The movement of an organism, or part of an organism, in response to a light stimulus, usually toward or away from it.

The process of introducing a phosphate group on to a protein.

The unidirectional movement of auxin from the apex to base of an organ, including the shoot, leaf, primary root, or lateral root.

The process of introducing a phosphate group on to a protein.

The process whose specific outcome is the progression of the pollen grain over time, from its formation to the mature structure. The process begins with the meiosis of the microsporocyte to form four haploid microspores. The nucleus of each microspore then divides by mitosis to form a two-celled organism, the pollen grain, that contains a tube cell as well as a smaller generative cell. The pollen grain is surrounded by an elaborate cell wall. In some species, the generative cell immediately divides again to give a pair of sperm cells. In most flowering plants, however this division takes place later, in the tube that develops when a pollen grain germinates.

The orientation of plant parts under the stimulation of gravity.

The process in which a cell irreversibly increases in size in one

Growth of pollen via tip extension of the intine wall.

The process in which a protrusion or bulge is formed at the site of plant root hair outgrowth.

The cellular component assembly process of forming pollen apertures, areas where exine is reduced or absent, in the pollen cell wall.

Any process that modulates the frequency, rate or extent of establishment of cell polarity.

Any process that stops, prevents, or reduces the frequency, rate or extent of programmed cell death, cell death resulting from activation of endogenous cellular processes.

The process whose specific outcome is the progression of a root hair cell over time, from its formation to the mature state.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.

All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.

The region of the plasma membrane located at the basal end of the cell. Often used in reference to animal polarized epithelial membranes, where the basal membrane is the part attached to the extracellular matrix, or in plant cells, where the basal membrane is defined with respect to the zygotic axis.

The part of a cell encompassing the cell cortex, the plasma membrane, and any external encapsulating structures.

A small, dense body one or more of which are present in the nucleus of eukaryotic cells. It is rich in RNA and protein, is not bounded by a limiting membrane, and is not seen during mitosis. Its prime function is the transcription of the nucleolar DNA into 45S ribosomal-precursor RNA, the processing of this RNA into 5.8S, 18S, and 28S components of ribosomal RNA, and the association of these components with 5S RNA and proteins synthesized outside the nucleolus. This association results in the formation of ribonucleoprotein precursors; these pass into the cytoplasm and mature into the 40S and 60S subunits of the ribosome.