The Living World Flashcards
Define ecosystem
All of the living and non-living components of an area
What does the nutrient cycle show?
How nutrients move through an ecosystem
Briefly explain the nutrient cycle [5]
- When dead material decomposes, nutrients are released into the soil
- The nutrients are then taken up from the soil by plants
- The plants may be eaten by consumers
- The plant or consumer dies
- The nutrients are returned to the soil
What does a food chain show?
What eats what
What does a food web show?
Lots of food chains and how they overlap
What is the climate like in tropical rainforests? [3]
- No definite seasons
- Hot (20 - 28°C)
- High rainfall (2000 mm per year)
Why isn’t the soil very fertile in tropical rainforests? [2]
- Heavy rain washes nutrients away
- High levels of biodiversity take up the nutrients in soil very quickly
What are plants like in tropical rainforests? [3]
- Evergreen trees
- Tall trees
- Thick vegetation
Why are most trees in tropical rainforests evergreen?
To help them take advantage of the continual growing season
Define biodiversity
The variety of organisms living in a particular area
What are the 4 layers of the rainforest?
- Forest floor
- Undercanopy
- Main canopy
- Emergent trees
Why do plants have thick, waxy leaves with pointed drip-tips? [2]
- Channel rainwater to the point, encouraging runoff so the weight of the water doesn’t damage the plant
- This also means there is no standing water for fungi and bacteria to grow in
How are lianas adapted to the rainforest? [2]
- Climb up trees
- To reach sunlight in the emergent layer
Why do many trees have smooth, thin bark?
Allows water to run off easily
Why do trees have buttress roots?
Provides the support the tall trees need
Why do plants drop their leaves gradually throughout the year?
Enables them to grow all year round
How are spider monkeys adapted? [2]
- Long tail - allows them to swing from tree branches
- Highly developed larynx - allows them to communicate across the treetops
How are geckos adapted? [3]
- Camouflaged - to hide from predators
- Stick toe pads - allows them to grip onto tree trunks and climb vertically
- Detachable tail - allows them to escape predators more easily
How are jaguars adapted? [3]
- Can swim - helps them cross river channels
- Camouflaged - allows them to stalk prey invisibly
- Large claws - allows them to climb trees to catch prey
How does deforestation disrupt tropical rainforest ecosystems? [3]
- Trees stabilise soil with their roots and provide nutrients when they drop their leaves
- With fewer trees, the soil would have less protection from heavy rainfall and the few nutrients left would wash away more easily
- Plants would struggle to grow
How much of the Amazon Rainforest is estimated to be deforested by 2050 at the current rate?
40%
How do tropical rainforests benefit people? [2]
- Products like rubber, coffee, chocolate and medicines sourced from the rainforest
- Sustainable development can offer long-term economic benefits e.g. ecotourism
How do tropical rainforests benefit the environment? [2]
- Protecting the rainforest may reduce the greenhouse effect
- Regulate climate and water cycle
How can tropical rainforests be managed sustainably? [3]
- Replanting trees
- Selective logging
- Ecotourism
What does replanting trees involve?
New trees are planted to replace the ones that were cut down
What does selective logging involve?
Only some trees (e.g. old ones) are felled - most remain