Photosynthesis & Respiration

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll, converting carbon dioxide and water into glucose and oxygen.

Light-dependent reactions

Reactions that occur in the thylakoid membrane of chloroplasts during photosynthesis. They require light energy to convert ADP and NADP+ into ATP and NADPH, respectively. These reactions also produce oxygen as a byproduct.

Light-independent reactions (Calvin cycle)

The series of chemical reactions in photosynthesis that convert carbon dioxide into glucose molecules. It occurs in the stroma of chloroplasts and does not require light energy. The cycle involves three main steps: carbon fixation, reduction, and regeneration of the starting molecule.

Carbon fixation

The process of incorporating carbon dioxide into organic compounds during the Calvin cycle of photosynthesis.

Factors Affecting Photosynthesis

Various environmental conditions, including light intensity, temperature, carbon dioxide concentration, and water availability, that influence the rate of photosynthesis in plants.

Production of oxygen

One of the significant outcomes of photosynthesis, where oxygen is released as a byproduct during the light-dependent reactions.

Leaf adaptations

The specialized adaptations of leaves, such as their shape, size, and arrangement, that optimize the absorption of sunlight for photosynthesis.

Chloroplast distribution

The strategic arrangement of chloroplasts within plant cells to maximize exposure to light for efficient photosynthesis.

Stomatal control

The regulation of stomatal openings in plant leaves to control the exchange of gases, including carbon dioxide and oxygen, for optimal photosynthesis.

Cyanobacteria

Photosynthetic prokaryotic organisms that can carry out photosynthesis similar to plants and algae, playing a crucial role in Earth's ecosystems.

Photon

A packet of light.

Chlorophyll

The light-absorbing green-coloured pigment that begins the process of photosynthesis.

Chloroplast

A membrane-bound organelle in green plant and algal cells that carries out photosynthesis.

Stroma

The protein-rich semiliquid material in the interior of a chloroplast.

Thylakoid

A disk-shaped sac in the stroma of a chloroplast.