taxi-, tax-, taxo-, taxio-, -taxia, -taxis, -taxy, tact-, -tactic, -tactical, -tactics

Restrictions in a language on the permissible combinations of phonemes.

Phonotactics defines permissible syllable structure, consonant clusters, and vowel sequences by means of phonotactical constraints.

A directed response of a motile organism to color or a light pattern stimulus.

In biology, a response of an organism to a temporal change in light intensity:

Photophobotaxis can be explained by a cell or living thing moving towards the intensity of brilliance, termed as positive, or moves away from the source, termed as negative.

Of, pertaining to, or exhibiting phototaxis.

1. The movement of an organism in response to color or light pattern stimulus.
2. Taxis of an organism elicited in response to the source of a light stimulus.
3. In botany, the movement of a part of a plant toward or away from light sources.

The order or geometric principles of arrangement of leaves (or other lateral members; such as, florets of a composite flower, scales of a pine-cone, etc.) upon an axis or stem.

The principal kinds of phyllotaxis are

1. Cyclical or verticillate, in which a number of leaves (two or more) stand at the same level, forming a pair or whorl.
2. Spiral or alternate, in which each leaf stands singly, with its points of insertion forming a spiral (the genetic spiral) around the stem.

In the latter case, the phyllotaxis is expressed by a fraction denoting the angle (or portion of one turn of the spiral) between two successive leaves; thus, in a 25 phyllotaxis, there are five leaves in every two turns of the spiral.

1. The arrangement of the leaves on the stem.

The three common positions are alternate, opposite, and verticillate.

2. The principles governing leaf arrangement.

When spiral, often expressed quantitatively as the fraction of the circumference of the stem that separates two successive leaves.

The arrangement of leaves.

1. In botany, the condition whereby there are more than the usual number of flora whorls, as with "double" flowers.
2. Having more than the normal number of parts.

1. Relating to the regulation of the rate of respiration.
2. Concerning the regulation of the pulmonary respiration rate.

A directed response of a motile organism towards (positive) or away from (negative) dissolved gas; especially, carbon dioxide.

Positive phototaxis.

Positive aerotaxis: Prosaerotaxis is the movement of a life form, for example a bacterium, toward oxygen or air, and certainly not away from oxygen!

Positive chemotaxis.

Positive galvanotaxis.