gnetophyte, (division Gnetophyta), any member of the division Gnetophyta, a small group of gymnospermous vascular plants that are represented by three living genera: Ephedra, Gnetum, and Welwitschia.

What is an example of Gnetophyta?

Gnetum
MelinjoGnetopsida
Gnetophytes/Lower classifications

gnetophyte, (division Gnetophyta), any member of the division Gnetophyta, a small group of gymnospermous vascular plants that are represented by three living genera: Ephedra, Gnetum, and Welwitschia.

What is the microgametophyte of a pine tree?

These pollen grains are young microgametophyte plants. Study the pine pollen grains in the microsporangia on the pollen cone slide and complete your labeling of Figure 24-2. (1) The adult pine, a sporophyte, produces young male cones near tips of branches.

How does fertilization take place in conifers?

All conifers are pollinated by wind. Pollen may be produced in enormous quantities, particularly by species of true pine (Pinus), which can blanket the surface of nearby lakes and ponds with a yellow scum of pollen (the pollen can cause allergies in humans).

What is a seed cone?

The seed cones are terminal or axillary, cone-like or highly reduced, usually fleshy [rarely dry], in some taxa subtended by a stalk (“peduncle”) that may fuse with bracts, forming a fleshy “receptacle,” ovuliferous scales 1–∞, each bearing a single ovule, in some members a single scale modified as a protective …

Where are Gnetophyta found?

Gnetophyta plants are distributed around much of the world mostly in tropical and temperate climates. The genus Gnetum has a tropical distribution as is found in Southeast Asia, northern South America, the South Pacific and western Africa.

What is the common name for Gnetophyta?

Integrated Taxonomic Information System – Report

Common Name(s):
Accepted Name(s): Tracheophyta
Taxonomic Status:
Current Standing: not accepted – synonym
Data Quality Indicators:

What is the difference between a Megagametophyte and microgametophyte?

As nouns the difference between microgametophyte and megagametophyte. is that microgametophyte is (biology) any gametophyte that develops from a microspore while megagametophyte is (biology) any gametophyte that develops from a megaspore.

What is the Megasporogenesis?

Megasporogenesis refers to the development of megaspores from the megasporocyte, the cell that undergoes meiosis. Meiosis of the megasporocyte nucleus results in the formation of four haploid megaspore nuclei. In most taxa, meiosis is followed by cytokinesis, resulting in four megaspore cells.

Do conifers give off pollen?

In fact Conifers, unlike Broadleaf trees, do not have flowers or fruit. They have male and female cones. The botanical name for a cone is a strobilus. Pollen cones, like male flowers, release pollen and Seed cones, like female flowers, receive pollen and develop seeds.

Do conifers need to be pollinated?

Unlike angiosperms, most of which are insect pollinated (entomophily), the majority of gymnosperms are wind pollinated (anemophily). Conifers are a small group of gymnosperms that dominate north temperate forests. All are wind pollinated, but an array of mechanisms have evolved to increase pollination success.

What does a pollen cone look like?

Brown, tube-like clusters on the branches of a pine, the cones contain scales, or microsporophylls, around a central stem. Each scale holds a pollen sack, or microsporangium, and each pollen sack contains pollen grains, each called a microgametophyte, or microspore.

What does it mean when trees are loaded with pine cones?

But more pine cones can also mean the trees are producing more reproductive seeds as a way to deal with the stress of a dry or changing climate. It’s a matter of survival: The tougher, drier the season, the stronger the urge for the trees to reproduce through seeds so the species can survive.

How to identify other conifers?

How to Identify Other Conifers. 1 Yew ( Taxus) Yew tree topiary (left). Yew foliage and berries (right) Yew trees have dark green glossy needle leaves that are soft and flattened with 2 Hemlock ( Tsuga) 3 Juniper ( Juniperus) 4 Cedar ( Cedrus) 5 Cypress ( Cupressus)

What are conifers classified as?

Conifers are a type of woody plant that belong to the botanical division Pinophyta and class Pinopsida. Apart from firs, spruces, and pines, other trees belonging to the families of conifers include cedar, cypress, yew, and juniper trees.

What are the characteristics of a conifer tree?

For this reason, they are one of the smaller conifer types. They are found in northern regions, particularly in temperate and boreal areas. They are decently large trees that can reach between 60 to 200 feet tall. Their needles are four-sided, and their cones hang downwards after they are pollinated.

What are the different types of ornamental conifers?

Some ornamental conifers are slender, narrow trees, shrubs with a rounded growth, weeping conifers, or short conical trees. Here are some of the best examples of small or dwarf conifers suitable for landscaping gardens: