Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ecology > Lecture 11 - DA > Flashcards

Lecture 11 - DA Flashcards

1
Q

Define autotroph.

A

Organisms using CO2 as a source of carbon.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define heterotroph.

A

Organisms that use organic carbon as a source of carbon.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name and explain the two kinds of autotrophs.

A

Photoautotroph - Uses light to fix CO2 into organic carbon.

Chemoautolithotroph - obtains energy from the oxidation of inorganic compounds.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What % of Earths surface is covered by water?

A

71

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are coccoliths, and which organisms have them?

A

Calcareous plates of calcium carbonate surrounding some phytoplankton.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define nitrogen fixation.

A

Conversion of N2 gas to ammonia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is ammonium integrated into organic carbon?

A

Assimilation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define nitrification.

A

Conversion of ammonium to nitrates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Can nitrates be converted back to N2 gas?

A

Denitrification.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where is primary production highest in the ocean? Why?

A

Close to the shore, due to runoff from rivers bringing nutrients.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where does nitrogen fixation normally occur in the ocean, and by what?

A

In the middle of the ocean, by cyanobacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is nitrogen fixation typically limited by, and why?

A

May have phosphorus limitations, and is an energy expensive process.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why would bacteria do nitrification?

A

Generates energy for them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which bacteria do nitrification, and is it a rapid process?

A

Betaproteobacteria, and is a very slow process as they grow slowly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Are nitrites/nitrates useful to the bacteria that make them?

A

No, its waste.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define denitrification.

A

Anaerobic reduction of nitrate to N2 gas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the terrestrial nitrogen cycle.

A

Fungi or bacteria live on plant roots, providing nitrate/phosphate to the plant, and getting organic carbon in return.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the phosphorus cycle.

A

Organic phosphorus mineralised by phosphatases into inorganic phosphorus by bacteria and fungi.
Phosphatase is extracellular, so Pi can be taken in by roots/mycelium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Do plants use organic or inorganic phosphorus?

A

Inorganic only.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How many key processes are involved in nitrogen cycling?

A

6.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the sulphur cycle.

A

Sulphur is present in the soil in esters and amino acids.

Converted to sulphates by bacteria so plants can use it.

22
Q

Give the common name for the following:
Protheria
Metatheria
Eutheria

A

Protheria - monotremes
Metatheria - marsupials
Eutheria - placentals

23
Q

What are 2 common monotremes? Do they lay eggs?

A

Echidna, and platypus. Lay eggs.

24
Q

Where are monotremes found?

A

Only in Australia.

25
Q

Name some common marsupials.

A

Bandicoots, taz devil, wombats, koalas, kangaroos, wallabies.

26
Q

Name some placentals.

A

Rats/mice, bats.

27
Q

Out of the monotremes, marsupials, and placentals, which was first to inhabit Australia?

A

Monotremes.

28
Q

How did marsupials reach Australia, and from where? What about placentals?

A

Started in China, to NA, then SA, to Antarctica, then Australia.
Placentals are similar, but only flying ones reached Australia.

29
Q

Do any organisms living in the desert cope with the heat, or try to avoid it instead?

A

All animals avoid the heat regardless of size or diet, tend to be nocturnal.

30
Q

What factor is a driving force for habitat selection and distribution in Australia, especially deserts?

A

Water.

31
Q

Do animals tend to avoid heat during the day in grasslands?

A

Yes.

32
Q

Is free water found in grasslands?

A

Yes, in some areas.

33
Q

Are open forests cooler than grasslands?

A

Yes, due to more vegetation cover and water.

34
Q

How are species distributed in open forests?

A

By strata - their height, composition, and nutrient availability.

35
Q

Is the climate constant in rainforests?

A

Yes.

36
Q

Is water freely available in rainforests?

A

Yes.

37
Q

Are rainforests good shelter for animals?

A

Yes, but too dense for large animals.

38
Q

Do alpine regions have low or high seasonal variation in temperature?

A

High.

39
Q

What provides protection in alpine regions during winter?

A

Rock cover, and burrowing into soil.

40
Q

Do alpine animals seek cover during seasonal changes?

A

Yes, but some can migrate with seasons to better cope.

41
Q

Is water scarce during summer in alpine regions?

A

Yes.

42
Q

Which native Australian mammal is distributed across the continent?

A

Echidna.

43
Q

Do echidna have a particular habitat requirement?

A

No.

44
Q

How do echidna cope in alpine regions during winter?

A

Hibernate.

45
Q

What are megafauna, and where are they now?

A

Huge car sized mammals before indigenous population came. They were hunted by them, and predated by dingoes which were introduced by aborigines. Now extinct.

46
Q

What 2 reasons led to the extinction of the taz tiger?

A

Dingo predation and human culling.

47
Q

What is the habitat requirements of the leadbeater possum like, and what are they threatened by?

A

Very specific requirements, threatened by wildfires and timber industry.

48
Q

Where are mountain pygmy possums found, and what is leading their numbers to drop?

A

Alpine regions.

Habitat loss from ski fields, wildfires, and predation by feral cats and foxes.

49
Q

Which population of taz devils does devil facial tumour disease affect?

A

Only those in Tasmania.

50
Q

What is leading to a drop in numbers of taz devils?

A

Devil facial tumour disease
Road, dog and fox kills
Low genetic diversity

51
Q

What 3 factors are leading to a drop in numbers of eastern barred bandicoots?

A

Habitat destruction from introduced herbivores, predation, and disease.

Ecology (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions