Download presentation
1
Seed Plants
2
Seed plants are divided into two groups:
1. gymnosperms – which bear their seeds directly on the surface of cones. Gymnosperms include conifers such as pine and spruce, palmlike plants called cycads, ginkgoes, and the very weird gnetophytes.
3
Phylum Gymnosperm Gymno = naked sperma = seed
“naked seed” no covering around seed Do not flower Produce cones (acorns, pine) Shallow roots and woody stems Leaves are needle-like and are replaced every 2 – 4 years.
4
Gymnosperm continued Needles retain moisture even during cold seasons.
Grow all year Can grow in harsh environments (cold, poor soil) Used for lumber, making paper, wood chips
5
Pollen cone Seed Cone
6
The pollen falls down into the seed cone and fertilization results in a zygote which grows into an embryo inside a seed. As the seed ripens, the cone opens and releases the seeds. If the ground is favourable, it will grow. The pollen cone releases million of pollen into the air which is why allergies can be triggered in the spring.
8
Life cycle of a gymnosperm
Cones are either male or female: - female cone is the seed cone and found at the bottom of the tree - male cone is the pollen cone and found in the upper tree
9
Angiospermae 2. angiosperms (also called flowering plants) – which bear their seeds within a layer of tissue that protects the plant.
10
Angiospermae Angio = covered seed sperma = seed Covered seed
11
Produce flowers (which are unique reproductive systems)
12
Soft stems (herbaceous)
Broad leaves Deep roots Grow in summer only (deciduous)
13
Pollination Pollination is the pollen moving from the male part of the plant to the female part of the plant.
14
Pollination can take place in 2 ways:
Self-polliation: occurs in some flowers Cross-pollinators: a. birds, insects feed on the nectar. attracted to flower colour, scent, shape therefore they go to the same type of flower carry pollen from plant to plant while feeding
15
b. wind - blows pollen around
16
Success of angiosperm is due to:
Flowers – Do not have to depend on wind or water to fertilize/reproduce Fruit – The wall of tissue that surrounds the seed protects it and is usually delicious. As a result, they are often eaten. By the time the seeds have cleared the animal’s digestive system and are ready to sprout, they may have travelled many kilometers.
18
Angiosperm are categorized in 3 ways:
One way: Two classes with the angiosperm: Monocots (Monocotyledon)and Dicots (Dicotyledon) Monocots and dicots are named for the number of seed leaves or cotyledons in the plant embryo.
19
Seeds of the dicot (left) and monocot (right)
22
Add to chart the chart above (see page 570 in your text:
Monocots Dicots Fibrous root Taproot
23
Another way to group angiosperms
2. By their stems: Woody or herbaceous Woody: trees, grapes, some ivy, blueberries, roses Herbaceous: dandelions, petunias, sunflowers
24
Herbaceous and Woody
25
Another way: 3. Annuals, biennials, perennials
Annuals: Complete their life cycle in one year (grow, flower, produce seeds and die in one year Biennials: complete their life cycle in two years Perennials: live for more than 2 years
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.