Gymnosperms: General Introduction and Biology of Pinus

A set of vocabulary flashcards covering the definitions, anatomical structures, reproductive processes, and economic importance of gymnosperms based on the Biology Grade 11 curriculum.

Gymnosperm

Derived from Greek ('Gymnos' meaning naked and 'sperma' meaning seed), these are plants where seeds are not enclosed within a fruit.

Theophrastus

The individual who first used the word 'gymnosperm'.

Mesozoic era

The geological era (specifically the Jurassic and Cretaceous periods) when gymnosperms were the dominant plants.

Xerophytic

Plant adaptations for survival in dry environments or where water is primarily source from snow rather than rain.

Sporophyte

The dominant generation in the life cycle of gymnosperms, differentiated into root, stem, and leaves.

Coralloid root

A type of root found in Cycas that is symbiotically associated with algae.

Mycorrhizal root

A type of root found in Pinus that has a symbiotic association with fungi to assist in absorption and fixation.

Dimorphic

The condition of having two types of a structure, such as the dwarf and long shoots or the foliage and scale leaves in Pinus.

Heterosporous

Producing two different types of spores: microspores and megaspores.

Sporophylls

Special leaf-like structures on which sporangia develop, which aggregate to form cones or strobili.

Anemophilous

A mode of pollination that occurs by wind.

Monoecious

A condition in Pinus where both male and female reproductive organs develop on the same individual tree.

Spurs

Dwarf shoots in Pinus that consist of a cluster of needle-like foliage leaves.

Microsporophylls

Specialized leaves in the male cone, also called stamens, which bear microsporangia (pollen sacs).

Anatropous

The inverted orientation of the ovule (megasporangium) in Pinus where the micropylar end is directed toward the central axis.

Bract and Ovuliferous scales

The two types of scales found in the female cone of Pinus; the latter bears two ovules on its upper side.

Archegonia

Flask-shaped female reproductive structures in the gametophyte, consisting of a venter, a short neck, and a large egg (oosphere).

Zygote (Oospore)

The first cell of the sporophyte generation, formed by the fusion of a male nucleus and the egg.

Chilgoza

Edible seeds obtained from Pinus gerardiana.

Ephedrine

An alkaloid yielded from Ephedra used to treat asthma, cough, cold, and bronchitis.

Taxol

An anti-cancerous drug obtained from the bark of Taxus.

Tannin

A substance extracted from the bark of Araucaria used in the leather industry.

Radicle and Plumule

The components of a mature embryo; the radicle is directed toward the micropylar end and the plumule toward the inner side.