Lecture on Seed Plants and Gymnosperms

These flashcards cover key vocabulary terms related to seed plants and gymnosperms as discussed in the lecture.

Gymnosperm

A type of seed plant whose seeds are not enclosed by an ovary, literally meaning 'naked seed'.

Ovule

The structure that develops into a seed after fertilization, containing the embryo.

Heterosporous

Plant species that produce two distinct types of spores: megaspores and microspores.

Microspore

A small spore that develops into a male gametophyte and ultimately produces pollen.

Mega-gametophyte

A female gametophyte that develops within a megaspore.

Pollination

The process of transferring pollen from the male anther to the female ovule.

Sporophyte

The diploid phase of the plant life cycle that produces spores through meiosis.

Gametophyte

The haploid phase of the plant life cycle that produces gametes.

Progymnosperms

Extinct groups of plants that are the ancestors of gymnosperms and are characterized by woody attributes.

Integument

The outer layer of the ovule that develops into the seed coat after fertilization.

Megasporangium

A structure that produces megaspores, which develop into female gametophytes.

Fertilization

The fusion of sperm and egg cells to form a zygote, leading to the formation of embryos.

Coniferophyta

The phylum of gymnosperms that includes cone-bearing plants, also known as conifers.

Cycadophyta

The phylum of gymnosperms that includes cycads, which are often palm-like and found in tropical regions.

Ginkgophyta

The phylum of gymnosperms that consists only of Ginkgo biloba, known as a living fossil.

Gnetophyta

The phylum of gymnosperms that includes three genera: Gnetum, Ephedra, and Welwitschia.

Seed

The mature ovule containing an embryo, stored food, and a protective seed coat.

Sporic meiosis

A type of life cycle where plants undergo alternation of generations between sporophyte and gametophyte phases.

Strobili

Cone-like structures in seedless plants that have evolved into the cones of gymnosperms.

Vascular cambium

A layer of tissue that produces secondary growth in plants, characteristic of woody seed plants.