Photosynthesis IB Biology

Absorption spectra of two photosynthetic pigments are shown. Phycoerythrin is a red pigment found in many marine red algae, while chlorophyll a is the major pigment in green plants and algae. What do the absorption spectra show about the pigments?

• A.  Phycoerythrin absorbs mostly red light.

• B.  Chlorophyll a reflects more green light than phycoerythrin.

• C.  Chlorophyll a photosynthesizes more at 550 nm than phycoerythrin.

• D.  Phycoerythrin does not absorb blue light.

Tags

NGSS.HS-LS1-5

The action spectra for two different types of photosynthetic organisms are shown. Ulva, or sea lettuce, is a green marine alga composed of two layers of cells. The action spectrum for crop plants was plotted from an average of 22 species of plants. What describes photosynthesis in these organisms?

• A.  Ulva photosynthesizes more than crop plants at red wavelengths.

• B.  Crop plants photosynthesize more than Ulva in green light.

• C.  Photosynthesis by Ulva is highest in red light while that of crop plants is highest in blue.

• D.  Both have zero photosynthesis at 750 nm.

Tags

NGSS.HS-LS1-5

The graph shows how the rate of photosynthesis of a green plant varies with CO₂ concentration at two different light intensities. The temperature is kept constant at 20 °C. What is the limiting factor at X?

• A. Chlorophyll

• B. Light intensity

• C. Temperature

• D. CO₂ concentration

Tags

NGSS.HS-LS1-5

The apparatus shown was used to investigate the effect of varying carbon dioxide concentration on the rate of photosynthesis. Carbon dioxide concentrations were varied by adding different amounts of sodium hydrogen carbonate (NaHCO₃) to water. What is the dependent variable in this investigation?

• A. Temperature

• B. Light intensity

• C. Amount of NaHCO₃ added

• D. Volume of oxygen produced

Tags

NGSS.HS-LS2-5

What does an action spectrum for photosynthesis show?

• A. The range of conditions over which photosynthesis can occur in a plant

• B. The percentage of light absorbed at each wavelength by photosynthetic pigments

• C. The percentage of light absorbed at each energy level by a plant

• D. The relative amount of photosynthesis at each wavelength of light

What prevents plants from converting carbon dioxide into glucose in the dark?

• A. They do not have a source of energy.

• B. It is too cold.

• C. They do not require glucose during the night.

• D. Their enzymes are inhibited.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

In 1882, Engelmann investigated photosynthesis by shining light of varying wavelength on a green alga. He observed where aerobic bacteria accumulated. What can be deduced from this experiment?

• A. Only parts of the chloroplast contained chlorophyll.

• B. The distribution of bacteria indicates the action spectrum of photosynthesis.

• C. Most oxygen is released from the algae in green light.

• D. Chloroplasts reflect blue and red light.

Tags

NGSS.HS-LS1-5

If a plant is exposed to light, which colour of light would lead to the lowest rate of oxygen release by a green plant?

• Blue

• Red

• Green

• White

Tags

NGSS.HS-LS1-5

What does the R_f value in thin layer chromatography represent?

• A. The distance travelled by the pigment front in a fixed time period

• B. The distance from the origin to the solvent front at the end of the experiment

• C. The ratio of distances travelled by the pigment and solvent fronts

• D. The concentration of the pigment applied to the chromatography plate

Plants produce carbon dioxide in respiration and use carbon dioxide in photosynthesis. The graph shows the volume of carbon dioxide exchanged in a plant at different light intensities. What is shown by the graph?

• A. There is no photosynthesis between W and X.

• B. There is no photosynthesis between Y and Z.

• C. There is more respiration than photosynthesis between Y and Z.

• D. There is more respiration than photosynthesis between W and X.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5