CH30

Question 1

What were the plants’ key adaptations for life on land?

Answer 1

• Seeds
• Pollens
• Microscopic gametophytes, due to appearance of the previous two traits

Question 2

Define

Heterospory

Answer 2

The production of two kinds of spores: megasporangia (female gametophytes) and micro sporangia (male gametophytes)

Question 3

Define

Integument

Answer 3

Layer of sporophyte tissue that protects the megasporangium

Question 4

Define

Ovule

Answer 4

Whole structure of megasporangium (2n), megaspore (n) and integument (2n)

Question 5

Define

Pollen grain

Answer 5

Male gametophyte enclosed within pollen wall, latter of which is composed of molecules secreted by sporophyte cells

Question 6

Define

Pollination

Answer 6

Transfer of pollen to part of seed plant that contains the ovules

Question 7

What are the clades of gymnosperms?

Answer 7

1. Ginkgophyta (only ginkgo biloba, is tolerant to stressful conditions)
2. Cycadophyta (palmlike leaves; endangered)
3. Gnetophytes
4. Coniferophyta (most are evergreens)

Question 8

What are the reproductive adaptations of angiosperms?

Answer 8

• Flowers
• Fruits
• Double fertilization

Question 9

Describe

Flowers

Answer 9

• Sepals: enclose flower
• M-Stamens: produce microspores that become pollen grains; composed of filament + anther, where the production occurs
• F-Carpels: makes megaspores; sticky stigma to receive pollen; style; ovary at base
• Petals: attract pollinators

Question 10

Describe

Fruits

Answer 10

• Ovary walls thicken and matures into fruit
• Aid in seed dispersal, as the seeds are protected and transported by animals

Question 11

Describe

Double fertilization

Answer 11

• Two sperm cells unite with two cells in female gametophyte
• One sperm + ovum = zygote
• One sperm + 2 nuclei = endosperm (3n)

Question 12

Describe

Cross-pollination

Answer 12

• Transfer of pollen from anther of flower to anther of flower, both from different plants
• Enhance gentic variability

Opposite of autopollination