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Found Angiosperms 10 times.

Displaying results 1 to 10.

1. Angiosperms
Flowering plants. first appearing at least 110 million years ago from an unknown gymnosperm ancestor, flowering plants have risen to dominance in most of the world's floras. The male gametophyte is 2-3 cells contained within a pollen grain; the female gametophyte is usually eight cells contained within an ovule which is retained on the sporophyte phase of the plant's life cycle.

2. Dicotyledon (dicot)
A subclass of of angiosperms . They tend to have: * broad leaves * two cotyledon s * netlike veins in the leaves * flower parts are usually in fours or fives * a ring of primary vascular bundles in the stem * taproot system. Compare: monocot

3. Double fertilization
A characteristic of angiosperms in which a pollen tube carries two sperm cells to the female gametophyte in the ovule . One sperm cell fuses with the egg cell and gives rise to a diploid embryo The other sperm cell fuses with the two polar cells to form a triploid cell that develops into the endosperm .

4. Endosperm
A food storage tissue that provides nutrients to the developing embryo in angiosperms ; formed from the triploid cell produced when a sperm cell fertilizes the central cell. Some endosperm is solid (as in corn), some is liquid (as in coconut).

5. Jurassic Period
Middle period of the Mesozoic Era , between 185-135 million years ago. Characterized by the (possible) origin of angiosperms and the continued split of the worldwide supercontinent of Pangaea.

6. Kaemferol
A flavone-ring-containing plant pigment found in many angiosperms (flowering plants).

7. Monocots
One of the two major types of flowering plants; characterized by having a single cotyledon , floral organs arranged in threesd or multiples of three, and parallel-veined leaves; include grasses, cattails, lilies, and palm trees. One of the two major groups in the angiosperms , monocots are characterized by having a single seed leaf (cotyledon), flower parts in 3's or multiples of 3, monoaperturate pollen (although some dicots also have this feature), parallel veins in their leaves, and scattered vascular bundles in their stems.

8. Pollen tube
Structure produced by the tube nucleus in the pollen grain through which the sperm nucleus (or nuclei in angiosperms ) proceed to travel through to reach the egg.

9. Synergid
Cells in the embryo sac of angiosperms that flank the egg cell. The pollen tube grows through one (usually the smaller) of the synergids.

10. Vessel elements
Short, wide cells arranged end to end, forming a system of tubes in the xylem that moves water and solutes from the roots to the rest of the plant. Large diameter cells of the xylem that are extremely specialized and efficient at conduction. An evolutionary advance over tracheids. Most angiosperms have vessels.

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