Plant Evolution

Question 1

What are the benefits of water living for plants? Why leave?

Answer 1

Water Life:
Supported against gravity
Gametes easily dispersed
No threat of drying out
Land Life:
+More direct sun
+Abundant CO2 for photosynthesis
+Absence of herbivores at the time
-Must conserve water
-Disperse gametes
Withstand gravity

Question 2

What is the Alternation of Generation system in plants?

Answer 2

Haploid gametophyte produces gametes by mitosis.
Gametes fertilize each other and create a sporophyte.
Diploid sporophye produces haploid spores by meiosis

Question 3

What are the four radiations of land plants and their key adaptations?

Answer 3

Nonvascular
+Cuticles/protected embryos
Ferns
+Vascular tissue
Gymnosperms
+Seeds
Angiosperms
+Flowers and fruits

Question 4

Nonvascular plant limits

Answer 4

Lack of vascular tissue/support

Question 5

Fern Limits

Answer 5

Fragile gametophyte stage
Relies on water for dispersal

Question 6

Gymnosperms Limits

Answer 6

Must use lots of pollen in hopes of dispersal