Topic 16

Question 1

Shared Derived Traits of seed plants

Answer 1

1. Reduce gametophytes
2. Heterospory of microsporangia and megasporangia. Spores are not dispersed
3. Ovules
4. Pollen
5. Seeds

Question 2

Female Gametophyte in Seed Plants

Answer 2

The megasporangium (2n) produces a megaspore (1n) via meiosis enclosed in protective integuments (2n).

The megaspore is not dispersed, but pollination triggers female gametophyte developement

Question 3

Pollen

Answer 3

Pollen grains hold microspores that develop into male gametophytes

Question 4

Male Gametophyte

Answer 4

Microsporangium (2n) produces microspores (1n) via meiosis.

This is not dispersed, but develops into pollen grains

Question 5

Pollination

Answer 5

Transporting pollen into the ovule for fertilization, which eliminates the need for water during fertilization

Question 6

Evolutionary Advantages of Seeds over Spores

Answer 6

1. Seed plants evolved structures to enhance long-distance seed dispersal
2. Seeds have external coats to protect the embryo
3. Seeds have energy-dense supply of stored food that supports early seedling growth

Question 7

Two Clades of Seed Plants

Answer 7

Gymnosperms and Angiospersm

Question 8

4 Phyla of Gymnosperms

Answer 8

1. Cycadophyta (Cycads)
2. Ginkophyta
3. Gnetophyta
4. Coniferophyta

Do NOT form a monophyletic group

Question 9

Key Features of Life Cycle of Gymnosperms

Answer 9

1. Gymnosperms have dominant sporophyte generations
2. Gymnosperms develop seeds from fertilized ovules
3. Transfer of male gametophytes to ovules by pollen