Biodiversity

Explain the meanings of ecosystem and niche.

Feb/March 2017

Explain what the term biodiversity means.

Feb/March 2019

The text in Fig. 10.1 is about biodiversity. Fill in the gaps with the most suitable scientific terms.

Feb/March 2023

The plant Rafflesia arnoldii, which is found in the rainforests of South East Asia, is famous for having the largest flower of any plant. Its flower is reddish-brown and can reach a diameter of one metre. It releases an odour like decaying flesh to draw in flies, and these flies then pollinate it. Fig. 6.1 shows a flower of R. arnoldii.

May/June 2012

Sarawak lies in south-east Asia, and much of it is covered by tropical rainforest. Logging was permitted across extensive parts of the forest. A study was conducted to estimate the population size of several mammal species living in the rainforest: • prior to logging • straight after logging • two years later • four years later. Table 8.1 gives the findings for six mammal species. If the numbers were too low for population density to be measured, the species were recorded as "present". Mean number of animals per $\text{km}^{-2}$.

May/June 2013

Fig. 5.1 depicts a raccoon, Procyon lotor. This species originates in North America. Four individuals were released in Germany in 1934. It is now believed that Germany has more than a million raccoons.

May/June 2016

Ecosystems across North America show a large degree of variation. Examples include coniferous forest, prairie grassland, scrub and desert. Extensive areas that formerly supported natural ecosystems are now devoted to agriculture.

May/June 2017

An investigation was done in a temperate woodland that included several areas with two distinct kinds of ground-cover vegetation. • On higher ground, where the soil was drier, the main ground-cover plant was bracken, $\textit{Pteridium aquilinum}$. • On lower ground, where the soil was wetter, the main ground-cover plant was bramble, $\textit{Rubus fruticosus}$.

May/June 2017

North America contains a very wide range of ecosystems, so the continent shows marked variation. These ecosystems include coniferous forest, prairie grassland, scrub and desert. A great deal of land that formerly supported natural ecosystems is now used for agriculture.

May/June 2017

Table 8.1 compares the total counts of plant species, insect species and habitats found in the three areas, A, B and C.

May/June 2019

What is meant by the term ecosystem?

May/June 2019

The passage below describes one technique a student used to estimate the population size of an animal species. Fill in the gaps using the most appropriate scientific term or terms.

May/June 2019

Sampling can be used to discover how many different species are present in an ecosystem and to estimate the population size of each species. A study was done to examine the biodiversity of two fields, A and B. Field A had not been used to grow crops for 10 years. Field B had been used to grow crops until one year before the study began. Random sampling was carried out.

May/June 2020

Over the last 200 years, many animal and plant species have become extinct. Fig. 8.1 shows how, from 1800 to 2000, the number of species going extinct and the size of the world human population changed.

May/June 2022

During the 1780s, the normal ecosystem on Hawadax Island in Alaska was thrown off balance when brown rats, Rattus norvegicus, swam ashore from a sinking ship and then their population expanded rapidly. On the island, the rats occupied a new niche as predators. They consumed the eggs and chicks of birds including the black oystercatcher, Haematopus bachmani, and the glaucous-winged gull, Larus glaucescens. These birds nest, lay eggs and raise their chicks on the island beaches.

May/June 2023

Outline how a frame quadrat could be used to assess plant biodiversity in a field.

May/June 2025

The golden poison dart frog, $\textit{Phyllobates terribilis}$, occurs in the Colombian rainforest ecosystem. Fig. 10.1 depicts golden poison dart frogs.

May/June 2025

The Great Lakes in North America are situated between the USA and Canada. A survey of birds in the Lake Ontario region has revealed how the relative abundance of birds changed from 1995 to 2005. Table 1.1 lists the feeding habits and the relative change in the numbers of some of the birds in the survey.

Oct/Nov 2010

In North America, the Great Lakes sit between the USA and Canada. A survey of birds in the Lake Ontario area has recorded the relative abundance of birds between 1995 and 2005. Table 1.1 gives the feeding habits and the relative change in numbers of some of the birds in the survey.

Oct/Nov 2010

A $50$-year survey of marine animal biodiversity in Canada's coastal waters was carried out. The percentage fall in the number of marine animal species between $1950$ and $2000$ is shown in Fig. 1.1.

Oct/Nov 2010

Explain what biodiversity means.

Oct/Nov 2015

Italy's land area includes forest, grassland (such as agricultural fields), built-up land such as towns and cities, and inland water bodies such as lakes and rivers. Table 5.1 presents how the area occupied by these environments changed across a fifteen year period.

Oct/Nov 2016

Italy's land area is made up of forest, grasslands (including agricultural fields), built-up regions (for example towns and cities), and inland water bodies such as lakes and rivers. Table 5.1 presents the changes in the area covered by these environments over a fifteen-year period.

Oct/Nov 2016

To measure insect biodiversity on Acacia trees in the African savannah, the researchers used this procedure: insecticide was sprayed into every tree; the insects were killed and dropped onto a sheet placed underneath the tree; the dead insects were then gathered, identified and counted.

Oct/Nov 2016

In Canada, the St. Lawrence river has been recognised as an area of exceptionally high biodiversity.

Oct/Nov 2017

In Canada, the St. Lawrence river has been identified as an area with exceptionally high biodiversity.

Oct/Nov 2017

Palm oil is a vegetable oil used very extensively in food products. It is obtained by extracting oil from the fruit of the oil palm tree.

Oct/Nov 2020

Describe a way that could be used to estimate the population size of a mobile animal, for example a brown rat.

Oct/Nov 2020

Palm oil is a vegetable oil used in many food products. It is obtained from the fruit of the oil palm tree.

Oct/Nov 2020

Ecological surveys are carried out before conservation choices are taken. For instance, a survey may be completed before deciding if a species should be returned to its former habitat.

Oct/Nov 2021

Biodiversity may be looked at on three separate levels. Fig. 5.1, Fig. 5.2 and Fig. 5.3 are pictures that illustrate these three levels of biodiversity.

Oct/Nov 2021

Ecological surveys are carried out before conservation choices are taken. For instance, they may be done before deciding whether to reintroduce a species into its previous habitat.

Oct/Nov 2021

Biodiversity may be assessed at three separate levels. One of these is the genetic variation found within each species.

Oct/Nov 2023

Biodiversity may be assessed at three separate levels. One of these is the genetic variation within a species.

Oct/Nov 2023

Palm oil is the vegetable oil used most widely. It comes from the African oil palm, Elaeis guineensis. Oil palms are the crop with the greatest yield of vegetable oil, and they need only 10% of the land area that other crops would require to make the same amount of oil. On Borneo, tropical rainforests are felled and cleared so that oil palm plantations can be established. This has a major impact on biodiversity. The Bornean orangutan, Pongo pygmaeus, occurs only on Borneo and is classed as critically endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species™.

Oct/Nov 2025