Colonisation of Land

Question 1

5 requirements for land plant

Answer 1

• Multicellular
• Eukaryotic
• Autotrophic
• Cell wall characterized by cellulose
• Chloroplast with chlorophyll a and b

Question 2

4 shared feature between charophytes and land plants

Answer 2

• Biochemistry
• Cytokinesis
• Sperm ultrastructure
• Cell wall composition

Question 3

What does close relationship between two groups suggest

Answer 3

Land plants most likely evolved from green algae

Charophyte-like algae are ancestors of land plants

Question 4

What are ancestral traits

Answer 4

Evolutionary origin of plants from ancestral algae

- Traits we see land plants have today that ancestors displayed as well

Question 5

What are derived traits

Answer 5

Adaption to plants to a terrestrial environment

- trais organisms have now but ancestors did not have

Question 6

4 problems faced by land plants

Answer 6

• Desiccation
• Support
• Reproduction & development
• Coping w/environmental fluctuations

Question 7

What are embryophyteds

Answer 7

• Land plants with multicellular embryo that develops within the mother plant

Question 8

What are gametophytes

Answer 8

• Multicellular adult with haploid cells that produce gametes by mitosis

Question 9

What are sporophytes

Answer 9

• Multicellular adult with diploid cells that produce spores by meiosis
• It is a diploid cuhs has 2 copies of each chromosome in each cell

Question 10

Describe 3 derived traits of plants

Answer 10

• Alternation of generation & multicellular embryo develops within mother plant
• Walled spores (with sporopollenin) produced in multicellular sporangia)
• Gametes produced in multicellular gametangia
• Growth of shoots and roots (apical meristem)

Question 11

List 4 other adaptions to life on land

Answer 11

• Waterproof cuticle to prevent water loss
• Stoma :
  Allow exchange of co2 and o2
  Prevent moisture loss
• Vascular tissues:
  Xylem; h2o and minerals up fem roots
  Phloem; distribute sugars etc
• Secondary compounds:
  Protect against herbivores, UV, pathogens

Question 12

What key adaption do bryophytes not have that is present in seedless land plants

Answer 12

No vascular system (i.e. no xylem or phloem) so there is a constraint to take up co2.

Question 13

Name 2 constraints and their result for bryophytes that have no vascular system

Answer 13

• Constrain #1 height:
  No vascular system, no true roots, no true leaves
  Water & nutrients transported by diffusion
• Constraint #2 moist environment
  Flagellated sperm must swim to egg thru film o water
  So must live in moist areas

Question 14

How many species of moss found in BC?

Answer 14

1000

Question 15

What does seedless vascular plants key adaption and 3 pros

Answer 15

Vascular tissue

• Allows for efficient transport of water, nutrients, sugars
• Provides structural support
• Reduces height constrant

Question 16

Why would taller plants be better competitors

Answer 16

Better access to sunlight

Question 17

Name a consequence of vascular system and a constraint of seedless vascular plants

Answer 17

Consequence: Increased vegetation
- Increase photosynthetic activity caused a decreased in atmospheric co2
Constraint: Moist environment
- Flagellated sperm must swim to egg thru film of water

Question 18

Name two key adaptions of gymnosperms aka conifers and ginkgoes

Answer 18

Key adaption: Seed
- New sporophyte embryo protected in seed
- Allows for interruption of lifecycle
Key adaption: Pollen
- Male gametophyte protected by spore coat
- Sperm travels in pollen
- Travel by wind: no need for h2o

Question 19

What are 2 key adaptions of angiosperms aka flowering plants

Answer 19

Key adaption: Flower

• Vector pollination increases reproductive success -> more economical & effective even @ low population density
• Co-evolution of plants & pollinators

Key adaption: Fruit
- Dispersal of seeds by animal movement

Question 20

4 characteristics of fungus

Answer 20

• Multicellular
• Eukaryotic
• Heterotrophic
• Absorptive nutrition

Question 21

How do fungal hyphae and plant root function together

Answer 21

Fungal hyphae absorb h2o and minerals better than plant
Plant exchanges sugars and h2o for nutrients
Fungus called Mycorrhizae