Lesson 8- Plants 2 Flashcards
Seed
Dormant, can survive out of water, independent, uses dispersal, seed plants are heterosporous
Pollen
Male gametophyte produces sperm (with no flagella) that flies or transports through water
Gymnosperm Ovule
The ovule is comprised of a (2n) integument, a (2n) megasporangium, and a (n) megaspore.
Gymnosperm Pollen
The (n) pollen/microspore contains a (n) tube cell and a (n) generative cell, which will become a (n) pollen tube and a (n) sperm, respectively.
Fertilization and Seed Formation
The pollen attaches to the micropyle (gap in integuments) of ovule, and the pollen tube extends to the egg that is inside the megaspore.
The integuments become the (2n) seed coat, the female gametophyte becomes (n) nutrients that surround the (2n) embryo.
Gymnosperms
Produce cones/strobilus for reproduction, use wind dispersal, drought tolerant.
Ginkgophyta (gymnosperm)
Ginko biloba, fan-shaped leaves, lacks a cone, has exposed ovules
Cycadophyta (gymnosperm)
Sage palms, palm-like leaves, large cone in middle. Dioecious, meaning there are separate male and female individuals
Gnetophyta (gymnosperm)
3 very different groups
Coniferophyta (gymnosperm)
Monoecious, meaning male and female cones appear on one individual. Needle-like leaves within a cuticle.
Angiosperms
Flowering plants with fruit, most diverse plant group. Petals attract animals, animal pollination is more direct than wind pollination.
Angiosperm Flower Parts
Stamen (male): Anthers that produce pollen, and filaments that support the anthers.
Pistil (female): Stigma collects pollen, style is under the stigma and leads to the ovary that contains the ovules.
Calyx (sepals) and Corolla (petals) surround the flower.
After fertilization….
Ovary becomes fruit, Ovules become seeds
Angiosperm Life Cycle- Male Gametophyte
(2n) Anther has a (2n) microsporangium that, through meiosis, produces (n) microspores/pollen that contains 1 (n) tube cell (that turns into a pollen tube) and 2 (n) generative cells (that become 2 sperm).
Angiosperm Life Cycle- Female Gametophyte
The (2n) integuments surround a (2n) megasporangium which contains a (n) megaspore, this becomes 2 (n+n=2n) polar nuclei and 1 (n) egg
Angiosperm Life Cycle- Fertilization and Seed
Pollen tube releases 2 sperm, 1 fuses w/egg and 1 fuses 1/both polar nuclei (called double fertilization).
Seed Coat (2n)
1 sperm + 1 egg = embryo (2n)
1 sperm + 2 polar nuclei = endosperm (nutrients, 3n)
Clade Monocot
1 cotyledon (embryonic leaf), petals are multiples of 3, parallel-running leaf veins, fibrous scattered roots, corn
Clade Eudicot
2 cotyledon (embryonic leaf), petals are multiples of 4 or 5, net-like leaf veins, taproot, beans
