Final Exam Study Guide

Photosynthesis

The process by which plants convert light energy into chemical energy.

Palisade mesophyll

Layer of cells in a leaf that allows deep penetration of light for photosynthesis.

Root hairs

Extensions of root cells that increase surface area for nutrient and water uptake.

Phloem sugar transport

The movement of sugars through the phloem, involving active loading and osmotic pressure.

Latent heat

Energy absorbed or released during a phase change without a change in temperature.

Vapor pressure deficit (VPD)

The difference between the amount of moisture in the air and the maximum amount of moisture that the air can hold.

Radiation use efficiency

The efficiency with which plants convert absorbed light into biomass.

Nodule

A structure formed in legume roots by Rhizobia bacteria for nitrogen fixation.

Mycorrhiza

A symbiotic association between fungi and plant roots that enhances nutrient uptake.

Virulence

The degree of pathogenicity of a microorganism.

Greenhouse gases

Gases in the atmosphere that trap heat, including carbon dioxide, methane, and water vapor.

C₄ photosynthesis

A photosynthetic pathway that is more efficient in hot and dry environments than C₃ photosynthesis.

Rubisco

The enzyme that catalyzes the first step of carbon fixation in photosynthesis and is the most abundant protein on Earth.

Meristem

A region of actively dividing cells responsible for plant growth.

Harvest index

The ratio of economic yield (e.g., grain) to total biological yield (e.g., total plant mass).

Empirical model

A model based on observed data trends rather than underlying biological mechanisms.

Mechanistic model

A model that describes the biological mechanisms driving observed phenomena.

Casparian strip

A structure in root tissue that controls water and nutrient uptake by forcing substances through selective membranes.

Clonal propagation

The process of producing new plants from a parent plant through vegetative means to ensure uniformity.

Light compensation point

The point at which the rate of photosynthesis equals the rate of respiration.

Essential macronutrients

Nutrients necessary for plant growth, including Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S).