Information:  - Spirogyra (common names include water silk, mermaid's tresses, and blanket weed) is a genus of filamentous charophyte green algae of the order Zygnematales, named for the helical or spiral arrangement of the chloroplasts that is diagnostic of the genus. It is commonly found in freshwater areas, and there are more than 400 species of "Spirogyra" in the world. "Spirogyra" measures approximately 10 to 100 m in width and may grow to several centimeters in length.  - In vascular plants, phloem is the living tissue that transports the soluble organic compounds made during photosynthesis (known as photosynthate), in particular the sugar sucrose, to all parts of the plant where needed. This transport process is called translocation. In trees, the phloem is the innermost layer of the bark, hence the name, derived from the Greek word ("phloios") meaning "bark".  - Chlamydomonas is a genus of green algae consisting of unicellular flagellates, found in stagnant water and on damp soil, in freshwater, seawater, and even in snow as "snow algae" "Chlamydomonas" is used as a model organism for molecular biology, especially studies of flagellar motility and chloroplast dynamics, biogeneses, and genetics. One of the many striking features of "Chlamydomonas" is that it contains ion channels, (channelrhodopsins), that are directly activated by light. Some regulatory systems of "Chlamydomonas" are more complex than their homologs in Gymnosperms, with evolutionarily related regulatory proteins being larger and containing additional domains.  - In taxonomy, the Volvocales, also known as Chlamydomonadales, are an order of flagellate or pseudociliate green algae, specifically of the Chlorophyceae. Volvocales can form planar or spherical colonies. These vary from "Gonium" (4 to 32 cells) up to "Volvox" (500 cells or more). Each cell has two flagella, and is similar in appearance to "Chlamydomonas", with the flagella throughout the colony moving in coordination.  - Kelps are large seaweeds (algae) belonging to the brown algae (Phaeophyceae) in the order Laminariales. There are about 30 different genera.  - Gonium is a genus of colonial algae , a member of the order Volvocales . Typical colonies have 4 to 16 cells , all the same size , arranged in a flat plate , with no anterior - posterior differentiation . In a colony of 16 cells , four are in the center , and the other 12 are on the four sides , three each . A description by G.M. Smith ( 1920 , p. 94 ) : Gonium Mueller 1773 : Colonies of 4 - 8 - 16 cells arranged in a flat quadrangular plate and embedded in a common gelatinous matrix or connected by broad gelatinous strands . Cells ovoid to pyriform , with a single cup - shaped chloroplast containing one pyrenoid . Each cell with two cilia of equal length , contractile vacuoles at the base of the cilia , and an eyespot . Four - and eight - celled colonies with the cilia on the same side ; sixteencelled colonies with the four central cells having their cilia on the same side and the twelve marginal cells with radially arranged cilia . Asexual reproduction by simultaneous division of all cells in the colony to form autocolonies , or by a formation of 2 - 4 zoospores in each cell .  - A flagellate is a cell or organism with one or more whip-like organelles called flagella. The word "flagellate" also describes a particular construction (or level of organization) characteristic of many protists (eukaryotic organisms) and their means of motion. The term presently does not imply any specific relationship or classification of the organisms that possess flagellae. However, the term "flagellate" is included in other terms (such as "dinoflagellate" and "choanoflagellata") which are more formally characterized.  - The Chlorophyceae are one of the classes of green algae, distinguished mainly on the basis of ultrastructural morphology. For example, the chlorophycean CW clade, and chlorophycean DO clade, are defined by the arrangement of their flagella. Members of the CW clade have flagella that are displaced in a "clockwise" (CW, 17 o'clock) direction e.g. Chlamydomonadales. Members of the DO clade have flagella that are "directly opposed" (DO, 126 o'clock) e.g. Sphaeropleales. They are usually green due to the dominance of pigments chlorophyll a and chlorophyll b. The chloroplast may be discoid, plate-like, reticulate, cup-shaped, spiral or ribbon shaped in different species. Most of the members have one or more storage bodies called pyrenoids located in the chloroplast. Pyrenoids contain protein besides starch. Some algae may store food in the form of oil droplets. Green algae usually have a rigid cell wall made up of an inner layer of cellulose and outer layer of pectose.  - Chlorella is a genus of single-cell green algae belonging to the phylum Chlorophyta. It is spherical in shape, about 2 to 10 m in diameter, and is without flagella. "Chlorella" contains the green photosynthetic pigments chlorophyll-a and -b in its chloroplast. Through photosynthesis, it multiplies rapidly, requiring only carbon dioxide, water, sunlight, and a small amount of minerals to reproduce.  - Charophyta is a division of freshwater green algae. The terrestrial plants, the Embryophyta emerged within Charophyta, with the class Zygnematophyceae as a sister group. In some charophyte groups, such as Zygnematophyceae or conjugating green algae, flagellae are absent and sexual reproduction does not involve free-swimming flagellate sperm. Flagellate sperm, however, are found in stoneworts (Charales) and Coleochaetales, orders of parenchymatous charophytes that are the closest relatives of the land plants, where flagellate sperm are also present in all except the conifers and flowering plants. Fossil stoneworts of Devonian age that are similar to those of the present day have been described from the Rhynie chert of Scotland.  - In biology, an organism is any contiguous living system, such as an animal, plant, fungus, archaeon, or bacterium. All known types of organisms are capable of some degree of response to stimuli, reproduction, growth and development and homeostasis. An organism consists of one or more cells; when it has one cell it is known as a unicellular organism; and when it has more than one it is known as a multicellular organism. Most unicellular organisms are of microscopic scale and are thus loosely described as microorganisms. Humans are multicellular organisms composed of many trillions of cells grouped into specialized tissues and organs.  - Algae (singular "alga" ) is an informal term for a large, diverse group of photosynthetic organisms which are not necessarily closely related, and is thus polyphyletic. Included organisms range from unicellular genera, such as "Chlorella" and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to 50 m in length. Most are aquatic and autotrophic and lack many of the distinct cell and tissue types, such as stomata, xylem, and phloem, which are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the Charophyta, a division of green algae which includes, for example, "Spirogyra" and the stoneworts.  - Xylem is one of the two types of transport tissue in vascular plants, phloem being the other. The basic function of xylem is to transport water from roots to shoots and leaves, but it also transports some nutrients. The word "xylem" is derived from the Greek word  ("xylon"), meaning "wood"; the best-known xylem tissue is wood, though it is found throughout the plant.  - Volvox is a polyphyletic genus of chlorophyte green algae in the family Volvocaceae. It forms spherical colonies of up to 50,000 cells. They live in a variety of freshwater habitats, and were first reported by Antonie van Leeuwenhoek in 1700. "Volvox" diverged from unicellular ancestors approximately .    Given the information, choose the subject and object entities that have the relation of 'parent taxon'.
gonium , volvocaceae