Exam

Question 1

What is biodiversity?

Answer 1

The variety of all life in the world, plants animals and micro organisms, the genetic information they contain and the ecosystems they form.

Question 2

Levels of Biodiversity?

Answer 2

Genetic diversity - The variety of genes within a species.

Organismal diversity - The variety of species within a habitat or region.

Ecological diversity - The variety of ecosystems within a given place.

Question 3

What are the patterns of biodiversity and what explains these patterns?

Answer 3

Species vary globally - different yet ecologically similar, animal species inhabit separate, but ecologically similar, habitats around the globe.

Species vary locally - different yet related, animal species often occupy different habitats within a local area.

Species vary over time - some fossils of extinct animals were similar to living species.

Question 4

What are the taxonomic groups?

Answer 4

Bacteria
Viruses
Kingdom Protista
Fungi
Kingdom Plantae
Sponges
Cnidarians
Platyhelminthes
Annelids
Molluscs
Arthropods
Hexapoda - Entognatha, insecta
Echinodermata
Chordata
Chonodrichthyes
Osteichthyes
Amphibia
Reptilia
Aves 
Mammalia

Question 5

What are the six factors identified as primary causes of variation in species richness.

Answer 5

Evolutionary speed
Geographical area
Inter specific interactions
Ambient energy
Productivity
Disturbance

Question 6

Causes of extinction, and ways to conserve biodiversity?

Answer 6

Demographic factors
Industry and urban development
Agriculture
Land use factors 
Grazing by feral and native animals
Other human activities. 

Biodiversity can be preserved in a number of ways including

Question 7

What methods (direct vs. indirect) can we use to survey biodiversity?

Answer 7

Direct sampling - When the sample units are the actual members of the population. Eg: trapping and marking.
Indirect sampling - Sampling from documents or some record of the characteristics of a population, rather than recording of information obtained at first hand from units of the population themselves.

Survey - a study that collects information from a sample of individuals.
Census - a study which aims to collect data from every member of a population.

Question 8

What types of information can we collect (index, census ect.)?

Answer 8

Morphology
Physiology
Abundance
Location

Question 9

What are major threats to biodiversity?

Answer 9

Climate change
Deforestation and habitat loss
Over exploitation
Invasive species
Pollution

Question 10

What is a press disturbance (threat)?

Answer 10

A gradual or cumulative pressure on a system

Question 11

Ecosystem services ($)

Answer 11

Refers to a function humans rely on.

Question 12

How might we conserve biodiversity?

Answer 12

Taxa/taxon based approach -
Threat based approach -
Spatially based approach -
Policy based approach -

Question 13

Bacteria

Answer 13

Generally single cells with simple shapes

Prokaryotes - do not have membrane organelles within the cell, such as nucleus and mitochondria

A quite different life form to plants and animals
0.4 to 5 microns long

Question 14

Viruses

Answer 14

Sub-cellular organisms

Only reproduce in the cells of their hosts

Many cause diseases in plants and animals

Each virus infects a particular host species

Question 15

Kingdom Protista - Protists

Answer 15

Eukaryotes- cells contain several membrane lined compartments

Taxonomy not clear, kingdom Protista thought polyphyletic, ie. numerous evolutionary origins

Most are single called and live in aquatic environments

At least 100,000 species

Question 16

Characteristics of Fungi

Answer 16

Most fungi grow as filamentous hyphae, microscopic filaments with tough waterproof cell walls

Body of the fungus consists of a mass of hyphae - a mycelium

Fungi reproduce by producing spores, single cells for multi celled structures adapted for dispersion and survival

Question 17

Characteristics of Fungi continued

Answer 17

don’t photosynthesise, obtain energy from organic matter

• primary decomposers of organic matter
• secrete enzymes and other substances to assist with external digestion
• saprophytes – live on dead organic matter (e.g. rotting wood, leaf litter – important role in nutrient cycling)
• parasites – live on other living organisms
• mutualists – live in partnership with other organisms

Question 18

Characteristics of plants

Answer 18

plants are everywhere and a part of everyday life

• critical contributions to human wellbeing – food, shelter, aesthetic pleasure
• photosynthetic organisms - (convert light energy to chemical energy and biomass)- ~1/5 of all living organisms able to create energy and provide energy for others using light (CO2 and H2O is pretty damn funky!)
• we use ~1/4 of all global net primary production!
• all land plants are multi-cellular and their cells have specialised to form different types of tissues and organs

Question 19

Sponges (Phylum Porifera)

Answer 19

aquatic animals

• mostly marine
• ~5000 species
• only animal in which cells not organised into tissues or organs
• no mouth, gut, circulatory or nervous system

Question 20

Characteristics of animals

Answer 20

multi-cellular - differentiation into tissues and organs for different functions

• embryonic development - individual develops from single-celled zygote
• heterotrophs - feed on other organisms
• mobile - during at least some stage of life cycle

Question 21

Cnidarians (Phylum Cnidaria)

Answer 21

includes sea wasps, jellyfish, sea anemones, hydrozoans and corals

Two main forms:

•polyp and medusae stages

• polyps (attached, tubular, mouth upward)
• medusae (free floating, mouth downward)
• radially symmetrical
• marine and freshwater

Question 22

Types of Cnidarians

Answer 22

Scyphozoa(jellyfish)
- main life-cycle phase is the floating medusae (jellyfish)

•Cubozoa(box jellyfish)
- includes the sea wasp – stings can be fatal to humans

• Hydrozoa - mostly occur as polyps living colonially
• Anthozoa- sea anemones, corals