practice photo cell respiration

Three main stages of photosynthesis

Capturing sunlight energy, producing ATP and NADPH, and using these to make carbohydrates from CO₂.

Part of the chloroplast containing thylakoids

the stroma

Grana

Stacks of thylakoid membranes in a chloroplast.

Two main stages of photosynthesis

Light-dependent reactions and light-independent (Calvin cycle) reactions.

Primary pigment

Chlorophyll a.

Function of accessory pigments like carotenoids

To absorb light wavelengths chlorophyll doesn't and broaden light absorption.

Photons

Packets of light energy.

Colors of visible light absorbed best by chlorophyll

Blue and red.

Photosystem II

Water is split to replace lost electrons, producing O₂ and releasing H⁺ ions.

Photosystem I

Electrons are re-energized and used to reduce NADP⁺ to NADPH.

Role of the electron transport system (ETS) in photosynthesis

To transfer electrons and pump protons into the thylakoid space to create a proton gradient.

Process driving the synthesis of ATP in the thylakoid membrane

Chemiosmosis.

Final electron acceptor in photosynthetic electron transport

NADP⁺.

Enzyme responsible for fixing carbon in the Calvin cycle

Rubisco.

Effect of photorespiration on photosynthetic efficiency

Rubisco binds O₂ instead of CO₂, wasting energy and releasing fixed carbon.

Key adaptation of C₄ plants

They fix carbon in separate cell types (mesophyll and bundle-sheath cells) to minimize photorespiration.

How CAM plants conserve water

They open stomata at night to fix CO₂ and close them during the day.

Three stages of the Calvin cycle

Carbon fixation, sugar production, and RuBP regeneration.

CO₂ molecules needed to make one glucose molecule

Six.

Fate of ADP and NADP⁺ produced in the Calvin cycle

They are recycled back to the light-dependent reactions.

Type of reaction involving loss and gain of electrons

Redox (oxidation-reduction) reactions.

Location of glycolysis

In the cytoplasm.

Starting molecule for glycolysis

Glucose.

Final product of glycolysis

Two pyruvate molecules.

Substrate-level phosphorylation

The direct formation of ATP during enzyme-catalyzed reactions.

Net ATP gain from glycolysis

2 ATP.

What happens to pyruvate before entering the Krebs cycle

It is converted into acetyl-CoA.

Gas released during pyruvate oxidation

CO₂.

Location of the Krebs cycle

In the mitochondrial matrix.

Products of each turn of the Krebs cycle

3 NADH, 1 FADH₂, 1 ATP, and 2 CO₂.

Total ATP yield from one glucose molecule after complete aerobic respiration

About 36-38 ATP.

Main role of NADH and FADH₂ in respiration

To carry high-energy electrons to the electron transport chain.

Location of the electron transport chain

In the inner mitochondrial membrane.

Final electron acceptor in the electron transport chain

Oxygen (O₂).

Molecule formed when oxygen accepts electrons and protons at the end of the ETC

Water (H₂O).

What drives ATP synthase during chemiosmosis

The movement of protons (H⁺) down their concentration gradient.

Process allowing cells to make ATP when oxygen is not present

Fermentation.

End products of lactic acid fermentation

Lactate and NAD⁺.

End products of alcohol fermentation

Ethanol, CO₂, and NAD⁺.

Other molecules that can be broken down to produce ATP besides glucose

Fats and proteins (converted into intermediates that enter glycolysis or the Krebs cycle).