BCH3004- Photosynthesis

The process by which plants convert light energy into chemical energy (glucose) using chlorophyll and other pigments.

The first stage of photosynthesis, where light energy is captured by chlorophyll and converted into chemical energy in the form of ATP and NADPH.

The second stage of photosynthesis, where carbon dioxide is converted into glucose using the energy from ATP and NADPH.

The main pigment in plants that absorbs light energy, primarily in the blue and red wavelengths.

A group of pigments that absorb light energy and transfer it to chlorophyll a, which is the primary pigment responsible for photosynthesis.

A process that occurs in the thylakoid membranes of chloroplasts, where light energy is used to create a proton gradient, which drives the production of ATP.

The process by which carbon dioxide is converted into glucose using the energy from ATP and NADPH in a series of enzymatic reactions.

A process that occurs in plants when oxygen is present, where the enzyme rubisco reacts with oxygen instead of carbon dioxide, leading to a loss of energy and reduced glucose production.

A specialized complex within chloroplasts responsible for capturing light energy and converting it into chemical energy.

The reaction center of Photosystem II, with a peak absorption wavelength of 680 nm.

A process that occurs in the thylakoid membranes of chloroplasts, where water is split, releasing oxygen and hydrogen ions.

The complex of proteins and pigments that captures light energy in Photosystem II.

The specialized molecule at the core of the LHC, where energy is transferred and photosynthesis begins.

The protein-bound pigment molecules within the LHC, absorbing light energy and transferring it to the reaction center.

The process where the absorbed light energy excites an electron in a chlorophyll molecule, raising it to a higher energy level.

The unstable state of a chlorophyll molecule after absorbing light energy, where the electron is at a higher energy level.

The process where the excited electron in a chlorophyll molecule returns to its ground state, releasing energy.

A type of photosynthesis where the electrons flow in a cycle from photosystem I back to the cytochrome complex, generating ATP but not NADPH or oxygen.

Cyclic photophosphorylation uses only photosystem I.

The electron from ferredoxin returns to the cytochrome complex in cyclic photophosphorylation.

Cyclic photophosphorylation does not produce NADPH or oxygen.

Cyclic photophosphorylation generates ATP.

Non-cyclic photophosphorylation produces NADPH, ATP, and oxygen.

The Calvin cycle uses more ATP than NADPH.

The concentration of NADPH in the chloroplast influences the choice between non-cyclic and cyclic photophosphorylation.

An increase in NADPH stimulates a shift from non-cyclic to cyclic electron flow.

Cyclic photophosphorylation helps to balance ATP and NADPH production, ensuring proper functioning of the Calvin cycle.

The arrangement of cells in C4 plants where bundle sheath cells are surrounded by mesophyll cells, facilitating efficient carbon dioxide fixation.

A photosynthetic pathway that uses an initial carbon fixation step to produce 4-carbon organic acids, minimizing photorespiration and increasing efficiency in hot, dry environments.

An enzyme that catalyzes the conversion of pyruvate to phosphoenolpyruvate in the C4 pathway, providing the substrate for initial CO2 fixation.

A metabolic pathway found in plants that fix carbon dioxide at night when stomata are open, storing it as organic acids and releasing it during the day for photosynthesis.

An enzyme that decarboxylates malic acid, releasing carbon dioxide for the Calvin cycle, and is involved in both C4 and CAM pathways.

C3 plants use this enzyme to fix carbon dioxide, but under certain conditions, it can also bind to oxygen instead.

When Rubisco binds to oxygen instead of carbon dioxide, it leads to a process called photorespiration, resulting in a loss of energy and decreased photosynthetic efficiency.

Photorespiration occurs when stomata are closed to conserve water, leading to lower carbon dioxide levels inside the leaf. This forces Rubisco to bind to oxygen instead of carbon dioxide.

This process involves a series of reactions that convert the compound produced from Rubisco's reaction with oxygen (phosphoglycolate) into glycine, which then releases carbon dioxide. This process consumes ATP and produces no sugar, decreasing the plant's photosynthetic output.

C4 plants have evolved a mechanism to minimize photorespiration, using an alternative carbon fixation pathway that produces a four-carbon compound initially, before entering the Calvin cycle. This process involves specialized cells and enzymes.

In C4 plants, these cells surround the veins of the leaf and are specialized for the Calvin cycle. They receive the four-carbon compound produced in the initial fixation step.

These cells are specialized for the initial carbon fixation step in C4 plants, producing a four-carbon compound that then gets transported to the bundle sheath cells.

These plants are named for the four-carbon compound produced in the initial carbon fixation step instead of the usual three-carbon compound produced by C3 plants. They are well-adapted to hot and arid conditions.

This process involves a different carbon fixation pathway utilized by some plants, especially those adapted to arid environments. It involves storing carbon dioxide during the night and releasing it during the day to minimize water loss during photosynthesis.

This is the most common type of photosynthesis, employed by most plants, where carbon dioxide is initially fixed into a three-carbon compound. It is efficient in cool and wet climates but less so in hot and dry conditions.