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Pea

A pea, although treated as a vegetable in cooking, is botanically a fruit; the term is most commonly used to describe the small spherical seeds or the pods of the legume Pisum sativum. This was the original model organism used by Gregor Mendel in ...

Xenopus

Xenopus commonly known as the clawed frog) is a genus of aquatic frogs native to sub-Saharan Africa. Twenty species are known. The two best-known species of this genus are Xenopus laevis and Xenopus tropicalis, which are studied as model organism ...

Plant

Plants are one of six big groups of living things. They are autotrophic eukaryotes, which means they have complex cells, and make their own food. Usually they cannot move. Plants include familiar types such as trees, herbs, bushes, grasses, vines ...

Abutilon

Abutilon is a scientific group of plants. It a genus the family Malvaceae. Abutilon has about 150 species of evergreen plants in it. The genus includes plants that die every year plants that grow back every year, shrubs, and trees of approximatel ...

Bract

In botany, a bract is a modified leaf, especially one associated with a flower or inflorescence. Bracts are usually different from normal leaves. They may be smaller, larger, or of a different color, shape, or texture. Usually, they also look dif ...

Climax community

In ecology, climax community is a term for a stable biological community of plants, animals and fungi. After a process of ecological succession the vegetation in an area reaches a steady state. Its stability is not guaranteed: invasive species an ...

Essential oil

An essential oil is a liquid from a plant. Essential oils contain chemical compounds that are useful for their scent. They are used in aromatherapy. Perfumes are made with essential oils. Around the world, essential oils are being studied in mode ...

Garden

A garden is usually a piece of land that is used for growing flowers, trees, shrubs, and other plants. The act of caring for a garden by watering the flowers and plants and removing the weeds is called gardening.

Hemp

This article is about the cultivation and uses of hemp. For the biology of the plant, see Cannabis. For the drug, see Cannabis drug. For other uses of the word hemp, see Hemp disambiguation. Hemp is a plant and the fibers made from it. It is a su ...

Plant pathology

Plant pathology, or phytopathology, is the study of plant diseases. Like animals, plants can get infected and damaged by viruses, bacteria and fungi. It includes not only the harm done by pathogens infectious organisms, but also harm done by envi ...

Plants of Connecticut

Connecticut has a variety of plant species. Connecticut belongs to the North American Atlantic Region. The state flower is the Mountain Laurel. The state tree is the White Oak; or more specifically, the Charter Oak.

Ploidy

Ploidy is a term from genetics and cell biology. It is used to indicate the number of chromosome sets in a cell. Most eukaryotes have either one set or two sets. Some other organisms are polyploid, they have more than two sets of chromosomes. Som ...

Pollination

Pollination is part of sexual reproduction in plants. It describes how the pollen grains get to the female parts of a plant. Pollen grains, which contain the male gametes, need to get to where the female gamete are. What happens is basically the ...

Sanmiguelia

Sanmiguelia is a genus of the fossil plants, possible may be among the earliest of angiosperms. It was determined on the basis its imprints of palm-shaped leaves originated from Triassic geological period. They were found in rocks from Colorado. ...

Seed dispersal

Seed dispersal is the way seeds get away from the parent plant to a new place. "Dispersal" means to spread or scatter. The basic idea is as follows. Plants, obviously, cannot move after they have put down roots. It follows that it is an evolution ...

Shade-loving plants

In ecology, shade tolerance refers to a plants ability to grow with low light levels. The term is also used in gardening and landscaping. Sometimes called "shade-loving" plants, they can be grown without a lot of sunshine. Most urban gardeners mu ...

Shamrock

Shamrocks are the young sprigs of clover or trefoil. The shamrock is a symbol of Ireland. According to a legend, Saint Patrick used it to illustrate the doctrine of the Holy Trinity. The name shamrock is derived from Irish seamrog. This is the di ...

Stolon

Stolon is a term used often in botany. It describes a horizontal stem running across or just under the ground. A runner is a stolon which runs on the ground; a rhizome is the same thing, but running underground. Rhizome can be found in Ginger, Tu ...

Tumbleweed

Several plant species that grow in arid, steppe-like environments use the wind to propagate. The structure that is pushed by the wind is usually called tumbleweed. This structure will detatch from its root or stem and will roll on the ground. In ...

Archaea

The Archaea are a group of single-celled organisms. The name comes from Greek αρχαία, "old ones". They are a major division of living organisms. Archaea are tiny, simple organisms. They were originally discovered in extreme environments extremoph ...

CRISPR

CRISPR is a term used in microbiology. It stands for Clustered Regularly-Interspaced Short Palindromic Repeats. These are a natural segment of the genetic code found in prokaryotes: most bacteria and archaea have it. CRISPR has a lot of short rep ...

Earliest known life forms

The earliest known life forms found on Earth are fossils of microorganisms in 3.46 billion year old rocks in Western Australia. Life forms, as microorganisms, may have lived much earlier. The earliest time that life forms first appeared on Earth ...

Hadesarchaea

Hadesarchaea are very small living things. They are thermophile Archaea that live in very hot places underground. People have found them in sand at the bottom of the ocean, deep mines, hot springs, and other places underground.

Human microbiome

The human microbiome is the collection of microorganisms which live on us. They live on the skin, in the saliva and mouth, in the eyes, and in the gut and the rest of the gastrointestinal tract. They include bacteria, archaea, fungi and single-ce ...

Microbiology

Microbiology - is a science in the composition of biology, which is occupied by the study of microorganisms, microscopic fungi, protozoa,alga,and viruses). Into the field of the interests of microbiology enter their systematics, morphology, physi ...

Origin of life

The origin of life on Earth is a scientific problem which is not yet solved. There are many ideas, but few clear facts. Most experts agree that all life today evolved by common descent from a single primitive lifeform. It is not known how this ea ...

Transduction (genetics)

Transduction is the process by which DNA is transferred from one bacterium to another by a virus. Joshua Lederberg and his graduate student Norton Zinder showed in 1952 that bacteriophages could transfer genetic information between bacteria in Sa ...

Protist

Protists are single-celled eukaryotes. The term Protista was first used by Ernst Haeckel in 1866. The protists are not a natural group, or clade, since they have no common origin. Like algae or invertebrates, they are often grouped together for c ...

Acritarch

Acritarchs are early microfossils, the remains, probably, of eukaryote cells. It is the resistant single-layered cell walls, or perhaps a cover secreted by cell walls, that we see in early rocks of the Proterozoic era. These structures are organi ...

Amnesic shellfish poisoning

Amnesic shellfish poisoning is an illness caused by poisoning with a particular toxin called domoic acid. At times, some diatoms produce domoic acid in ocean water. Shellfish accumulate this poison, and when they are eaten by people, the people g ...

Coccolith

Coccoliths are the microscopic algae which form chalk. They are made by one of the most important eukaryote phytoplankton. These are single celled protists whose full name is coccolithophorids or coccolithophores. The spherical skeleton of coccol ...

Diatom

Diatoms are a big group of eukaryotic algae. They are one of the most common types of phytoplankton. Most diatoms are unicellular, although some form chains or simple colonies. Diatom cells are encased within a unique cell wall made of silica. Th ...

Euglena

Euglena is a large genus of unicellular protists: they have both plant and animal characteristics. All live in water, and move by means of a flagellum. This is an animal characteristic. Most have chloroplasts, which are characteristic of algae an ...

Euglenozoa

The Euglenozoa are a large phylum of flagellate protists. They are part of the wastebasket taxon known as the Protozoa, which contained many obviously different protists. Euglenozoa include a variety of common free-living species, and some import ...

Extremophile

An extremophile is an organism which lives best in extreme conditions that are harmful to most life on Earth. They are different from organisms that live in normal places, called mesophiles or neutrophiles. In the 1980s and 1990s, biologists foun ...

Flagellum

A flagellum is a long, whip-like structure that helps some single celled organisms move. It is composed of microtubules. They help propel cells and organisms in a whip-like motion. The flagellum of eukaryotes usually moves with an" S” motion, and ...

Foraminifera

Foraminifera or forams, as they are called, are an important group of tiny single-celled rhizarian eukaryotes. They are mostly marine, though a few live in fresh-water, and even on damp land areas. In the sea, they live both in the plankton, and ...

Great Oxygenation Event

The Great Oxygenation Event was the introduction of free oxygen into our atmosphere. It was caused by cyanobacteria doing photosynthesis. It took a very long time, from about three billion years ago to about one billion years ago. Photosynthesis ...

Grypania

Grypania is an early, tube-shaped fossil from the Proterozoic eon. It is regarded by some as the first known eukaryote. Grypania s status as a eukaryote is not absolutely proven. It might have been a giant bacterium or bacterial colony. Its size ...

Haptophyte

Haptophytes are a phylum of algae, sometimes called the Prymnesiophyta. All or most of them are single-celled photosynthetic phytoplankton. The cells typically have two slightly unequal flagella and a unique organelle called a haptonema. This is ...

Hydrothermal vent

A hydrothermal vent is an opening in the seabed of the Earth by which geothermal energy escapes. Sea water enters, becomes very hot, and rises. The hottest ones carry many black chemicals, and are called black smokers. Scientists have found fewer ...

Kinetoplastid

The kinetoplastids are a group of single-cell flagellate eukaryotes. They include a number of parasites responsible for serious diseases in humans and other animals. There are also forms found in soil and aquatic environments. They are members of ...

Leishmania

Leishmania is a protist organism which causes Leishmaniasis. It is a Trypanosomatid parasite in the Euglenozoa phylum. It is spread by sandflies of the genus Phlebotomus in the Old World, and of the genus Lutzomyia in the New World. Their primary ...

Noctiluca scintillans

Noctiluca scintillans, is the sea sparkle. It is a free-living marine-dwelling species of dinoflagellate. It shows bioluminescence when disturbed: this produces a "milky seas effect". The bioluminescence is produced in the cytoplasm of this singl ...

Oomycete

The Oomycota are a class in a huge phylum of eukaryotic microorganisms called the Heterokonts. Oomycetes are a distinct phylogenetic lineage of fungus-like microorganisms. They are not actually fungi, though some have filaments as fungi do. Like ...

Potato blight

Potato blight is the so-called "fungal" disease which destroyed the Irish potatoes in 1845. Because there are other blights of potatoes, this one is sometimes called late blight of potato. The infestation caused widespread famine. It was caused b ...

Radiolaria

Radiolaria are amoeboid protists which produce mineral skeletons. The skeletons, usually of silica, have a central capsule. This divides the cell into inner and outer portions, called endoplasm and ectoplasm. Radiolaria are found as zooplankton t ...

Slime mould

Slime moulds, or slime molds, are forms of life which live on the rainforest floor, and many other parts of the world. They slither over ground and fallen tree trunks in search of food. They scatter spores, like plants, which grow into new slime ...

Thermophile

A thermophile is an organism – a type of extremophile – that thrives at relatively high temperatures. That means between about 40 and 120 °C. Many thermophiles are archaea. Thermophilic eubacteria may have been among the earliest bacteria. Thermo ...

Bacteriophage

A bacteriophage is a virus that infects bacteria. The term is commonly shortened to phage. Bacteriophages are among the most common and diverse entities in the biosphere. Like viruses that infect eukaryotes there are many different phage structur ...

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