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A frond is a large leaf
Leaf

In botany, a leaf is an above-ground plant Organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin, to expose the cells containing chloroplast to light over a broad area, and to allow light to penetrate fully into the tissues....
 with many divisions to it, and the term is typically used for the leaves of palm
Arecaceae

Palm or Palmae or Panamea , the palm family, is a family of flowering plants belonging to the Monocotyledon order, Arecales. There are roughly 202 currently known Genus with around 2600 species, most of which are restricted to tropics, subtropics, and warm temperate climates....
s, fern
Fern

A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta....
s or cycad
Cycad

File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
s.

A frond is the leaf
Leaf

In botany, a leaf is an above-ground plant Organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin, to expose the cells containing chloroplast to light over a broad area, and to allow light to penetrate fully into the tissues....
- like structure of a fern
Fern

A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta....
 or alga. The term is colloquially applied to the leaves of palm
Arecaceae

Palm or Palmae or Panamea , the palm family, is a family of flowering plants belonging to the Monocotyledon order, Arecales. There are roughly 202 currently known Genus with around 2600 species, most of which are restricted to tropics, subtropics, and warm temperate climates....
s, cycad
Cycad

File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
s, and plants with pinnately compound leaves.






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Fern Frond Lobed
A frond is a large leaf
Leaf

In botany, a leaf is an above-ground plant Organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin, to expose the cells containing chloroplast to light over a broad area, and to allow light to penetrate fully into the tissues....
 with many divisions to it, and the term is typically used for the leaves of palm
Arecaceae

Palm or Palmae or Panamea , the palm family, is a family of flowering plants belonging to the Monocotyledon order, Arecales. There are roughly 202 currently known Genus with around 2600 species, most of which are restricted to tropics, subtropics, and warm temperate climates....
s, fern
Fern

A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta....
s or cycad
Cycad

File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
s.

A frond is the leaf
Leaf

In botany, a leaf is an above-ground plant Organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin, to expose the cells containing chloroplast to light over a broad area, and to allow light to penetrate fully into the tissues....
- like structure of a fern
Fern

A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta....
 or alga. The term is colloquially applied to the leaves of palm
Arecaceae

Palm or Palmae or Panamea , the palm family, is a family of flowering plants belonging to the Monocotyledon order, Arecales. There are roughly 202 currently known Genus with around 2600 species, most of which are restricted to tropics, subtropics, and warm temperate climates....
s, cycad
Cycad

File:Cycad cone.jpgCycads are a group of seed plants characterized by a large crown of compound Leaf and a stout trunk . They are evergreen, gymnospermous, dioecious plants having large pinnately compound leaves....
s, and plants with pinnately compound leaves. A significant difference is that, unlike the leaves of the latter, fern fronds bear the reproductive structures (spore-bearing structures) of the sporophyte plant. Because many ferns grow fronds that are held more vertical than horizontal, the "upper" and "lower" surfaces of a frond are more correctly referred to as the adaxial and abaxial surfaces, respectively.

A fern frond consists of a stipe, the stem supporting the blade, and the blade consists of both a laminar (flattened) photosynthetic tissue and a rachis—that portion of the stem to which the laminar tissue is attached. The blades of fern fronds may vary from being simple (undivided) to being highly dissected, even "lace-like". If the leaf tissue is undissected, or the dissections do not reach to the rachis, the frond may be described as lobed or pinnatifid. Otherwise, the blade is compound and each large division of the laminar tissue arising from the rachis is called a pinna (pl., pinnae). The main vein or mid-rib of a pinna is known as a costa (pl., costae). Pinnae may be arranged along the rachis either directly opposite one another or alternating up the stem. The arrangement may change from the base of a blade to the tip, as in the example of Blechnum shown below (from base to tip: pinnae opposite to alternate, and pinnatisect to pinnatifid).

Many ferns have pinnae that are divided two or more times, and the level of division of the fronds is termed pinnate (or 1-pinnate), or twice-pinnate (2-pinnate), or the like. Each secondary division (division of a pinna) is termed a pinnule, and its mid-vein, a costule. A few species of ferns with divided fronds are not pinnate
Pinnate

Pinnate is a term used to describe feather-like or multi-divided features arising from both sides of a common axis in plant or animal structures, and comes from the Latin word pinna for "feather"....
, but are palmate
Leaf shape

In botany, the following terms are used to describe the shape of plant leaf:* Acicular : Slender and pointed, needle-like* Acuminate : Tapering to a long point...
 or bifurcate
Bifurcate

In law, bifurcation is a judge's ability to divide a trial into two parts so as to render a judgment on a set of legal issues without looking at all aspects....
.

Fern Frond Pinnate
On some or all mature blades (usually on the abaxial surface) occur sporangia
Sporangium

A sporangium is a plant or fungus structure producing and containing spores. Sporangia occur in Flowering plant, gymnosperms, ferns, fern allies, bryophytes, Algaee, and Fungus....
, which bear the spore
Spore

In biology, a spore is a reproduction structure that is adapted for biological dispersal and surviving for extended periods of time in unfavorable conditions....
s. The sporangia are clustered in a sorus
Sorus

A sorus is a cluster of sporangium.In fungi and lichens, the sorus is surrounded by an external layer. In some red algae it may take the form of a depression into the thallus....
 (pl., sori) or "fruit dot". Associated with each sorus in many species is a membranous structure called an indusium: an outgrowth of the blade surface that may partly cover the sporangial cluster. Fronds also may bear hairs or scales, glands, and, in some species, bulblets for vegetative reproduction.

Each frond arises from the stem or rhizome
Rhizome

In botany, a rhizome is a characteristically horizontal plant stem of a plant that is usually found underground, often sending out roots and shoots from its nodes....
, which in most species is concealed in the ground or creeps along the ground (or branch or rock) surface. Growth of a fern frond differs from that of a leaf of a flowering plant
Flowering plant

The flowering plants or angiosperms are the most widespread group of Embryophytes. The flowering plants and the gymnosperms are the only extant groups of Spermatophyte....
. The fern frond unrolls from a tightly-coiled structure called a "fiddle-head" (see circinate vernation
Vernation

Vernation is the formation of new leaf or frond. In plant anatomy, it is the arrangement of leaves in a bud.In pine, new leaves are short and encased in sheaths....
).

Some fern species feature frond dimorphism
Frond dimorphism

Frond dimorphism refers to a difference in ferns between the fertile and sterile fronds. Since ferns, unlike flowering plants, bear spores on the leaf blade itself, this may affect the form of the frond itself....
, in which fertile and sterile fronds differ in appearance and structure.