8.1 8.3 9.1

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?

• There is no photosynthesis between W and X.

• There is no photosynthesis between Y and Z.

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

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

Tags

NGSS.HS-LS1-5

NGSS.HS-LS1-7

NGSS.HS-LS2-5

The diagram shows a section through a thylakoid. Electrons move from X to Y. What do the letters X, Y, and Z represent?

• X: photosystem I

  Y: photosystem II

  Z: thylakoid space

• X: photosystem II

  Y: photosystem I

  Z: thylakoid space

• X: ATP synthase

  Y: photosystem II

  Z: stroma

• X: photosystem II

  Y: ATP synthase

  Z: stroma

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

Two reactions of the Krebs cycle are shown. What type of reactions are isocitrate and oxalosuccinate undergoing?

• Isocitrate: oxidation

  Oxalosuccinate: reduction

• Isocitrate: reduction

  Oxalosuccinate: decarboxylation

• Isocitrate: reduction

  Oxalosuccinate: oxidation

• Isocitrate: oxidation

  Oxalosuccinate: decarboxylation

Tags

NGSS.HS-PS1-4

The graph shows the percentage of stomata that are open in two different species of plants over a 24-hour period. What does this graph show about plants X and Y?

• Plant X absorbs most carbon dioxide at night.

• Plant Y is adapted to desert conditions.

• Plant X photosynthesis most at midday.

• Plant Y only respires during the day.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

What effect do changes in pH have on enzymes?

• All enzymes increase in activity as pH increases.

• The activity of all enzymes is reduced by a pH below or above 7.

• Low pH causes reversible denaturation in all enzymes.

• Extreme pH can alter the active site of all enzymes.

Which compound is a waste product of anaerobic respiration in humans?

• carbon dioxide

• ethanol

• lactate

• pyruvate

Tags

NGSS.HS-LS2-3

The grey line in each of the graphs below represents the rate of reaction catalysed by an uninhibited enzyme as substrate concentration is increased.

Which graph shows expected results if a competitive inhibitor was added to the reaction?

• A

• B

• C

• D

The diagram shows the link reaction between glycolysis and the Krebs cycle.

Which type of reaction is occurring?

• Pyruvate is carboxylated.

• CO₂ is oxidized.

• NAD⁺ is reduced.

• Pyruvate is phosphorylated.

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-3

Which structure in the chloroplast diagram is adapted to carry out chemiosmosis?

• A

• B

• C

• D

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

Which process is most responsible for the movement of water from roots to leaves of plants on a hot summer day?

• Active translocation of mineral ions in roots

• Active transport of organic compounds into sieve tubes

• Raised hydrostatic pressure gradients

• Evaporation of waster from mesophyll cell walls