Bract

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Bract

In botany

Botany

Botany, plant science, phytology, or plant biology is a branch of biology and is the Scientific method of plant life and development....
, a bract is a modified or specialized 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....
. Bracts are ordinarily associated with reproductive structures (subtending flower

Flower

A flower, sometimes known as a bloom or blossom, is the reproduction structure found in flowering plants . The biological function of a flower is to mediate the union of male sperm with female ovum in order to produce seeds....
s, inflorescence

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a Plant stem that is composed of a main branch or a complicated arrangement of branches....
axes, or cone scales). They are ordinarily reduced in size relative to foliage leaves, or of a different color or texture from foliage leaves, or both.

Some bracts are brightly colored and serve the function of attracting pollinators, either in concert with or instead of the perianth.

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Encyclopedia

In botany

Botany

Leaf

Flower

Inflorescence

Poinsettia

Euphorbia pulcherrima, commonly named poinsettia, is a species of flowering plant indigenous to Mexico and Guatemala.The name "poinsettia" is after Joel Roberts Poinsett, the first United States Ambassador to Mexico, who introduced the plant into the United States in 1828....
plant (Euphorbia pulcherrima).

A small bract is called bracteole or bractlet. Technically it is any bract that arises on a pedicel instead of subtending it. In grasses, the bracts that enclose the florets are termed glume
Chaff

Chaff is the inedible, dry, scaly protective casings of the seeds of cereal grain, or similar fine, dry, scaly plant material such as scaly parts of flowers, or finely chopped straw....
s.

Bracts that appear in a whorl subtending an inflorescence are collectively called an involucre. An involucre is a common feature under the inflorescences of many Apiaceae

Apiaceae

The Apiaceae or Umbelliferae is a family of usually aromatic plants with hollow stems, commonly known as umbellifers. It includes cumin, parsley, carrot, coriander/cilantro, dill, caraway, fennel, parsnip, celery, Queen anne's lace and other relatives....
, Asteraceae

Asteraceae

Polygonaceae

Polygonaceae is a family of flowering plants also known as the "knotweed family" or "smartweed family". The name is based on the genus Polygonum....
. Each flower in an inflorescence may have its own whorl of bracts, in this case called an involucel. Many asteraceous

Asteraceae

The family Asteraceae or Compositae is the largest family of flowering plants, in terms of number of species.The name 'Asteraceae' is derived from the type genus Aster , while 'Compositae', an older but still valid name, means composite and refers to the characteristic inflorescence, a special type of pseudanthium found in o...
plants have bracts both at the flower base and inflorescence base. Those at the flower base — chaff
Chaff

Chaff is the inedible, dry, scaly protective casings of the seeds of cereal grain, or similar fine, dry, scaly plant material such as scaly parts of flowers, or finely chopped straw....
(paleae or receptacular bracts) — are usually minute scales or bristles. Those at the base of the inflorescence or head

Head (botany)

The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae shows lesser degrees of specialization....
— the involucral bracts (phyllaries) — are often green, narrow, and leafy.

A prophyll is a leaf-like structure, such as a bracteole, subtending a single flower or pedicel. The term can also mean the lower bract on a peduncle.

A spathe
Spathe

Spathe may refer to:*A hood-like bract, found along with a spadix, of inflorescences on plants in the arum family *A leaf-like bract subtending an inflorescence in various Genus in the dayflower family ...
is a large bract that forms a sheath to enclose the flower cluster of certain plants such as 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 and arum

Arum

Arum is a genus of about 25 species of flowering plants in the family Araceae, native to Europe, northern Africa, and western Asia, with the highest species diversity in the Mediterranean region....
s. In many arums, the spathe is petal-like, attracting pollinators to the flowers arranged on a type of spike called a spadix

Spadix

In botany, a spadix is a type of raceme: an inflorescence with small flowers crowded on a thickened, fleshy axis. The term is applied to certain monocotyledons, especially members of the Family Araceae called arums or aroids....
.

The frequently showy pair of bracts of cyathia

Cyathium

The very special Pseudanthium in the genus Euphorbia are known as Cyathia. A cyathium consists of:* five bracteoles. These are small, united bracts, which form a cup-like involucre....
of Euphorbia species in subgenus Lacanthis is termed cyathophylls.

Bracts subtend the cone scales in the seed cones of many conifers, and in some cases, such as Pseudotsuga, extend beyond the cone scales even in mature cones.

Bract

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