SAPLING CH 5 HW

Which statement accurately describes the Calvin cycle?

The Calvin cycle is a light-independent metabolic pathway occurring in the chloroplast stroma that converts carbon from carbon dioxide into sugar.

Which statement describes the function of photosynthetic pigments in leaves?

They capture light energy and remove electrons from a donor.

Label the components of a chloroplast

(from top to bottom) - double membrane - granum - thylakoid - stroma

Many eukaryotic organisms rely on the process of photosynthesis and cellular respiration to sustain life. Choose the statements that accurately describe the two processes.

- Both processes are capable of forming ATP for use as an energy source. - Chloroplasts participate in one process and mitochondria participate in the other. - Oxygen is a reactant in one process and a product in the other process.

Choose all the events that occur during the light-dependent reactions of photosynthesis.

- H+ ions are used to help produce the energy carriers, ATP and NADPH. - Excited electrons help move H+ ions to create a concentration gradient. - Light energy is used to excite electrons on specific chlorophyll molecules.

Both photosynthesis and cellular respiration are cellular processes that involve glucose. How do these two processes differently affect the metabolism of glucose?

Glucose is produced during photosynthesis to hold the energy gathered from light, whereas glucose is broken down during cellular respiration to release stored cellular energy.

What is the source of the electrons that replace the excited electrons lost from chlorophyll?

H2O

The events below are parts of the overall process of photosynthesis. For each event, identify the chloroplast structure that facilitates the event.

Light-dependent reactions: - thylakoid membrane CO2-dependent reactions: - stroma Calvin cycle: - stroma oxygen production: - thylakoid membrane

The light-independent reacts of photosynthesis, also known as the Calvin cycle, use and produce a variety of molecules. Sort the molecules below into three categories: molecules brought in and used in the Calvin cycle, molecules produced during the Calvin cycle that leave the cycle, and molecules used and regenerated within the Calvin cycle.

Molecules brought in and used in the Calvin cycle: - CO2 - NADPH Molecules produced during the Calvin cycle that leave the cycle: - NADP+ - a few of the glyceraldehyde 3-phosphate (G3P) Molecules used and regenerated within the Calvin cycle: - most of the glyceraldehyde 3-phosphate (G3P) - ribulose biphosphate (RuBP)

Which of the products of photosynthesis are used for cellular respiration?

- carbohydrates - oxygen

Plants synthesize their own food in the form of sugars during the process of photosynthesis. Which of the following statements describe photosynthesis?

- produces sugars for the plant using only the energy from the sunlight - is a cellular process that occurs in the chloroplasts of plant cells - converts carbon dioxide sugars, releasing oxygen

How do chlorophyll pigments absorb energy from light?

A photon excites an electron in the chlorophyll to a higher energy state.

Classify these organisms according to the metabolic processes they perform.

Cellular respiration, but not photosynthesis: - tigers - lizards - mushrooms Both photosynthesis and cellular respiration: - dandelions - seaweed

Classify each description as applying to either autotrophs or heterotrophs.

Autotrophs: - producers - many use photosynthesis to produce organic compounds - use inorganic materials to produce energy - make their own food Heterotrophs: - obtain their food by consuming other organisms - rely on other organisms for energy - consumers - unable to produce organic compounds from inorganic materials

During photosynthesis, specific pigments absorb light energy, which is then used to fuel the building of sugar molecules, Which colors correspond to the wavelengths of light that are strongly absorbed by each pigment?

Carotenoids: - violet-blue Chlorophyll b: - orange-red - violet-blue Chlorophyll a: - orange-red - violet-blue

The light-independent reactions of photosynthesis, also called the Calvin cycle, use and produce a variety of molecules. Sort the molecules below into three categories, molecules brought in and used in the Calvin cycle, molecules produced during the Calvin cycle that leave the cycle, and molecules made in the cytoplasm from the products of the Calvin cycle.

Molecule brought in and used in the Calvin cycle: - carbon dioxide from the environment - energy-carrier molecules formed in the light-dependent reactions Molecules produced in the Calvin cycle that leave the cycle: - energy-rich 3-carbon molecules - energy-carrier molecules that have lost some energy Molecules made in the cytoplasm from the products of the Calvin cycle: - glucose and other organic molecules

The light-independent reactions of photosynthesis, also known as the Calvin cycle, must repeat three times in order for a cell to have enough material to construct half a glucose molecule. A variety of molecules are used and produced during this process. Sort the molecules below into three categories; molecules brought in and used in three turns of the Calvin cycle, molecules produced during three turns of the Calvin cycles that leave the cycle, and molecules used and regenerated within the Calvin cycle during three turns.

Molecules brought in and used in three turns of the Calvin cycle: - 3 CO2 - 6 NADPH - 9 ATP Molecules produced in three turns of the Calvin cycle that leave the cycle: - 1 G3P - 6 NADP+ + 6H+ - 9 ADP Molecules used and regenerated within the Calvin cycle in three turns: - 3 RuBP - 5 G3P

The process of photosynthesis and cellular respiration involve many of the same substances. Which of the following are involved only in photosynthesis, which are involved only in cellular respiration, and which take part in both?

Photosynthesis only: - chloroplasts - sunlight Cellular respiration only: - mitochondria Both: - electron transport chain - oxygen (O2)

Complete the photosynthesis reactions by placing the following items as reactants, energy sources, or products of these reactions.

Photosynthesis reactants: - 6 CO2 - 6 H2O Energy source: - light Photosynthesis products: - C6H12O6 - 6 O2

Complete the photosynthesis reaction by placing the following compounds and energy sources into the reaction as reactants or products.

Photosynthesis reactants: - carbon dioxide - water - light energy Photosynthesis products: - oxygen - simple sugars

Which of the following scenarios is a direct effect of the absence of carbon dioxide during photosynthesis?

The carbon fixation stage of the Calvin cycle would be unable to synthesize the sugar 3-PGA.

What provides the energy that excites the electrons in the chlorophyll molecules?

light

Select the component of chloroplast that is the site of light-dependent reactions.

thylakoids