plant reproduction

Bryophytes

Earliest land plant, grew low to the ground, don't have roots and need to live in moist environments.

Nonvascular plants

Rootless, move water by diffusion through their tissues, very slow.

Bryophyte reproduction

They rely on water, they have no flowers or pollen. Reproduction needs a lot of water.

Haploid

2 generation reproduction system. Adult, one set of chromosomes, male or female.

Diploid

2 sets of chromosomes (hermaphroditic).

Reproduction process

Male haploid sperm fertilizes egg, diploid embryo is formed, diploid mass developed from embryo (asexual), haploid spores.

Peat bogs

Formed by dead plants accumulated in wet low oxygen environments.

Importance of bogs

They store carbon which helps reduce climate change.

Vascular plants adaptation

Vascular tissues and tubes that transport water and nutrients. Allows larger growth and in drier environments.

Xylem

Carries water and nutrients from roots to plants.

Phloem

Carries sugar from leaves to plants.

Ferns and primitive vascular plants reproduction

Reproduce with spores.

Difference between bryophytes and ferns

Ferns are taller, spores are dispersed by wind but still need water.

Seed

Embryonic plant and nutrients inside a protective coat.

Endosperm

Provides nutrients and water for new plants, stores water and nutrients for embryo.

Gymnosperm

Vascular, non-flowering seeds in a cone. Rely on wind for pollination (ineffective).

Gymnosperm vs. bryophyte reproduction

Gymnosperms do not have haploid generation; instead, they have diploid but still produce haploid sex cells.

Gymnosperm reproduction cycle

Pollen and ovules in male and female cones, wind carries pollen, pollen contacts female cones and fertilizes ovule, embryo -> seed -> dispersed by wind.

Angiosperm

Flowering plant, vascular plant, seed enclosed in ovary, makes up 90% of species.

Cotyledon

Structure in embryos that becomes the first embryonic leaf.

Monocots characteristics

1 cotyledon, parallel veins, randomly scattered, floral parts in 3s, fibrous roots.

Eudicots characteristics

2 cotyledons, branching veins, orderly ring arrangement, 4/5 floral parts, taproot.

Flowers

Reproductive part of angiosperm; petals and sepals are modified leaves; male and female reproductive parts in one flower.

Stamen

Male reproductive part of the flower.

Anther

Male part of stamen that produces pollen.

Filament

Supporting stalk of the anther in the flower.

Carpel

Female reproductive part of flower.

Stigma

Female part that receives pollen (sticky).

Style

Elongated stalk of stigma in female reproductive part of flower.

Ovary

Part of female reproductive that contains ovules.

Pollination

Transfer of pollen from anther to stigma (angiosperm of the same species).

Fertilization

Two gametes fuse and form a zygote.

Gametes

Reproductive cells.

Zygotes

Diploid cell formed by fusion of two gametes.

Fertilization of angiosperm

Diploid flower produces haploid pollen, sperm travels down the pollen tube, sperm fertilizes the ovule, creates a diploid zygote and then develops into a seed.

Seed dispersal

Wind (light weights have wings/tufts), animals (edible fruit, or stick to animals), water (large or float), fruit (ripened ovary).

Physical defense

Thorns, bark, sticky traps.

Chemical defense

Toxics, repellents, compounds.

Human uses of plants

Plant defense -> medicine and pesticides; willow bark -> aspirin; opium -> pain killers; cannabis -> pain/anxiety relief.