A population of shore crabs is found under stones in the upper intertidal zone of a rocky coast. What is the best description of the habitat?

What is an adaptation?

Marram grass, Ammophila arenaria, grows on coastal sand dunes. What feature helps it reduce water loss in windy conditions?

What condition is required for strong coral reef formation?

A field guide describes a beetle as living in “woodland”.

Grey mangrove, Avicennia marina, grows in waterlogged mud. What is the role of pneumatophores?

An aquatic insect is absent from stagnant ponds but abundant in fast-flowing streams. What abiotic variable is most likely limiting its distribution?

On a biome climate graph, mean annual temperature is plotted against annual precipitation. Which biome is most likely at very low precipitation and high temperature?

Merriam’s kangaroo rat, Dipodomys merriami, is nocturnal and produces very concentrated urine. What environmental problem do these adaptations address?

The kapok tree, Ceiba pentandra, has buttress roots. What is their main adaptive value in tropical rainforest?

Marram grass, Ammophila arenaria, is common on coastal sand dunes.

A student records factors affecting a pond snail population.

Reef-building corals contain photosynthetic algae in their tissues.

A biome climate graph uses mean annual temperature on the x-axis and annual precipitation on the y-axis.

The red-eyed tree frog, Agalychnis callidryas, lives in tropical rainforest.

Students sampled marram grass, Ammophila arenaria, along a transect from the seaward edge of a sand dune inland. At each station they measured soil moisture and percentage cover of marram grass.

The graph shows the growth rate of reef-building coral fragments kept under different water clarity and depth conditions.

The table compares water loss from leaves of two desert plant species under the same conditions.

A student finds that a plant is abundant only where soil pH is below 5.5 along a transect. What conclusion is most justified?

A river floods a coastal bay with suspended clay and freshwater for several weeks. What effect on nearby reef-building corals is most likely?

Cacti in North America and some euphorbs in Africa have succulent stems and spines but are distantly related. What process best explains this similarity?

A fish feeds widely as an adult but breeds only in shallow gravel beds with high dissolved oxygen. What is the best ecological interpretation?

On a tolerance curve for temperature, what does the zone of physiological stress indicate?

Two regions have similar mean annual temperature and precipitation but are on different continents. What is most likely about their natural ecosystems?

Red-eyed tree frogs, Agalychnis callidryas, lay eggs on leaves above pools. What is the adaptive advantage?

Students plan a belt transect across a meadow edge to investigate whether a small herb is associated with soil pH.

Unrelated shrubs in hot deserts on different continents often have small tough leaves and extensive roots.

Grey mangrove, Avicennia marina, grows in saline, waterlogged mud.

A tolerance curve shows abundance of a species against soil salinity.

Ocean acidification lowers seawater pH.

Compare the abiotic conditions of tundra and hot desert biomes.

Compare adaptations of Larrea tridentata and Ceiba pentandra to their environments.

A climate diagram plots six sites on axes of mean annual temperature and annual precipitation. The sites are labelled with their natural vegetation.

A survey recorded the presence of a freshwater mayfly nymph at stream sites with different dissolved oxygen concentrations.

A freshwater mussel is found only in cool, fast-flowing streams with stony beds.

A student concludes that light intensity causes the distribution of moss along a woodland transect because moss cover is greatest in shaded quadrats.

Grasslands occur on several continents and often contain different grass species but similar grazing communities.

Students measured percentage cover of a woodland moss and light intensity at 20 quadrats along a path-to-forest transect.

Coral fragments were grown for 12 weeks at different temperatures. The number of algal cells remaining in coral tissue and calcium carbonate deposition were measured.

The graph shows projected shifts in biome zones along a mountain slope after an increase in mean annual temperature.

A camera-trap study recorded activity of Merriam’s kangaroo rat, Dipodomys merriami, at a desert site over 24 hours. Air temperature and relative humidity were also recorded.

Marram grass, Ammophila arenaria, is found on coastal sand dunes.

Coral reefs form only in some marine environments.

Terrestrial biomes are associated with characteristic climates.

Hot deserts and tropical rainforests both have high temperatures but present different adaptive challenges.

The figure compares unrelated plant species from hot deserts in two continents and plants from nearby wetter habitats.

A class used transects to investigate whether soil pH limits the distribution of a plant species in a semi-natural grassland.

Ecosystems in the same terrestrial biome can occur on different continents.

Sand dunes and mangrove swamps both challenge plants, but in different ways.

A coastal development proposal would increase sediment runoff into a shallow tropical bay that currently contains coral reefs.