Question 1

Soil in tree-dominated ecosystems is

Accepted Answer

A)  stabilised by plant roots. 
B)  particularly susceptible to erosion because it has a covering of litter. 
C)  subject to high wind velocity due to vegetation cover. 
D)  susceptible to erosion due to burrowing rabbits. 
E)  typically compacted with slow rates of rainwater absorption. 
A)  stabilised by plant roots. 
B)  particularly susceptible to erosion because it has a covering of litter. 
C)  subject to high wind velocity due to vegetation cover. 
D)  susceptible to erosion due to burrowing rabbits. 
E)  typically compacted with slow rates of rainwater absorption.

Question 2

In rainforests,

Accepted Answer

A)  gaps created by tree falls and forest fires are insignificant. 
B)  the slash-and-burn agriculture of indigenous Amazonians has the same impact as naturally occurring gaps. 
C)  clearing creates soils capable of supporting productive pasture for very long periods of time. 
D)  there is rapid nutrient recycling back to the living biomass. 
E)  are a very stable ecosystem, maintained by decomposers and bacteria. 
A)  gaps created by tree falls and forest fires are insignificant. 
B)  the slash-and-burn agriculture of indigenous Amazonians has the same impact as naturally occurring gaps. 
C)  clearing creates soils capable of supporting productive pasture for very long periods of time. 
D)  there is rapid nutrient recycling back to the living biomass. 
E)  are a very stable ecosystem, maintained by decomposers and bacteria.

Question 3

Which of the following is NOT a reason to conserve biodiversity?

Accepted Answer

A)  Organisms are essential for ecosystem survival. 
B)  We need many different organisms to maintain or lifestyle. 
C)  Biodiversity provides enjoyment through complexity and aesthetics. 
D)  Each country has its own individual cultural biodiversity. 
E)  From an ethical point of view we should support survival of the fittest. 
A)  Organisms are essential for ecosystem survival. 
B)  We need many different organisms to maintain or lifestyle. 
C)  Biodiversity provides enjoyment through complexity and aesthetics. 
D)  Each country has its own individual cultural biodiversity. 
E)  From an ethical point of view we should support survival of the fittest.

Question 4

Two farmers grow identical crops on adjacent land. One uses a traditional chemical fertiliser regime to maximise his agricultural output, whereas the other uses microorganic bio-fertilisers and crop rotation to minimise his use of chemical fertilisers. The first farmer who uses a traditional chemical fertiliser regime initially has higher yields with less effort, but over time his yields start to drop and continue to do so while the second farmer maintains a consistent output. What might be causing the drop in yield for the first farmer?

Accepted Answer

A)  Soil acidification 
B)  Soil erosion 
C)  Sodic soils 
D)  Soil alkalinity 
E)  Ion toxicity 
A)  Soil acidification 
B)  Soil erosion 
C)  Sodic soils 
D)  Soil alkalinity 
E)  Ion toxicity

Question 5

Frugivorous cassowaries are threatened by rainforest clearing in Queensland. A likely consequence of the disappearance of these birds is that

Accepted Answer

A)  many tree species will not be able to disperse. 
B)  emus will move in to fill the vacant niche. 
C)  the fruits they eat will be available for other animals, so the diversity will change. 
D)  the understory will become denser as grazing pressure declines. 
E)  there will be rapid speciation in other areas. 
A)  many tree species will not be able to disperse. 
B)  emus will move in to fill the vacant niche. 
C)  the fruits they eat will be available for other animals, so the diversity will change. 
D)  the understory will become denser as grazing pressure declines. 
E)  there will be rapid speciation in other areas.

Exam 46: Human Impacts

Soil in tree-dominated ecosystems is

In rainforests,

Which of the following is NOT a reason to conserve biodiversity?

Frugivorous cassowaries are threatened by rainforest clearing in Queensland. A likely consequence of the disappearance of these birds is that

Nature of Molecules

Biomolecules

The Chemistry of Life

Functioning Cells

Movement Across Membranes

Harvesting Energy

Cells, Tissues and Signals

Cell Division

Inheritance

Genes, Chromosomes and Dna

The Genetic Code

Gene Expression

Genomes, Mutation and Cancer

Viruses

Genetic Engineering and Biotechnology

Reproduction, Growth and Development of Flowering Plants

Structure of Plants

Plant Nutrition, Transport and Adaptation to Stress

Plant Hormones and Growth Responses

Animal Reproduction

Animal Development

Homeostasis: Water, Solutes and Excretion

Gas Exchange in Animals

Circulation

Metabolism, Temperature Regulation and Environmental Stress

Animal and Human Nutrition

Innate Defences and the Immune System

Hormonal Control in Animals

Nervous Systems

Animal Movement

Animal Behaviour

Evolving Life

Evolving Earth

Mechanisms of Evolution

Bacteria

The Protists

Plants

Fungi

Simple Animals: Sponges to Flatworms

Annelids, Molluscs, Nematodes and Arthropods

Echinoderms and Chordates

Australian Biota

Population Ecology

Living in Communities

Ecosystems

Filters