auxin

American  

[awk-sin] / ˈɔk sɪn /

noun

Biochemistry.

1. a class of substances that in minute amounts regulate or modify the growth of plants, especially root formation, bud growth, and fruit and leaf drop.

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auxin British  

/ ˈɔːksɪn /

noun

1. any of various plant hormones, such as indoleacetic acid, that promote growth and control fruit and flower development. Synthetic auxins are widely used in agriculture and horticulture

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auxin Scientific  

/ ôk′sĭn /

1. Any of various hormones or similar substances that promote and regulate the growth and development of plants. Auxins are produced in the meristem of shoot tips and move down the plant, causing various effects. Auxins cause the cells below the shoot apex to expand or elongate, and this (rather than cell division) is what causes the plant to increase in height. In woody plants, auxins also stimulate cell division in the cambium, which produces vascular tissue. Auxins inhibit the growth of lateral buds so that the plant grows upwards more than outwards. They can be produced artificially in laboratories for such purposes as speeding plant growth and regulating how fast fruit will ripen.

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Other Word Forms

• auxinic adjective

Etymology

Origin of auxin

First recorded in 1930–35; aux- + -in ²

Example Sentences

"Craig was the one to really dig in, to confirm that this gene carries the plant hormone auxin, and it absolutely controls size in corn."

From Science Daily

At the same time, they made the ARF7 protein luminescent, which is the protein that controls the auxin responses and which the plant cell's garbage collectors clean up to provide optimal root growth.

From Science Daily

Their findings revealed that the levels of active auxins, cytokinins, ABA, and inactive GAs increased as cells differentiated to form organs, highlighting their role in plant cell differentiation and organogenesis.

From Science Daily

Plant hormones like auxin and cytokinin have been connected to the angle of root growth in the past, but the mechanisms of that connection have remained poorly understood.

From Science Daily

Pinching removes a growth hormone produced in the stem tip called auxin.

From Seattle Times