Evolution and Biogeography of Australian Flora Flashcards

1
Q

plants arose from

A

an algae like ancestor

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

bryophytes

A

earliest branching, oldest plants

  • liverworts, mosses, hornworts
  • use spores not seeds
  • lack vascular tissue (small)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

pteridophyte

A

oldest vascular plants

  • lycophytes, ferns and horsetails
  • use spores but height helps with dispersal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

gymnosperms

A

oldest seed producing plants (naked seeds)

  • pines, conifers
  • pollen and seeds by cones (sexual organs)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

angiosperms

A

most recent and common (enclosed seeds)

  • 90% land plants
  • flowers and fruit aid pollenation
  • sexual selection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

why are there similar species in southern areas?

A

past connections and continental drift

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

australia in Gondwana

A
  • cretaceous and cenozoic: Australia was part of Gondwana (NZ, South America, Africa etc.)
  • Australia left Antarctica 30 mill yr ago
  • isolation and evolution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

eucalypts facts

A

75% of biomass

700 species, most endemic to Australia

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

break up of Gondwana and eucalypts

A

160mya

  • Australia, Antarctica, South America and NZ were connected
  • eucalyptus ancestors in wet rainforests
  • eucalyptus pollen 100-66mya (cretaceous)
  • monsoonal (not many fossils) climate, volcanic activity and bushfires - oils make fires easy to start but hard to maintain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

where did eucalyptus go in NZ, South America etc.

A
  • need fire to regenerate
  • wet conditions = fungi, bacteria, disease
  • too wet in NZ
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

arrival of humans

A

arrived 50 000 years ago from Indonesia and china
charcoal evidence suggests earlier
extinctions

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

terrestrial environments

A

tropical, subtropical, temperate, warm temperate

  • great divide - wetter on the East (rainforests) and frier on the west (dry woodland)
  • deserts in central australia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

El Nino - Southern Oscillation

A

2-3 year cycle
usually warm aid goes west to east (cools and descends) high pressure zone
air in the east warms during EN and low pressure in east - drought and bushfire

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

la nina

A

above average rainfall and flooding

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

el nino and la niña are enhanced by

A

climate change

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

marine environments

A

pacific, southern and Indian oceans

latitude and structure of continental shelf affects environments

17
Q

relic and major components of Australian flora

A

relic live in moist, rainforests

major has adapted to arid conditions

18
Q

dominance of hard leaves

A

sclerophylls

  • survive with low nutrients, water stress and fires
  • short leaves, thick cuticle and sunken stomata
19
Q

succulents

A
  • store water in leaves and stems
  • xerophytes (live in dry conditions)
  • sunken stomata
20
Q

myrtaceae

A

eucalyptus family. 4-5 perianth parts and numerous stamens

21
Q

proteaceae

A

banks family - 4 lobed perianth, 4 stamen

22
Q

ericaceae

A

heath family - stiff leaves and tube like flowers, infertile soils

23
Q

mimosaceae

A

wattles - 1000 species, increase nitrogen content of soils

24
Q

fabaceae

A

pea family

25
Q

asteraceae

A

daisy family

26
Q

orchidaceae

A

orchids

27
Q

northern plants

A

migration of plants from elsewhere into the north

seeds in tufts or hairs disperse

28
Q

how to flowers spread pollen

A

attracting animals to flowers and fruit

29
Q

stamen

A

male reproductive parts

filament: holds anther away from flower for pollinators to access
anther: contains pollen grains (each has two sperm cells)

30
Q

sepal

A

modified leaves that surround the bud. make up perianth that envelops the reproductive parts

31
Q

petals

A

modified leaves that also make up perianth

- colours attract pollinators

32
Q

pistil

A

female reproductive part. pollen lands on the sigma and germinates, sending a pollen tube containing sperm down the style. pollen tube delivers sperm to the ovary (egg in an ovule)

33
Q

inflorescence

A

arrangement of flowers like with banksia
can support birds
lots of nectar

34
Q

indigenous use of plants

A
medicine 
insect repellent 
dye 
transport fire
have multiple uses