Tropical Rainforests 1

Question 1

What is biodiversity?

Answer 1

The variety of organisms living in an area.

Question 2

Is biodiversity high in hot deserts? Why/why not?

Answer 2

Yes. Temperatures and precipitation are high all year round - this climate provides the perfect growing conditions for plants.

Question 3

Name the layers of the rainforest.

Answer 3

-The Forest floor (shrub layer)
-The Undercanopy
-The canopy
-The emergent layer

Question 4

Describe the emergent layer.

Answer 4

-Contains emergent trees (up to 200ft tall)

-which only have branches at their crown, where the most light is available

-Homes birds and insects

Question 5

Describe the canopy layer.

Answer 5

-The primary layer of the rainforest as life is most abundant here

-Receives a lot of light, so foliage cover is dense

-High biodiversity(insects, birds, reptiles, mammals, and a variety of plant life).

Question 6

Describe the undercanopy layer

Answer 6

-A cool and dark environment with high humidity so therefore a high concentration of insects

-Some plants have large leaves to absorb as much light as possible, whereas some focus their energy on growing upward towards the light as there is so much competition

Question 7

Describe the forest floor (shrub) layer.

Answer 7

-Very little light, hence foliage not very dense

-Home to the largest animals that live in the rainforest

-Teeming with insects as they like the dark and damp conditions

-Very poor soils

Question 8

Why are rainforest soils infertile?

Answer 8

-There are high levels of rainfall and the rain leeches away nutrients from the top soil and rich leaf litter

-Plants uptake nutrients from decomposing organic matter very quickly

Question 9

What are plants in the rainforest adapted to?

Answer 9

High rainfall, high temperatures, and little light.

Question 10

What are animals in the rainforest adapted to?

Answer 10

Finding food and escaping predators.

Question 11

Epiphytes

Answer 11

-Start growth in the canopy layer, gaining nutrients from moss, and water from the humid air (they hang their roots off other branches)

-This means that they do not start growth on the forest floor in competition with many other plants for the little light available

-Which means they have a ‘head start’ and are more likely to survive.

Question 12

Climbing plants

Answer 12

-Climbing plants such as lianas grow around other trees trunks

-This means that they won’t waste energy growing wide to support themself

-Which means they can instead focus on growing upwards towards the sunlight.

Question 13

How are plants in the forest floor layer adapted?

Answer 13

-Plants in the forest floor layer often have very broad leaves to absorb as much light as possible

-This means that they have drip tips to allow water to run off the leaves, preventing rot.

-Leaf surfaces are also waxy to prevent water runoff, discouraging rot and the growth of bacteria and fungi

Question 14

Why do most rainforest animals spend the majority of their lives in the canopy layer?

Answer 14

-It has the highest biodiversity, therefore is the best place to find food (applies to both produces and consumers)

-It’s also safe from large predators on the forest floor such as jaguars.

Question 15

How are parrots adapted to living in tropical rainforests?

Answer 15

-Large powerful beaks to easily crack open nuts and seeds

-Short elliptical wings ideal for fast, agile flight and easy manoeuvring between the dense canopy of trees

-Waterproof wings to fly in rainy conditions, allowing them to escape predators

Question 16

How are sloths adapted to living in tropical rainforests?

Answer 16

Their anatomy is adapted to support a hanging lifestyle:

-Strong limbs
-Long, curved claws that provide a powerful grip to hang and stay hanging (e.g. when hunted)

-Slow moving to conserve energy (so much so that algae grows on their fur providing camouflage)
-Nocturnal - feed at night when it’s cooler to conserve energy

Question 17

Why is it important to protect tropical rainforests?

Answer 17

-They are home to more than 50% of all plant and animal species on Earth

-many of these species are endemic to the rainforest

-This means that uncontrolled deforestation and development of rainforests is likely to lead to the extinction of many species, which would mean a huge loss of biodiversity.

Question 18

Why are tropical rainforests valuable to people?

Answer 18

-Many products (e.g. rubber, coffee, medicines) are sourced from the rainforest

-Sustainable development can offer long term economic benefits, e.g. ecotourism

Question 19

What is the effect of species becoming extinct?

Answer 19

-if species become extinct, it’s harder to discover new medicines and develop new products.

-loss of biodiversity

Question 20

How are tropical rainforests valuable to the environment?

Answer 20

-The trees act as a carbon sink, so protecting the rainforests may reduce the greenhouse effect by reducing CO₂ emissions (from burning etc.) and allowing the trees to continue absorbing CO₂

-Rainforests help regulate the climate and water cycle - without them the risks of drought and flooding in certain areas can increase.

Question 21

Rainforest water cycle:

Answer 21

Trees intercept and take up lots of water from the soil, releasing it back into the atmosphere providing more water for future rainfall.

This also prevents the rainwater leeching away nutrients from the top soil layer.

Question 22

How does deforestation affect the rainforest water cycle?

Answer 22

Trees take up water and release it back into the atmosphere.

Reducing tree cover may increase the risk of drought , affecting the plants and animals who live in the rainforest ecosystem and are not adapted to dry conditions.

Question 23

Describe the climate of tropical rainforests.

Answer 23

The climate is the same all year round, with no definite seasons. Temperature and rainfall are constantly high (20-28°C and around 2000mm of rainfall per year).

This is because the sun’s energy is overhead and intense at the equator.

Question 24

Describe the interdependence of climate in tropical rainforests.

Answer 24

The warm and wet climate helps fungi and bacteria to decompose dead material rapidly.

This means that the top layer of soil is nutrient rich, which means that plants can uptake the nutrients and grow quickly
(nutrient cycling is quick)

Question 25

Describe the interdependence of plants in tropical rainforests.

Answer 25

-Plants uptake nutrients from the soil rapidly

-They pass on their nutrients when eaten by animals

-As the vegetation is dense it provides a lot of food, so animal populations are high.

Question 26

Describe the interdependence of animals in tropical rainforests.

Answer 26

-As the vegetation is dense it provides a lot of food, so animal populations are high.

-When these animals die, they first become a part of the litter layer, and then the dead material is broken down by decomposers, transferring their nutrients back to the top layer of soil.

-Nutrient-rich soil helps plant to grow, so the cycle repeats.

Question 27

Why is nutrient cycling so quick in tropical (rainforest) conditions?

Answer 27

The warm and wet climate allows bacteria and fungi to decompose dead material quickly.

Question 28

Symbiotic relationship

Answer 28

Where plant and animal species depend on each other for survival.

Many plants and animals in tropical rainforests have formed this kind of relationship for example, agouti and walnut trees.