Gymnosperms and Angiosperms
February 4, 2008
Vocabulary
Gymnosperms Ginkgophyta Coniferophyta Cycadophyta Ginkgo ovulate cone
pollen cone Monocot Dicot Cotyledon Flower carpel stamen ovary
Double Fertilization endosperm Perfect/Imperfect flower Fruit seed
1. Fill in the following table to compare bryophytes, ferns, gymnosperms and angiosperms.
Bryophytes / Ferns / Gymnosperms / AngiospermsClades included / Hepatophyta(liverworts)
Anthecerophyta(Hornworts)
Bryophyta(mosses) / Lycophyta, Pterophyta / Coniferophyta
Cycadophyta
Ginkgophyta / Monocot
Dicot
Dominant stage / Gametophyte / Sporophyte / Sporophyte / sporophyte
Vascular tissue? / No / Yes / Yes / yes
Seeds? / No / No / Yes- naked / Yes- covered
Branched sporophytes? / No / Yes / Yes / yes
Is a life stage dependent? / Yes-sporophyte on gametophyte / No / Yes- gametophyte / Yes- Gametophyte
Needs moisture? Why? / Yes- for sperm to swim to egg / Yes- for sperm to swim to egg / Not for sperm transfer / Not for sperm transfer
Flowers and Fruits? / No / No / No / Yes
Mode of transfer of male gamete / Moisture / moisture / Wind / Wind, animals, birds, insects
Type of fertilization / normal / normal / normal / DOuble
2. Explain the characteristics of conifers.
reduced needle-like leaves
– pollination is wind-dependent (compare to animal-dispersed in many angiosperms)
– almost all are evergreens
– vascular tissue
– pollen & seeds (usually naked) borne in cones
3. Compare and contrast the life-cycle of gymnosperms and angiosperm.
Look at the Life-cycles at the end of the worksheet. Major difference- Angiosperms have flower and fruits, they have double fertilization. Gymnosperms don’t have flowers and fruits- they have cones. They don’t have double fertilization.
4. Differentiate between monocots and dicots based on their cotyledons, leaves, vascular bundles, roots, and flowers.
Cotyledon leaves Vascular bundle Root Flowers
Monocot one parallel veins complexly arranged Fibrous Root system Floral parts
in multiples of 3
Dicot two net-like veins arranged in a ring Tap Root System Floral parts in
Multiples of 4 or 5
5. What are different parts of a seed and function of each?
Embryo- grow into new plant
Cotyledons- grow into stem, also food source
Radical- grow into roots
Endosperm- food storage
6. Draw a perfect flower and an incomplete flower and label each parts.
A perfect flower has both stamen and carpel present.
An imperfect flower doesn’t have both parts present but only one of them- so the flower will either have stamen only- male flower or carpel only- female flower.
7. Explain the fertilization process in angiosperms.
Look at the life cycle.
Double fertilization takes place in which a sperm fuses with an egg to form zygote(2n) that then develops into embryo. The other sperm then fuses with two cells(nuclei) present at the center of embryo sac (ovule) to form endospore(3n) that acts as food reserve.
8. Explain different forms of pollination and seed dispersal and also talk about coevolution in animals and plants.
Pollination by insects, birds, mammals etc. Flowers need to be colorful and attractive, may be smell better or taste better. Also they need to have more nectar.
The animals need to be able to see colors, also visualize UV radiation and able to guide the group to the flower like in bee- bee dance.
Seed dispersal- The fruit and seed needs to be have food, the seeds should not be digested by the animals. Also the seeds might have special structures so that they can stick to the body and be transferred.
9. What are plants important to us?
There are so many like food source, source of oxygen, medicine, antibiotics and so on.
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Life Cycle of Angiosperms