Adaptation to the Environment

Practice flashcards covering topics on environmental adaptation, fundamental vs. realized niches, thermoregulation, osmoregulation, and organismal tolerance.

What three domains of life are created from prokaryotic and eukaryotic cell types?

Bacteria, Archaea, and Eukarya.

Which of the three domains of life are classified as prokaryotic?

Bacteria and Archaea.

How is an adaptation defined in terms of organismal fitness?

An adaptation is an environment- and condition-specific trait that increases an organism's fitness and may act as a driver of speciation.

What is the definition of a species' niche?

The role of a species in its community, which may be narrow and specialized or broad and general.

What is a fundamental niche?

The full range of environmental conditions that a species can physically tolerate.

Based on this species tolerance curve, what bounds define the range outside of which no organisms can survive?

The lower tolerance limit and upper tolerance limit, which mark the boundary into the Zone of Intolerance.

What specific temperature limits constrain the fundamental niche of sugar maple trees?

Sugar maple trees cannot tolerate average monthly high temperatures above $24$ to $27,^\bullet\text{C}$ or winter temperatures below $-18,^\bullet\text{C}$.

What is a realized niche, and what factors determine it?

The range of environmental conditions that a species actually manages to exploit, determined by its fundamental niche plus species interactions.

According to the provided niche comparison diagram, what two ecological factors restrict the realized niche of the fish?

Prey species being unable to tolerate high salinity, and parasites being common at high temperatures.

What structural adaptations have organisms evolved to survive in cold climates versus hot climates?

In cold climates, organisms evolve heat-conserving structures such as fur, feathers, blubber, and fat; in hot climates, organisms evolve mechanisms to shed excess heat, such as perspiration in humans and panting in dogs.

What behavioral adaptations allow organisms to survive in regions with fluctuating temperatures?

Migration, hibernation, and torpor.

What anatomical features do plants utilize to reduce water loss?

Waxy cuticles and leaf hairs.

What adaptations help terrestrial animals conserve water or manage extreme heat?

High dehydration tolerance (e.g., camels), seeking cooler shelter, and nocturnal activity.

Which soil characteristics directly affect plant distribution and abundance?

Soil structure, pH, and nutrient content.

What is homeostasis, and what two main regulatory mechanisms maintain it in animals?

Homeostasis is the relatively stable internal state maintained inside an animal's body, regulated primarily by thermoregulation and osmoregulation.

How do ectotherms and endotherms differ in how they manage body temperature?

Ectotherms do not internally control their body temperature and rely on environmental temperatures, whereas endotherms maintain a constant internal temperature despite external changes.

What are examples of behavioral and circulatory adaptations found in ectotherms?

Behavioral adaptations include turtles sunbathing and lizards burrowing; circulatory adaptations include countercurrent exchange in fish to transfer heat rapidly from arteries to veins.

In fish gills, what anatomical structures carry out gas and heat exchange as water flows over them?

Lamellae located on gill filaments attached to the gill arch.

How does vasoconstriction help endotherms preserve body heat in cold conditions?

It constricts peripheral blood vessels to reduce superficial blood flow and force blood toward vital internal organs.

What is the difference between osmoconformers and osmoregulators?

Osmoconformers match their internal body osmolarity to their surrounding environment, while osmoregulators maintain an internal osmolarity distinct from their external environment.

How do marine iguanas regulate osmotic balance when consuming saltwater environments?

They utilize specialized salt-secretion adaptations to excrete extra salt and control water loss.

What role do stomata play in plant osmoregulation and gas exchange?

Stomata open to take in $\text{CO}_2$ for photosynthesis and close to conserve $\text{H}_2\text{O}$ and reduce transpiration.

Which plant cell organelle specifically helps hold onto water to assist in plant osmoregulation?

The vacuole.