Practise IB Biology HL B4.2 by comparing ecological niches and feeding strategies, explaining adaptations, and analysing competition between species.
Outline what is meant by the niche concept.
Marine sediments form at the bottom of oceans. These sediments contain organic material from the surface waters. Scientists analysed samples drilled from the floor of the north Pacific Ocean, representing 86 million years of sedimentation. Graph A shows the data for oxygen concentrations in 28 metres of sediment and graph B shows the oxygen consumption per cell in 22 metres of sediment measured in femtomoles ( ).
Suggest reasons for the differences in oxygen consumption between the cells at 2 metres and at 22 metres.
There is evidence that prokaryotes were responsible for changes in the atmospheric gases 3.5 billion years ago. Outline the role of bacteria in producing an oxygen-rich atmosphere.
Hummingbirds eat flower nectar and small insects. To which nutritional group do they belong?
Autotrophs
Consumers
Detritivores
Saprotrophs
The diagram shows the flow of energy between some Arctic species.
Which organism is a mixotroph?
Bacteria
Nanoflagellates
Micromonas
Copepods
The pie chart shows the modes of nutrition of fungi in Huahu Lake wetland in China.
What is the most common mode of nutrition of fungi in this wetland?
Heterotrophic fungi that feed on living organisms by ingestion
Autotrophic fungi that obtain organic nutrients from detritus by internal digestion
Fungi that have either an autotrophic or heterotrophic method of nutrition
Heterotrophic fungi obtaining nutrients from dead organisms by external digestion
One method used by microbiologists to distinguish between Archaea and Eubacteria is the conditions they need for survival. Both groups include thermophiles, which are species that are adapted to live at high temperatures. The graph shows the optimum temperature and minimum pH required for growth by selected species of Archaea and thermophilic Eubacteria.
State a possible habitat for methanogenic Archaea.
The diagram shows the range of heights and brain sizes found in four groups of hominids.
State two ways, apart from brain volume, by which the skulls of the Australopithecus and H. erectus would differ in appearance.
1.
2.
The photo shows vegetation in the Sonoran Desert, which is part of the hot desert biome.
State one adaptation of plants in hot deserts that can help them to resist herbivory.
One additional mark is available for the construction of your answers for each question.
Butterflies have evolved different methods of defence against bird attacks. The relative escaping ability and unpalatability (distastefulness) of different tropical butterfly families and subfamilies was investigated in the presence of wild kingbirds, Tyrannus melancholicus, a natural predator of butterflies. Each symbol on the graph represents a different species within a (sub)family.
State which butterfly (sub)family contains the species with the greatest escaping ability.
Suggest one feature of butterfly wings that might help a butterfly to escape from a predator.
The graph shows that distasteful butterflies tend to have a lower ability to escape from predators than palatable butterflies. Suggest reasons for this trend.
The model describes the fundamental and realized niches of a species of microscopic marine arthropod in the Northern hemisphere with respect to two different factors ( X and Y ). The abundance of the species is shown over twelve months. The fundamental niche is separated into five zones ranging from critical to optimal conditions. The population of the species in its realized niche each month is represented by an oval. The size of each oval shows the population abundance.
Distinguish between fundamental niche and realized niche.
Outline the principle of competitive exclusion.