Why do all plants contain at least some green on them? How do plants DEEP in the ocean get energy to grow?

Question

Obviously....there are probably some plants that I don't know of that don't have any green, but what causes most plants to have the color green on it, and what causes plants not to be green at all?

Also, how do plants WAY deep on ocean floors get energy to create food for themselves and such? Also, why don't those underwater plants drown, like regular land plants?

Answer 1

Wow, someone asking a question that does not sound like a homework problem!

There are some plants that are not green, but they are rare. The green is a chemical called chlorophyll. This chemical helps plants capture the energy of the sun and use it to make food. Plants take energy from the sun + water + carbon dioxide and turn it into sugar and oxygen. This process is called photosynthesis. Chlorophyll is the most efficient chemical plants have discovered to capture sunlight so almost all plants use it. There are some other chemicals, called accessory pigments, that can also capture sunlight but not as well;they are generally red.

There are no plants deep in the ocean. There has to at least be some sunlight to have plants.

Land plants drown when their roots are unable to get enough oxygen at night because the air has been pushed out of the soil. Seaweeds do have roots that go deep into the soil. They just have anchors that stick to rocks. They get bother thier nutrients and oxygen through their leaves.

Answer 2

Most plants are green because most plants use chlorophyll and that itself is green.  If a plant doesn't have chlorophyll then it won't be green.

Many plants at the bottom of the ocean are not green and don’t use chlorophyll.  Some plants in shallow water do, but if they live more than 25 meters below the surface then the amount of sunlight that reaches them is so minor that they can’t rely on chlorophyll.  They need some other energy source.

Hot Smokers are volcanic vents at the bottom of the ocean and a lot of plants and animal life develops around them using that energy to live.  Otherwise the bottom of the ocean is almost a desert, in fact it has less life than many deserts because the only source of food is the dead and decaying bodies that parts that have fallen from the surface.

Corals are small animals that act like plants.  Coral reefs are built (literally) on the bones of the coral.  They are the home for a lot of plants and animals.  Most of them are filter feeders; they pull the water in and filter out plankton and other nutrients.  A few plants are able to survive this way.

Plants don’t drown for the same reason fish don’t drown, they pull the water in extract what they need and expel it.

According to Wikipedia:  

"Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. Its name is derived from Greek: chloros = green and phyllon = leaf. Chlorophyll absorbs light most strongly in the blue and red but poorly in the green portions of the electromagnetic spectrum, hence the green color of chlorophyll-containing tissues like plant leaves."

According to Wikipedia:  

"Plant life is relatively rare undersea. Most of the niche occupied by sub plants on land is actually occupied by macroscopic algae in the ocean, such as Sargassum and kelp which are commonly known as seaweeds. The non algae plants that do survive in the sea are often found in shallow waters, such as the seagrasses (examples of which are eelgrass, Zostera, and turtle grass, Thalassia). These plants have adapted to the high salinity of the ocean environment. The intertidal zone is also a good place to find plant life in the sea, where mangroves or cordgrass or beach grass might grow. Sea kelp is very important to small sea creatures because the creatures can hide from predators."

According to Wikipedia:

"A hydrothermal vent is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, areas where tectonic plates are moving apart, ocean basins, and hotspots...

Relative to the majority of the deep sea, the areas around submarine hydrothermal vents are biologically more productive, often hosting complex communities fueled by the chemicals dissolved in the vent fluids. Chemosynthetic archaea form the base of the food chain, supporting diverse organisms, including giant tube worms, clams, and shrimp...

Life, as most people understand it, is driven by the sun, but deep sea organisms have no access to sunlight, so they must depend on nutrients found in the dusty chemical deposits and hydrothermal fluids they live in. Previously, marine biologists assumed that vent organisms were dependent on a "rain" of detritus from the upper levels of the ocean, like deep sea organisms are. This would leave them dependent on plant life and thus the sun. Some hydrothermal vent organisms do consume this "rain," but with only such a system, life forms would be very sparse. Compared to the surrounding sea floor, however, hydrothermal vent zones have a density of organisms 10,000 to 100,000 times greater.

Hydrothermal vent communities are able to sustain such vast amounts of life because vent organisms depend on chemosynthetic bacteria for food. The water that comes out of the hydrothermal vent is rich in dissolved minerals and supports a large population of chemoautotrophic bacteria. These bacteria use sulfur compounds, particularly hydrogen sulfide, a chemical highly toxic to most known organisms, to produce organic material through the process of chemosynthesis.

The ecosystem so formed is reliant upon the continued existence of the hydrothermal vent field as the primary source of energy, which differs from most surface life on Earth which is based on solar energy. However, although it is often said that these communities exist independently of the sun, some of the organisms are actually dependent upon oxygen produced by photosynthetic organisms. Others are anaerobic as was the earliest life."