Biology: Cell Division, Plant Life Cycles, and Reproduction Types 2

Mitosis

Produces 2 cells

Meiosis

Produces 4 cells

Mitosis cells

Identical (clones) to the parent cell

Meiosis cells

Different from the parent cell

Somatic cells

Type of cells that undergo mitosis

Germ cells

Type of cells that undergo meiosis (gametes)

Main function of mitosis

Growth, repair, and asexual reproduction

Main function of meiosis

Sexual reproduction

Asexual reproduction

Produces clones

Sexual reproduction

Increases genetic variation

Genetic variation generation

Crossing over, independent assortment, fertilization, and outcrossing

Outcrossing

Mating between unrelated individuals → more variation

Selfing

Self-fertilization → less variation

Sperm production in animals

Produced by meiosis, haploid (1n)

Sperm production in plants

Produced by mitosis in haploid gametophyte, haploid (1n)

Importance of dispersal

Reduces competition and allows colonization of new environments

Dispersal methods

Plants → spores, pollen, seeds, fruits; Fungi → spores; Animals → movement of gametes, larvae, or adults

Fungal reproductive steps

Plasmogamy → heterokaryotic hypha → karyogamy → diploid → meiosis → haploid spores

Eukaryotic life cycle phases

Haploid (1n) and diploid (2n)

Haploid and diploid stages in animals

Haploid → gametes; Diploid → zygote and adult

Haploid gametophyte in plants

Produces gametes by mitosis

Unique fungal life cycles

Mostly haploid, heterokaryotic stage, plasmogamy & karyogamy

Major plant groups

Bryophytes → Lycophytes → Ferns & allies → Gymnosperms → Angiosperms

Example of a bryophyte

Moss; gametophyte dominant

Example of a lycophyte

Club moss; sporophyte dominant, simple leaves (microphylls)

Ferns and allies characteristics

Vascular, seedless, sporophyte dominant

Examples of gymnosperms

Conifers, cycads, ginkgo; seed plants with naked ovules

Angiosperms definition

Flowering plants, fruits, double fertilization

Function of apical meristems

Flexible growth from totipotent cells

Purpose of a waxy cuticle

Reduces water loss

Alternation of generations

Plants alternate multicellular haploid (gametophyte) and diploid (sporophyte) stages

Types of vascular tissue

Xylem → water/minerals; Phloem → sugars

Seed composition

Embryo + food + protective coat

Unique feature of angiosperms

Having flowers and fruits