Module 3

Question 1

What is biodiversity

Answer 1

Range of organisms that make up the living world. Includes the genes that create organisms. All the systems are interrelated and connected into one.

Question 2

Genetic diversity

Answer 2

• Variety of genes within a species.

- Each species is made up of individuals that have their own particular genetic composition.

Question 3

Species diversity

Answer 3

• Some habitats, such as rainforests and coral reefs, have many species. Others, such as salt flats or a polluted stream, have fewer.
• Species are grouped together into families according to shared characteristics

Question 4

Ecosystem diversity

Answer 4

• The variety of ecosystems in a given place

- An ecosystem is a community of organisms and their physical environment interacting together.

Question 5

Megadiversity

Answer 5

• Megadiversity describes countries with very high levels of biodiversity.
• Twelve of the megadiverse countries, including Australia, contain about 75% of Earth’s total biodiversity.

Question 6

Gondwanan diversity

Answer 6

• Australia was once part of the great southern supercontinent Gondwana
• Australia’s unique biodiversity and our high number of endemic species (that is, they only occur naturally in Australia) is mostly explained by the isolation of our continent from other land masses.

Question 7

How to conserve biodiversity

Answer 7

save habitats and ecosystems rather than trying to save a single species.

Question 8

Human impact on biodiversity

Answer 8

• Destruction and fragmentation of habitats  farming, logging, fishing, urbanisation
• Exploitation of species  fishing and logging
• Pollution  factories, manufacturing
• Introduction of alien species  disease and parasites, habitat alteration, competition, interbreeding
• Climate change  burning fossil fuels

Question 9

Abiotic factors

Answer 9

These are non-biotic or non-living.

Eg. Climate, light, temperature, wind speed, sunshine, water, altitude.

Question 10

Biotic factors

Answer 10

These are the biotic or living.

E.g. sources of food, number of predators etc. competition between species or within species,

Question 11

What do Abiotic and Biotic factors determine

Answer 11

The distribution of organisms – where organisms are found in the ecosystem

The diversity of organisms – the different type of organisms

The abundance of organisms – how many organisms are present

Question 12

Trophic cascade

Answer 12

an ecological process that starts at the top of the food chain.

Question 13

Wolves trophic cascade

Answer 13

Wolves change rivers: changed behavior of deer’s from grazing vegetation, less erosion of rivers and more pools formed. Regenerating the forests stabilised the river banks too.

Question 14

Whales trophic cascade

Answer 14

Whales changing climate: Mixing effect  return nutrients and plankton to surface which photosynthesis carbon dioxide and transfer it from the air to the bottom of the ocean - changes climate

Question 15

Structural adaptation with example

Answer 15

relates to size and shape of an organism and its body parts - Kangaroos have powerful leg muscles

Question 16

Physiological adaptation with example

Answer 16

relates to how an organisms body functions - Camouflage

, Humans sweat to assist heat loss

Question 17

Behavioural adaptation with example

Answer 17

actions that an organism takes to improve survival or reproduction
○ Penguins huddle to stay warm.

Question 18

Natural selection

Answer 18

process by which organisms that are best suited to their organism survive and reproduce, passing on their favourable traits.

Question 19

Steps of natural selection

Answer 19

Variation  Selective reproduction  inheritance  gradual change in population

Question 20

Peppered moth

Answer 20

1. In moth population there was variation in colour (some light, some dark)
2. The Industrial Revolution put soot on light coloured trees, making dark coloured moths better camouflaged and more likely to live and reproduce (wouldn’t get predated by birds)

Question 21

Galapagos Finches

Answer 21

1. Common cactus = longer, more pointed beak  allows it to probe and open small fruits and extract nectar from flowers, insects from cracks
2. Medium ground finch = shorter, blunter beak  cracking open seeds

Drought (selection pressure) medium ground finch advantage as they were able to eat seeds still.

Question 22

Sexual selection

Answer 22

The traits that increase the likelihood to be chose as a mating partner are more likely to be inherited in offspring, causing gradual change in population.

Question 23

PUNCTUATED EQUILIBRIUM

Answer 23

Describes organisms as undergoing long periods of no change that are ‘punctuated’ by rare episodes of rapid change.