Dr Peddie

Question 1

What was a problem for early land plants regarding nutrients?

Answer 1

Nutrients are in the soil rather than in water around them.

Question 2

What was a problem for early land plants regarding light?

Answer 2

They experienced more damaging light, which previously would’ve reflected off the water.

Question 3

What was a problem for early land plants regarding sperm?

Answer 3

They had motile, swimming sperm which on land had no medium.

Question 4

What was a advantage for early land plants regarding light?

Answer 4

There is no filter on useful light and greater levels are available.

Question 5

What was an advantage for early land plants regarding higher oxygen concentrations?

Answer 5

That meant also higher carbon dioxide concentrations.

Question 6

What could early land plants escape from?

Answer 6

Competition and herbivores.

Question 7

What are rhizoids?

Answer 7

Specialised organs that anchor plants to the ground to ensure they remain in the optimal wet habitat.

Question 8

What is the function of waxy cuticles?

Answer 8

To aid in retention of water.

Question 9

What are charophytes?

Answer 9

The likely ancestor of all land plants.

Question 10

Name the asexual, diploid generation of plant life cycles.

Answer 10

Sporophyte generation

Question 11

Name the sexual, haploid generation of plant life cycles.

Answer 11

Gametophyte generation

Question 12

Early land plants and present day Bryophytes have which phase as the dominant one?

Answer 12

Gametophyte phase

Question 13

What is the evidence that liverworts are the most ancient land plant group?

Answer 13

They are the only land plants that lack stomata and have less efficient pores.

Question 14

What are archegonia?

Answer 14

The female organs in liverworts from which sporophytes grow.

Question 15

In which group does the sporophyte outgrow and often outlive the gametophyte?

Answer 15

Bryophytes

Question 16

In what way do their sporophytes characterise vascular plants?

Answer 16

They are independent for most/all of their lifetimes, allowing for gradual increase in size and complexity.

Question 17

What are sori?

Answer 17

Spores produced on the back of leaflets which ?

Question 18

Well developed vascular systems, xylem which forms wood and phloem which are part of bark are all characteristics of which group?

Answer 18

Gymnosperms

Question 19

What is heterospory?

Answer 19

Where microspores, produced by microsporangia, grow into male gametophytes and megaspores, produced by megasporangia, grow into female gametophytes.

Question 20

In early progymnosperms, what was dispersed instead of spores?

Answer 20

Gametophytes

Question 21

How did male gametophytes become specialised for flight?

Answer 21

Development of pollen grain: Size reduction, sculpting for air resistance and, sometimes, development of wings.

Question 22

How did female gametophytes become specialised for male gametophytes to take flight?

Answer 22

Development of ovule: Size and complexity reduction, total decency on mother and enclosing structures.

Question 23

Give 2 advantages of the development of seeds.

Answer 23

1) Allows production of plants in adverse conditions.

2) Provide a head start in competition.

Question 24

Give 2 disadvantages of the development of seeds.

Answer 24

1) Require more investment.

2) Harder to disperse due to increased size.

Question 25

What was a problem for early land plants regarding temperature?

Answer 25

There was much more temperature variation on land.

Question 25

What was a problem for early land plants regarding oxygen concentration?

Answer 25

Higher O2 concentration meant potential oxidative stress.

Question 26

What was a problem for early land plants regarding sex cells and propagules?

Answer 26

Desiccation

Question 27

What did plants evolve to solve the problems of sex cell desiccation?

Answer 27

Sporopollenin

Question 28

What is calyptra?

Answer 28

A covering that protects spores, which are normally liberated by wind.

Question 29

What is an indusium?

Answer 29

An umbrella that dries up to release spores.

Question 30

Where are sporangia on ferns?

Answer 30

Leaf undersides

Question 31

What are 2 things provided by a mother gymnosperm when an embryo leaves?

Answer 31

Integument for protection and nucleus for food.