Adaptations, Part 1 - Vocabulary Flashcards

Allele

One of two or more alternative forms of a gene at a given locus.

Genetic variation

Differences among individuals in the genetic makeup (alleles) of a population.

Phenotype

Observable traits produced by the interaction of genotype and environment.

Natural selection

Differential survival and reproduction leading to changes in allele frequencies over time.

Adaptation

Heritable trait that increases fitness under a specific set of environmental conditions.

Fitness

Reproductive success; the contribution of an individual’s genes to the next generation.

Abiotic template

Non-living environmental factors (e.g., temperature, water) that drive adaptations.

Endotherm

An organism that maintains body temperature through metabolic heat; usually high energy needs.

Ectotherm

An organism whose body temperature is determined by the environment; heat balance can be behaviorally regulated.

Homeotherm

An organism that maintains a relatively constant body temperature.

Poikilotherm

An organism with a body temperature that varies with the environment.

Thermoregulation

Process of maintaining a stable body temperature.

Trade-off

A compromise where benefits in one trait come at a cost in another trait.

Insulation

Materials (fat, fur) that reduce heat loss and/or gain.

Evaporative cooling

Cooling achieved through evaporation of water (e.g., sweating, panting).

SA:V ratio

Surface area to volume ratio; affects heat exchange and water loss.

Isozymes

Different forms of an enzyme with different optimal temperatures.

Behavioral adaptation

Adaptations expressed as changes in behavior to improve survival.

Morphological adaptation

Structural changes in an organism’s form (e.g., leaf hairs, thick cuticles).

Physiological adaptation

Internal bodily function changes (e.g., enzyme activity, kidney efficiency).

Tawny owl color morphs

Brown and gray color variants affecting camouflage in different environments.

Color morph camouflage

Variation in coloration that influences how well an organism blends with its surroundings.

C3 photosynthesis

Most common carbon fixation pathway; uses Rubisco and is susceptible to photorespiration when CO2 is low.

Photorespiration

Process that reduces photosynthetic efficiency when Rubisco fixes O2 instead of CO2.

C4 photosynthesis

Carbon-concentrating pathway with two sites; reduces photorespiration; common in hot, dry environments.

CAM photosynthesis

Crassulacean acid metabolism; stomata open at night to save water; stored CO2 used in daytime.

Water use efficiency

Carbon gained per unit of water lost; higher efficiency conserves water.

Osmoregulation

Maintenance of proper salt and water balance relative to the environment.

Stomata

Pores on leaf surfaces that regulate gas exchange and water loss.

Leaf hairs (trichomes)

Hair-like structures that can reduce sunlight exposure and evaporation.

Waxy cuticle

A protective waxy layer limiting water loss through the leaf surface.

Deep roots

Long vertical roots reaching deeper water sources (water table).

Surface (shallow) roots

Roots near the soil surface to collect water from rainfall and surface moisture.

Hibernation

A state of prolonged inactivity to conserve energy during unfavorable conditions.

Diapause

A hormone-regulated pause in development allowing survival during adverse seasons.

Relative kidney size

The size of kidneys relative to body size, linked to water conservation strategies.

Hyperosmotic urine

Urine with high solute concentration to minimize water loss.

Kangaroo rat adaptations

Desert-adapted features such as efficient kidneys and nocturnal habits to conserve water.

Stomatal regulation

Control of stomatal opening to balance CO2 uptake with water loss.

Thermal performance curve

Graphical representation of how performance (e.g., sprint speed) changes with temperature.

Photorespiration risk in hot climates

High temperatures raise O2 competition