Plant Morphogenesis: Growth, Differentiation and Communication

Plant morphogenesis&#8212;the development of a plant&#8217;s form and structure&#8212;involves several overlapping developmental processes, including growth and cell differentiation. Precursor cells differentiate into specific cell types, which are organized into the tissues and organ systems that make up the functional plant.<br /><br />Plant growth and cell differentiation are under complex hormonal control. Plant hormones regulate gene expression, often in response to environmental stimuli. For...

Other Algae

The group Stramenopiles include some phototrophic microorganisms. Members of this group possess flagella covered in numerous short, hairlike extensions, a feature that inspired the group's name, derived from the Latin words for "straw" and "hair." Some of the main categories of Stramenopiles include diatoms, golden algae, and brown algae.Diatoms are unicellular, photosynthetic eukaryotes, with over 200 known genera. They play a key role in the planktonic communities of both marine and...

Diversity of Protists III

Rhizaria are a diverse group of unicellular protists characterized by their threadlike cytoplasmic extensions known as pseudopodia. These structures aid in both locomotion and feeding, giving Rhizaria an amoeboid appearance. Their amoeboid morphology once led to taxonomic confusion, but molecular phylogenetics has clarified their evolutionary placement and emphasized their shared use of pseudopodia despite divergent lineages.This clade comprises diverse lineages such as Chlorarachniophyta,...

Keystone Species in the Ecosystem

Measures of species biodiversity, such as richness (i.e., the number of species present) and evenness (i.e., their relative abundance), describe an ecological community&rsquo;s structure. Many factors affect community structure, including abiotic factors (e.g., sunlight and nutrients), disturbances (e.g., fire or flood), species interactions (e.g., predation or competition), and chance events (e.g., foreign species invasion). Certain species&mdash;such as keystone species&mdash;also play a...

Seedless Vascular Plants: Monilophytes and Lycophytes

Seedless Vascular Plants Were the First Tall Plants on Earth<br /><br />Today, seedless vascular plants are represented by monilophytes and lycophytes. Ferns&mdash;the most common seedless vascular plants&mdash;are monilophytes. Whisk ferns (and their relatives) and horsetails are also monilophytes. Lycophytes include club mosses, spikemosses, and quillworts&mdash;none of which are true mosses.<br /><br />Unlike nonvascular plants, vascular plants&mdash;including seedless vascular plants&mdash;have an extensive...

Rhizobacteria and Mycorhizae in Plant Nutrition

Plants have the impressive ability to create their own food through photosynthesis. However, plants often require assistance from organisms in the soil to acquire the nutrients they need to function correctly. Both bacteria and fungi have evolved symbiotic relationships with plants that help the species to thrive in a wide variety of environments.<br /><br />The collective bacteria residing in and around plant roots are termed the rhizosphere. These soil-dwelling bacterial species are incredibly diverse....