A biome is a large community of plants and animals that occupy a distinct region. The biome's distribution depends on the amount of sunlight (insolation), temperature, and precipitation (rainfall). This distribution helps define the different types of biomes on earth, such as tropical rainforests, deserts, and tundras.

For instance, imagine the world like a huge chocolate cake. Each slice of the cake represents a different biome, with its unique recipe of sunlight, rainfall, and temperature!

Let's zoom into one of the slices of our 'biome cake' and see what makes it so unique!

• Distribution: The tropical rainforests are found in a 'hot and humid belt' located between the Tropics of Cancer and Capricorn (23.5° N and S). This area is like a party zone where it's summer all year round with lots of rain and plenty of sunlight. There are no seasons, so the insolation level remains high throughout the year. Think of it like an everlasting tropical beach party with lots of green friends (plants)!

• Structure: This all-year-long party supports a complex structure of life. Like a multi-storied building, the rainforest has many layers from ground level to canopy to emergent plants, trees of up to 50 metres, and lower layers of shrubs and vines. It's like living in a huge 'green mansion' with different rooms occupied by unique creatures!

• Relative productivity: The rainforest has a high productivity rate due to high levels of photosynthesis (plants converting sunlight into food). It's like a bustling kitchen constantly cooking up life!

Sometimes, the productivity or 'cooking rate' can be limited due to:

• Cold temperatures in autumn and winter, which are like 'party poopers' ending the growing season.
• Limited annual rainfall (e.g. less than 250mm per year), which can leave the plants thirsty.
• Uneven seasonal distribution of rainfall throughout the year, which can disrupt the 'rhythm' of the plants' growth.
• Frozen soil and snow cover during winter months, which are like putting a 'lockdown' on the soil, making it inaccessible for plant roots.