Week 7 and 8: Evolution and Biogeography of the Australian Flora

Question 1

What are angiosperms?

Answer 1

Angiosperms are plants that bear their seeds in fruit

Question 2

What % of land plants are angiosperm species?

Answer 2

90%

Question 3

What differentiates angiosperms from gymnosperms?

Answer 3

Both have seeds and pollen but angiosperms bear flowers/fruit

Question 4

What are bryophytes and what are they characterised by?

Answer 4

The oldest plant form - includes mosses

Defined by absence of seeds (uses spores) and vascular tissue (xylem and phloem)

Question 5

Why do bryophytes not grow larger than ~50cm tall?

Answer 5

Lack of vascular tissue limits vertical height

Question 6

What are pteridophytes and what are they characterised by?

Answer 6

Pteridophytes are the oldest form of vascular plants and include fern plants. They do not have seeds but use spores like bryophytes but grow larger as they have vascular tissue

Question 7

Describe some of the qualities possessed by sclerophyll’s

Answer 7

• Thick cuticle
• Short internodes
• Small leaves
• Sunken stomata

Question 8

Sclerophyll’s and succulents are of which family?

Answer 8

Xerophytes - plants that live in dry conditions

Question 9

What type of plant opposes xerophytes?

Answer 9

Mesophytes - plants that live in wet environments

Question 10

List the 5 geographical classification groups of Australian fauna

Answer 10

1. Pangean
2. Gondwanan (Australia, South America, Africa, India, Antarctica)
3. Old Immigrants
4. New endemics
5. Human introduced

Question 11

1. Pangean

Answer 11

Animals have inhabited Australia since the formation and separation of Pangea

Question 12

2. Gondwanan

Answer 12

Animals originated and diversified when Gondwana was still joined. Some animals are present only on some Gondwanan continents e.g. South America and Australia whilst some are present only on others (Africa for example)

Question 13

3. Old immigrants

Answer 13

Flew or rafted from south east Asia to Australia when Australia was not connected to any other land masses

Question 14

4. New endemics

Answer 14

Arrived in Australia when Australia moved closer to south east Asia

Question 15

5. Human introduced

Answer 15

Animals were deliberately or accidentally introduced to Australia by human activity

Question 16

In which Gondwanan continents are marsupial fossils found and not found?

Answer 16

They are found in both Australia and South America but not Africa