Plant Growth

• Undifferentiated cells in the meristems of plants allow indeterminate growth
• Mitosis and cell division in the shoot apex provide cells needed for extension of the stem and development of leaves
• Plant hormones control growth in the shoot apex
• Plant shoots respond to the environment by tropisms
• Auxin efflux pumps can set up concentration gradients of auxin in plant tissue
• Auxin influences cell growth rates by changing the pattern of gene expression