasses
primary consumer – grasses
secondary consumer – grasses
tertiary consumer – grasses
frog
producer – frog
primary consumer – frog
secondary consumer – frog
tertiary consumer – frog
snake
producer – snake
primary consumer – snake
secondary consumer – snake
tertiary consumer – snake
Question 2
14. Why is there a limit to the number of levels that can exist in a food web or energy pyramid?(1 point)
Responses
The amount of energy available for use by the next organisms decreases going up from one level to the next.
The amount of energy available for use by the next organisms decreases going up from one level to the next.
The amount of energy available for use by the next organisms increases going up from one level to the next.
The amount of energy available for use by the next organisms increases going up from one level to the next.
The amount of energy available for use by the next organisms decreases going down from one level to the next.
The amount of energy available for use by the next organisms decreases going down from one level to the next.
Question 3
15. Which organisms are considered autotrophs?(1 point)
Responses
grasses
grasses
hawks
hawks
frogs
frogs
rabbits
rabbits
Question 4
Food webs and energy pyramids show the movement of matter and energy through ecosystems.
16. Click to show how matter and energy move through ecosystems.
(2 points)
matter energy
flows through the ecosystem
matter – flows through the ecosystem
energy – flows through the ecosystem
cycles within the ecosystem
matter – cycles within the ecosystem
energy – cycles within the ecosystem
Earth has a generally fixed amount
matter – Earth has a generally fixed amount
energy – Earth has a generally fixed amount
Earth is always receiving more
matter – Earth is always receiving more
energy – Earth is always receiving more
- grasses
primary consumer
- rabbit
secondary consumer
- frog
tertiary consumer
- snake
14. The correct response is:
The amount of energy available for use by the next organisms decreases going up from one level to the next.
15. The autotrophs in the given options are:
- grasses
16. matter: cycles within the ecosystem
energy: flows through the ecosystem
matter energy
flows through the ecosystem
matter – flows through the ecosystem
energy – flows through the ecosystem
cycles within the ecosystem
matter – cycles within the ecosystem
energy – cycles within the ecosystem
Earth has a generally fixed amount
matter – Earth has a generally fixed amount
energy – Earth has a generally fixed amount
Earth is always receiving more
matter – Earth is always receiving more
energy – Earth is always receiving more
energy - flows through the ecosystem
flows through the ecosystem
matter – flows through the ecosystem
energy – flows through the ecosystem
cycles within the ecosystem
matter – cycles within the ecosystem
energy – cycles within the ecosystem
Earth has a generally fixed amount
matter – Earth has a generally fixed amount
energy – Earth has a generally fixed amount
Earth is always receiving more
matter – Earth is always receiving more
energy – Earth is always receiving more
energy - flows through the ecosystem
- Rabbit: primary consumer
- Grasses: producer
- Frog: secondary consumer
- Snake: tertiary consumer
14. The limit to the number of levels in a food web or energy pyramid is due to the decrease in energy available for use by the next organisms as you move up from one level to the next.
15. Autotrophs are organisms that can produce their own food. In this case, the autotroph is grasses.
16. Matter cycles within the ecosystem, while energy flows through the ecosystem. Earth has a generally fixed amount of matter and energy.
cycles within the ecosystem matter or energy
Earth has a generally fixed amount matter or energy
Earth is always receiving more matter or energy
cycles within the ecosystem: matter
Earth has a generally fixed amount: matter and energy
Earth is always receiving more: energy
photosynthesis cellular respiration
involves at least one chemical reaction
photosynthesis – involves at least one chemical reaction
cellular respiration – involves at least one chemical reaction
rearranges carbon, hydrogen, and oxygen atoms
photosynthesis – rearranges carbon, hydrogen, and oxygen atoms
cellular respiration – rearranges carbon, hydrogen, and oxygen atoms
occurs in cells in green plants
photosynthesis – occurs in cells in green plants
cellular respiration – occurs in cells in green plants
occurs in cells in animals
photosynthesis – occurs in cells in animals
cellular respiration – occurs in cells in animals
produces glucose that can be stored for later use
photosynthesis – produces glucose that can be stored for later use
cellular respiration – produces glucose that can be stored for later use
uses glucose as a source of energy
photosynthesis – uses glucose as a source of energy
cellular respiration – uses glucose as a source of energy
- involves at least one chemical reaction
- rearranges carbon, hydrogen, and oxygen atoms
- occurs in cells in green plants
- produces glucose that can be stored for later use
- uses glucose as a source of energy
cellular respiration:
- involves at least one chemical reaction
- rearranges carbon, hydrogen, and oxygen atoms
- occurs in cells in green plants
- occurs in cells in animals
- produces glucose that can be stored for later use
- uses glucose as a source of energy