Photosynthesis and Plant Hormones Overview

These flashcards cover key vocabulary and concepts related to photosynthesis and plant hormones as discussed in the lecture notes.

Photosynthesis

A process that uses solar energy, carbon dioxide, and water to produce energy-storing carbohydrates, generating oxygen as a waste product.

Light-dependent reactions

The first stage of photosynthesis occurring in the thylakoid membranes where light energy is converted into ATP and NADPH.

Calvin cycle

The second stage of photosynthesis that occurs in the stroma, using ATP and NADPH to convert carbon dioxide into glucose.

Chloroplasts

Organelles in plant cells where photosynthesis occurs, consisting of an outer membrane, inner membrane, and thylakoids.

Redox reactions

Chemical reactions that involve the transfer of electrons, with reduction referring to the gain of electrons and oxidation to the loss of electrons.

Photophosphorylation

The process of generating ATP from ADP and inorganic phosphate, powered by light energy during photosynthesis.

Autofixation

The process of carbon fixation where CO2 is added to an organic molecule during the Calvin Cycle.

Glycolysis

The initial step in cellular respiration that breaks down glucose into pyruvic acid, yielding a small amount of energy.

Auxin

A plant hormone that regulates growth, including root initiation and apical dominance.

Ethylene

A gaseous plant hormone that plays a role in fruit ripening and plant stress responses.

C3 plants

Plants that use the standard Calvin Cycle, primarily effective in cool and moist conditions.

C4 plants

Plants that initially fix carbon dioxide into a 4-carbon compound, allowing them to thrive in hot, dry environments.

CAM plants

Plants that fix carbon dioxide at night, storing it as an acid to reduce water loss in arid environments.

Photosynthetically Active Radiation (PAR)

The spectral range of solar radiation (400-700 nanometers) that photosynthetic organisms can use.

Limiting Factors in Photosynthesis

Environmental conditions such as light intensity, temperature, and CO2 concentration that restrict the rate of photosynthesis.

Photoperiodism

The physiological response of plants to the lengths of light and dark periods, influencing flowering.