Lecture Notes on Gymnosperms and Seed Evolution

Flashcards covering key concepts from the lecture on gymnosperms and the evolution of seeds.

The major stages in heterosporous gametogenesis include whether it is or and whether it is or .

single cellular; multicellular; diploid; haploid

The unique characteristics of Coniferophyta leaves include their arrangements and adaptations for moisture.

needlelike; low

The production of a seed is an extreme form of __.

heterospory

Microgametophytes in most gymnosperms develop as __.

pollen grains

Fertilization in gymnosperms does not require __.

free water

The seed contains an embryo, food stores, and a coat, which develops from __.

integuments

The life cycle of Pines (Pinus) takes up to __ years to complete.

2

Pollination occurs when the scales on the ovulate cone are __.

widely separated

The __ genus includes the tallest living plant, Sequoia sempervirens.

Cupressaceae

Conifers mainly belong to the phylum __ which includes four major groups: Coniferophyta, Cycadophyta, Gnetophyta, and Ginkgophyta.

Coniferophyta

Gymnosperms were thought to have evolved about __ million years ago.

365