Adaptation to environment

An organism's **role** in its ecosystem: the **abiotic conditions** it tolerates, **how it obtains food/energy**, and its **interactions** with other species.

The **habitat** is **where** an organism lives (its address); the **niche** is **what it does** there and the conditions it needs (its job).

A **non-living**, physical or chemical feature of the environment (e.g. temperature, light, pH, dissolved oxygen, salinity).

A condition created by **other living organisms** (e.g. food supply, predators, competitors, disease).

The span of an abiotic factor an organism can survive in — best in the **optimum range**, stressed in the **zones of stress**, and **absent** beyond the **limits of tolerance**.

It is **most abundant and active** — the conditions are ideal for it.

It is **absent** — it cannot survive there at all.

An organism that **must have oxygen** to survive, because it relies on **aerobic respiration** to release energy.

An organism for which **oxygen is toxic**; it survives **only where oxygen is absent** (e.g. waterlogged mud).

It must carry out **aerobic respiration** to release enough energy, and aerobic respiration **requires oxygen**.

**Dissolved oxygen** — needed for aerobic respiration (for an obligate aerobe).

It is **absent** there, however good the other conditions are.

A **non-living**, physical or chemical feature of a habitat — e.g. temperature, water, light, pH or salinity.

A **living** influence on a habitat — e.g. predators, competitors, food or disease.

**Temperature, water (moisture), light, pH and salinity** (also oxygen, wind, soil minerals).

The **span of values** of an abiotic factor over which a species can **survive**; outside it, the species is absent.

It is most **abundant** — conditions suit it best and its cell processes work well.

The species is **absent** — the factor is too high or too low for it to survive.

The one factor in **short (or excess) supply** that holds a species back and stops it living in a place.

It sets the rate of **enzyme-controlled reactions**; extremes **denature** proteins, so a species is absent where it is too hot or too cold.

Light is needed for **photosynthesis**, so plants are limited to places with **enough light** (e.g. not in deep shade or deep water).

Too **little** water causes dehydration; too **much** can drown roots — so each species is restricted to a moisture range it tolerates.

Name a specific **abiotic factor** AND give the **reason** for its effect — a bare list of factors only scores half.

It lives only where the **abiotic conditions stay within its range of tolerance**; outside those limits it cannot survive.

A **large region** with a particular **climate** and a **characteristic community** of organisms (e.g. tropical rainforest, tundra).

**Temperature** and **precipitation** (rainfall).

The typical pattern of **temperature and precipitation** in a region, averaged over many years.

A **non-living** physical or chemical feature of the environment (e.g. temperature, rainfall, light, soil).

**Hot desert** — sparse, drought-adapted plants.

**Tropical rainforest** — dense, tall evergreen trees.

**Tundra** — low mosses, lichens and small shrubs.

**Temperate forest** — deciduous broadleaf trees.

Read **both** coordinates (its temperature AND its rainfall) and match them to the biome whose climate fits.

Climate sets the **vegetation** that can grow, and the vegetation decides which **animals** can live there.

Plants are the base of the community and are limited most by **how warm it is** and **how much water** there is.

They differ in **rainfall**: the desert is very dry (sparse plants) and the rainforest is very wet (dense trees).

A **feature** (structural, physiological or behavioural) that helps an organism **survive and reproduce** in its environment.

A plant adapted to live where **water is scarce**, such as a hot desert (e.g. a cactus).

A plant adapted to live in **salty conditions**, such as a mangrove tree in a coastal swamp.

**Thick waxy cuticle**, **reduced leaf area** (spines/needles), and **sunken stomata** — all reduce water loss.

They trap a layer of **humid air** in pits, lowering the water-vapour gradient so **less water escapes**.

Gas exchange then happens when it is **cooler**, so **less water is lost** than during the hot day (CAM).

It **stores water** taken up during rare rains, for use through long dry periods.

**Aerial 'breathing' roots** of mangroves that grow into the air to **take in oxygen**, because the swamp mud is oxygen-poor.

They **excrete excess salt**, keeping internal salt low so water can still be **absorbed by osmosis**.

It contains **very little oxygen**, so the roots struggle to **respire** — solved by aerial roots.

Any two of: **bright colourful petals**, **scent**, sugary **nectar**, a **shape** that fits the pollinator.

Name the **problem** (e.g. losing water, no oxygen, too much salt), then the adaptation is whatever **solves it**.

A feature that helps an organism **survive and reproduce** in its particular environment.

**Structural** (body parts), **physiological** (internal processes) and **behavioural** (actions).

A physical **body feature** — its shape, size or parts. Example: a fennec fox's **large ears** that lose heat.

A way the body **works on the inside**. Example: making very **concentrated urine** to save water.

Something the animal **does** (an action or habit). Example: **sheltering in a burrow** during the midday heat.

Structural: **large ears** to lose heat. Physiological: **concentrated urine** to save water. Behavioural: being **active at night**.

Structural: **thick fur and blubber**, small ears. Physiological: **shivering**. Behavioural: **huddling** or **migrating**.

**Grinding teeth**, a **long gut**, **gut microbes** that digest cellulose, and **long feeding times**.

The microbes digest **cellulose** in plant cell walls, which the animal's own enzymes cannot break down.

Staying **alert (vigilant)**, feeding **in a group**, and feeding **near cover** or at dawn/dusk.

You must add the **benefit** — large ears, **which lose heat** and keep the animal cool. Name the feature AND say how it helps.

**Suggest** — apply the idea of adaptation to a **new animal** and give a plausible, reasoned answer.