Plant and Fungi Life Cycles Review

Flashcards covering key vocabulary related to plant and fungi life cycles, ploidy, and reproductive strategies discussed in the lecture.

Haploid (N)

Refers to cells or organisms having one set of chromosomes.

Diploid (2N)

Refers to cells or organisms having two sets of chromosomes.

Fungi Ploidy

The general life stage of an individual fungus is typically haploid.

Meiosis

A special type of cell division that reduces the chromosome number by half (from diploid to haploid) and creates genetic variation, primarily occurring in diploid cells.

Mitosis

A type of cell division that produces exact genetic copies of cells and is the main process for growth and development; can occur in haploid, diploid, or polyploid cells.

Zygotic Meiosis

A life cycle type where meiosis occurs immediately after the formation of the zygote, often found in fungi.

Gametic Meiosis

A life cycle type where meiosis produces gametes (sperm and egg), as seen in humans and most animals.

Sporic Meiosis

A life cycle type where meiosis produces spores, as seen in most plants.

Plant Cell Walls

Composed of cellulose, a type of carbohydrate.

Fungi Cell Walls

Composed of chitin.

Autotrophs

Organisms that are capable of producing their own food, typically through photosynthesis, like plants.

Chlorophyta

A specific group of green algae believed to be the ancestors of land plants.

Pollination

The process by which plants rely on animals (especially insects) or wind to transfer pollen, aiding in reproduction.

Pollen

A structure in plants that is 'pre-sperm,' which will germinate on the correct flower to produce sperm.

Fruit

A mature ovary of a flowering plant, typically containing seeds and often designed to be eaten by animals for seed dispersal.

Seed Dispersal

Mechanisms by which seeds are moved away from the parent plant, such as by wind (e.g., maple 'helicopters,' tumbleweed) or animals.

Alternation of Generations

A plant life cycle characterized by the alternation between a diploid sporophyte form and a haploid gametophyte form within the same individual.

Sporophyte

The diploid (2N) form or generation of a plant that produces haploid spores via meiosis.

Gametophyte

The haploid (N) form or generation of a plant that produces haploid gametes (eggs and sperm) via mitosis.

Sporangium (Sporangia)

The generic structure within a sporophyte where spores are produced through meiosis.

Spore Mother Cell

A diploid cell located within the sporangium that undergoes meiosis to produce haploid spores.

Archegonium

A mitotically produced reproductive structure within the gametophyte that produces eggs.

Antheridium

A mitotically produced reproductive structure within the gametophyte that produces sperm.

Plasmogamy

The first stage of syngamy (fertilization) involving the fusion of the cytoplasm from two different gametes or cell types.

Dikaryotic Stage (N+N)

An intermediate ploidy condition, particularly prominent in fungi, where a cell contains two unfused haploid nuclei.

Karyogamy

The second stage of syngamy, involving the fusion of two haploid nuclei to form a diploid nucleus.

Syngamy

The complete process of fertilization, encompassing both plasmogamy and karyogamy, leading to the formation of a zygote.

Heteromorphic Alternation of Generations

A type of alternation of generations where the sporophyte and gametophyte are morphologically distinct from each other (e.g., most plants).

Isomorphic Alternation of Generations

A type of alternation of generations where the sporophyte and gametophyte are morphologically identical but differ in ploidy (e.g., many algae).

Gametophyte Dominant Life Cycle

A type of plant life cycle where the haploid gametophyte stage is the more prominent, independent, and long-lived form (e.g., mosses).

Sporophyte Dominant Life Cycle

A type of plant life cycle where the diploid sporophyte stage is the more prominent, independent, and long-lived form (e.g., ferns, flowering plants).

Homosporous

Refers to plants that produce only one type of spore, which develops into a bisexual gametophyte (e.g., most ferns).

Heterosporous

Refers to plants that produce two morphologically different types of spores: microspores and megaspores (e.g., seed plants).

Microspore

A smaller, haploid spore produced by heterosporous plants, which develops into a male gametophyte (pollen grain).

Megaspore

A larger, haploid spore produced by heterosporous plants, which develops into a female gametophyte (within the ovule).