Chapter 26 worksheet

1)Compared to seedless plants, seed plants dominate the land and are found in diverse environments. What major adaptation is most likely the cause of this success? Explain.

2) Describe the evolutionary trends of the seed plant in terms of the sporophyte generation, the

gametophyte, and spore production.

3) Differentiate between megaspores and microspores.

4) What two critical adaptations (evolutionary advantages) distinguish seed plants from seedless

plants and allowed them to survive on dry land? Explain how these adaptations bypasses the need

for water and allow for the success of seed plants.

5) What is an ovule? What is a pollen grain?

6. What is a seed? Describe the three major components and the benefits of each.

7. What defines a gymnosperm? What defines an angiosperm? 

8. Based on fossil record, in what period did gymnosperm dominate? When did the angiosperm

surpass the gymnosperm? Which are currently the most abundant plants?

9. Define flower. Define fruit. (Make sure to include the purpose.) What are the evolutionary

advantages of these two structures? In what plant group(s) are they found?

Section 26.2

10. Are gymnosperms monophyletic? Explain.

11. Define sporophyll. Give an example.

12. Define integument.

13. Differentiate between monoecious and dioecious plants.

14. Fill in the following chart:

Division and common name, Defining characteristics + fossil records, Example(s) Flagellated sperm?, Monoecious?, Dioecious?

• Coniferophyta (conifers)
• Gingkophyta
• Cycadophyta
• Gnetophyta

15. Describe the life cycle of a pine tree

Section 26.3

16. Draw a typical flower. Label the major parts (sepals, petals, carpel/pistil, stigma, style, ovary,

filament stamen, anther, receptacle). Make sure to note the male and female reproductive

structures and the purpose of each part.

17. Describe the life cycle of an angiosperm; make note of double fertilization and its two products.

18. What is a cotyledon?

19. Define a perfect flower. Is self-pollination common in perfect flowers? Explain.

20. Why are vegetables such as eggplants and string beans considered fruits?

21. Mature fruits can be classified in two ways. What are these? Give an example of each.

22. Not all fruits originate from just the ovary. From what floral part(s) are the following derived?

(1) Strawberry:

(2) Apple:

(3) Raspberry:

(4) Pineapple:

23. The ultimate purpose of fruits is ___________________________________________________.

24. Differentiate between monocots and dicots by filling in the following chart:

Monocot Dicot (a.k.a. Eudicot)

Number of cotyledon

Venation (vein pattern)

Floral parts

Stem vascular arrangement

Type of root (root system)

Pollen shape

Section 26.4

25. Describe the process of pollination and the role of pollinators.

Chapter 26 worksheet

1. The major adaptation is the independence of water.

2. The sporophyte generation is dominant in the seed plant as compared to the gametophyte, and they are heterosporous.

3. Megaspores - pollen grains,

Microspores - egg cell.

4. he two critical adaptations also referred to as evolutionary advantages that distinguish seed plants from seedless are the adaptations to drought and reproduction without water.

5. Ovule - egg cell bearing organ

Pollen grain - sperms bearing structure.

6. Seed - The progenitor of the new plant.

7. Gymnosperm - non-flowering plants.

Angiosperm - flowering plants.

8. The gymnosperms (non-flowering plants) dominated the land in the Triassic (early) and Jurassic (middle) Mesozoic era.

9. Flower - the reproductive unit of a plant.

Fruit - protects the product of fertilization.

Section 26.2

10. Yes, gymnosperms are monophyletic.

11. Sporophyll - leaf-like structure.

12. Integument - the outer covering of the seed.

13. Monoecious - These plants consist of both male and female reproductive organs on the same plant.

Dioecious - The male and female reproductive organs are present on the separate plant.

14. Coniferophyta - the division of conifers

Gingkophyta - the division of Ginkgo

Cycadophyta - the division of cycads

Gnetophyta - the division of Gnetum

15. Sperms + eggs → zygotes → embryo → seeds → new plant → cones

Section 26.3

16. A typical flower consists of the sepals, petals, carpel/pistil, stigma, style, ovary, filament stamen, anther, and receptacle.

17. Pollen grains (sperms) + Ovary (eggs) → zygotes → embryo → seeds → new plant → flowers.

18. Cotyledon - embryonic leaf

19. A perfect flower - carpel and stamen on the same flower.

20. The fruit bears the seeds.

21. Simple and aggregate fruits.

22. (1) Strawberry: receptacle

(2) Apple: thalamus

(3) Raspberry: several carpels

(4) Pineapple: several flowers

23. Seed protection.

24. Monocots - single cotyledon

Dicots - double cotyledon

Section 26.4

25. Pollination - The transfer of pollen grains to the stigma of the flowers. 

Step-by-step explanation

Chapter 26 worksheet

1. The major adaptation that is most likely the cause of domination of the seed plants on the land as compared to seed plants are:

The storage tissue present in the seeds of the seed plants helps to sustain growth.

The several layers of a protective coat of hardened tissue help to avoid desiccation and other harsh conditions.

The protective coating also frees the process of reproduction from the requirement for the constant water supply.

Although the seedless plants transitioned from the aquatic to terrestrial habitat, they are not completely independent of water and had to develop tactics to avoid drying out. While seed plants have adaptations allowing them to populate in the aridest habitats.

Most of the seedless plants still need a moist environment for pollen and seed dispersal.

2. The evolutionary trend in seed plants directed to the dominant sporophyte generation and simultaneously, an orderly reduction in the gametophyte size. The gametophyte changed from a visible structure to the microscopic group of cells surrounded by the sporophyte tissues. The lower vascular plants like ferns and club mosses are generally homosporous, that is, they produce only a single type of spore while all the seed plants (spermatophytes) are heterosporous. The spermatophytes typically produce 2 types of spores known as th female megaspores and male microspores. The megaspores mature into the female gametophytes producing the eggs while microspores develop into male gametophytes generating sperms. The gametophytes of the seed plants are not free-living as they develop within the spores, unlike the gametophytes of seedless vascular plants.