1. Ch 24- Reproduction of Seed Plants
Life Cycle of Gymnosperms
Reproduction takes place in cones- produced by mature sporophyte plant
2 types of cones- pollen cones and seed cones
Pollen- male
Seed- female
Ovules- base of seed cone where female gametophytes develop
Pollen tube- structure that contains 2 haploid sperm nuclei, one sperm disintegrates and other fertilizes egg

3. Structure of Flowers
Flowers are reproductive organs- composed of sepals, petals, stamens, and carpels
Sepals- outermost circle of flower parts, encloses bud, protects the flower while it is developing
Petals- brightly colored structure just inside the sepals, attracts insects and other pollinators
Stamen- male part of flower, made up of anther and filament
Filament-long, thin structure that supports an anther
Anther- flower structure where haploid male gametophytes are produced
Carpels- innermost part of flower that produces female gametophyte
Ovary- contains ovules from which female gametophytes are produced
Style- narrow stalk of the carpel in flower
Stigma- sticky portion at top of style where pollen grains land

5. Life Cycle of Angiosperms
Reproduction takes place within flower- the seeds develop inside protective structures following pollination and fertilization
Most gymnosperms and some gymnosperms are wind pollinated
Most angiosperms are pollinated by animals
Fertilization in angiosperms
One sperm fuses with egg to form zygote
Second sperm fuses with two polar nuclei to form endosperm- food rich tissue that nourishes the seed
Double fertilization

7. Sec 2- Seed Development/Germination
What is a fruit?
Ripened ovary that contains angiosperm seeds, any seed that is enclosed within its embryo wall
As angiosperm seeds mature, ovary walls thicken to form fruit
Apples, grapes, strawberries
Peas, corn, rice

8. How are seeds dispersed?
By animals, wind, water
What type of seeds are dispersed by animals? By wind and water?
What factors influence dormancy and germination?
Temperature and moisture
Dormancy- period where plant is alive but not growing
Varies between plants
Germination- early growth stage of plant embryo
Seed absorbs water causing it to swell and crack open