2nd Botany Exam Ultimate Study Guide

Phenology

The formal study of the timing of recurring biological and natural events.

Photoperiodism

The biological capacity of an organism to measure day length and synchronize developmental transitions.

Short-Day Plants

Plants that are induced to flower when day length drops below a species-specific critical threshold.

Long-Day Plants

Plants that are induced to flower during the summer months, requiring longer light intervals.

Day-Neutral Plants

Plants that transition from vegetative to reproductive growth independently of photoperiod.

Transpiration

Evaporative loss of water vapor from the aerial organs of a plant.

Stomatal Regulation

The opening and closing of stomatal pores through osmotic turgor fluctuations within guard cells.

Cohesion-Tension Theory

A framework explaining the upward movement of sap in plants based on evaporation and water cohesion.

Hydraulic Redistribution

The passive transfer of soil water from wet to dry soil layers mediated by plant root architectures.

Sapwood

The younger, outer region of secondary xylem that participates in active water and ion transport.

Heartwood

The older, central core of non-functional secondary xylem that acts as a deposition sink for toxic secondary metabolites.

Nutrient Recycling

The process of remobilizing nutrients during autumn senescence as plants prepare for winter.

Essential Mineral Nutrients

Elements required for plant growth, including macronutrients and micronutrients.

Liebig's Law of the Minimum

States that growth is constrained by the scarcest nutrient relative to physiological demand.

Periderm

A protective tissue layer formed by the cork cambium consisting of phellem, phellogen, and phelloderm.

Dendrochronology

The science of dating historical events using tree rings.

Intercalary Meristems

Meristems located at the base of internodes and leaf sheaths in monocots that drive vertical elongation.

Cavitation

The rupture of the liquid column in the xylem when negative pressure exceeds the cohesive strength of water.

Ammonification

The process of converting organic nitrogen into ammonium by soil fungi and bacteria.

Nitrification

The oxidation of ammonium to nitrite, and then to nitrate by specialized bacteria.