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Botanical Terms -activation energy (energy of activation)
The energy that must be delivered to a system in order to increase the incidence within it of reactive molecules, thus initiating a reaction. The fact that *enzymes significantly reduce the activation energy of numerous metabolic processes is a crucial characteristic.
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The energy that must be delivered to a system in order to increase the incidence within it of reactive molecules, thus initiating a reaction. The fact that *enzymes significantly reduce the activation energy of numerous metabolic processes is a crucial characteristic.
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Botanical Terms - Activator
An ion of metal that works with an enzyme or its substrate to initiate a chemical reaction.
An ion of metal that works with an enzyme or its substrate to initiate a chemical reaction.
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Botanical Terms -active transport
The transport of substances across a membrane against a concentration gradient. Such processes use energy, the source often being the hydrolysis of *ATP.
The transport of substances across a membrane against a concentration gradient. Such processes use energy, the source often being the hydrolysis of *ATP.
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Botanical Terms -active layer
a layer of seasonally thawed surface soil in a periglacial environment that sits above the permanently frozen *horizon. It can range in thickness from a few centimeters to over three meters. If *silt-sized particles predominate, it may be susceptible to significant expansion upon freezing, and it may become quite mobile throughout the melting process
a layer of seasonally thawed surface soil in a periglacial environment that sits above the permanently frozen *horizon. It can range in thickness from a few centimeters to over three meters. If *silt-sized particles predominate, it may be susceptible to significant expansion upon freezing, and it may become quite mobile throughout the melting process
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Botanical Terms - adaptive pathway
a sequence of tiny adaptive steps as opposed to one big one that allows one to pass an environmental and adaptive threshold and enter a new adaptive zone. Small adjustments add up over time to make the organism essentially pre-adapted to the new environment
a sequence of tiny adaptive steps as opposed to one big one that allows one to pass an environmental and adaptive threshold and enter a new adaptive zone. Small adjustments add up over time to make the organism essentially pre-adapted to the new environment
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Botanical Terms -actual evapotranspiration (AE)
The amount of water that evaporates from the surface and is transpired by plants if the total amount of water is limited
The amount of water that evaporates from the surface and is transpired by plants if the total amount of water is limited
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Botanical Terms - adaptive breakthrough
A shift in the course of evolution brought about by the adoption of a unique adaptation that allows a population or taxon to shift from one compatible zone to another. Such movements could, at their most extreme, be from air to land or from sea to land.
A shift in the course of evolution brought about by the adoption of a unique adaptation that allows a population or taxon to shift from one compatible zone to another. Such movements could, at their most extreme, be from air to land or from sea to land.
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Botanical Terms -aculeate
The word is prickly and sharp, and comes from the Latin aculeatus, which means sting, from the word acus, needle.shrewd tapering off somewhat
The word is prickly and sharp, and comes from the Latin aculeatus, which means sting, from the word acus, needle.shrewd tapering off somewhat
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Botanical Terms -adaptation
that which an organism can use to its full potential in a particular environmental zone while also fitting it generally.
that which an organism can use to its full potential in a particular environmental zone while also fitting it generally.
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Botanical Terms -Michel Adanson (1727–1806)
a French collector and botanist who served as a clerk on a commercial mission in Senegal and made numerous previously unidentified plant discoveries. He brought back a sizable collection of plants and seeds to France in the 1750s. Despite later discoveries that specimens of the baobab were more widely dispersed, he was the first European to describe the plant, which he had seen in West Africa. He calculated that the tree he observed was roughly 5000 years old; nevertheless, radiocarbon dating has verified that some specimens are 1000 years old, while less accurate techniques have calculated older ages for other specimens. In his honor, the baobab genus (*Adansonia) was named.
Adansonia is a genus of trees in the family *Bombacaceae, some species of which are pollinated by ants living inside of modified spines. The baobab (A. digitata) is well-known for its enormously enlarged trunk, which may grow to a height of 35 m and a circumference of 15 m. Some species swell, although not as much. Baobab offers food and medications for both humans and animals. There are nine species, which can be found in Madagascar, northwestern Australia, and the seasonal tropics of Africa.
a French collector and botanist who served as a clerk on a commercial mission in Senegal and made numerous previously unidentified plant discoveries. He brought back a sizable collection of plants and seeds to France in the 1750s. Despite later discoveries that specimens of the baobab were more widely dispersed, he was the first European to describe the plant, which he had seen in West Africa. He calculated that the tree he observed was roughly 5000 years old; nevertheless, radiocarbon dating has verified that some specimens are 1000 years old, while less accurate techniques have calculated older ages for other specimens. In his honor, the baobab genus (*Adansonia) was named.
Adansonia is a genus of trees in the family *Bombacaceae, some species of which are pollinated by ants living inside of modified spines. The baobab (A. digitata) is well-known for its enormously enlarged trunk, which may grow to a height of 35 m and a circumference of 15 m. Some species swell, although not as much. Baobab offers food and medications for both humans and animals. There are nine species, which can be found in Madagascar, northwestern Australia, and the seasonal tropics of Africa.