Organelles Involved in Photosynthesis | Sciencing

Polar forests reappeared in the Eocene after the , and the Eocene’s was the Cenozoic’s warmest time and . Not only did alligators live near the North Pole, but the continents and oceans hosted an abundance and diversity of life that Earth may have not seen before or since. That ten million year period ended as Earth began cooling off and headed toward the current ice age, and it has been called the original Paradise Lost. One way that methane has been implicated in those hot times is that leaves have , which regulate the air they take in to obtain carbon dioxide and oxygen, needed for photosynthesis and respiration. Plants also lose water vapor through their stomata, so balancing gas input needs against water losses are key stomata functions, and it is thought that in periods of high carbon dioxide concentration, . Scientists can count stomata density in fossil leaves, which led some scientists to conclude that carbon dioxide levels were not high enough to produce the PETM, so that produced the PETM and , and the controversy and research continues.

In eukaryotic cells these reactions occur in the organelle known ..

Only eukaryote cells (plants, animals, fungi, protists) contain membrane-bound organelles.

In what cellular organelle does photosynthesis ..

Another energy-related activity probably appeared on a large scale during the reign of dinosaurs: . Although territoriality , , , , and today, it is most common among birds and mammals. Territoriality is primarily about preserving an animal’s energy base from competition, and it is usually a behavior oriented toward others of the same species, which would eat the same food resources and mate with the same potential partners. Just as what scientists call , territorial behavior may go all the way back to the . But the social behaviors apparent in dinosaurs probably also meant territorial behavior, and probably on a scale never experienced before on Earth. Even the suspected display function of implies territorial behavior. All are territorial, and human political units such as are little more than ape territoriality writ large, as peoples protect their energy and mating bases. In light of the (with its apotheosis in the peacock, although, as usual, ), and the phenomenon perhaps goes , along with the discovery of dinosaurian mass nesting sites, herd behaviors, and the like, many scientists believe that .

The cell is the basic unit of a living organism

Because of the stupendous energy demands of flight, birds not only have the superior air sac system for breathing, but their , the cell’s energy-generation centers, are far more efficient than mammalian mitochondria. Parrots in captivity can , scientists have noted an , and scientists may discover that wild albatrosses live to be 100 or more, when their tagging programs get that old. The may explain bird longevity, as the efficient mitochondria of birds . The theory is controversial and will be for many years, but I think that an engine analogy can help. A bird is a piece of high-performance biological technology, and when operating at peak output it puts all land-bound animals to shame. But a bird’s metabolism is usually in its slack state, only maximized during flight. Simply put, a bird has a great energy capacity that is rarely used to its fullest. It is like a high-performance engine that rarely runs near its . Such engines will last far longer than those regularly running near redline. High-performance technology that usually “loafs” in its slack state and is rarely taxed is expensive and long-lasting. The increased investment in superior technology allows for high performance and long life. High-quality technology is more economical in the long run, if the initial investment can be afforded.

What cell organelle is used in photosynthesis

works for animals that are no more than a couple of millimeters thick, but for larger animals a respiration system was necessary. The rise of the arthropods has been an enduring problem for paleobiologists. Why was the arthropod so successful, particularly in the beginning? Segmented animals dominated Cambrian seas, and segmentation provides for repeated features. Segments obviously became important for locomotion but, for arthropods, segmentation appears to have conferred the more important advantage of distributed oxygen absorption. Each trilobite leg had an attached gill, and leg motion constantly drew fresh oxygenated water over each gill. Arthropods never developed the kinds of lungs that vertebrates have, or the pump gills of fish and other aquatic animals. Early arthropods breathed by moving their legs. Peter Ward’s recent hypothesis is that segments were first used for respiration, to provide a large gill surface area, and using the segments for locomotion came later. For trilobites, the same functionality that pushed water over gills was also coopted for food intake. Also, the leg-mounted gill was necessary because of an arthropod’s body armor; oxygen could not be absorbed through tough exoskeletons.

Organelle Definition; Cell Organelles;

Eyes began with that captured photons that through chemical cycles in a new kind of specialized cell: the nerve cell. Neurons are energy hogs and “high-tension electric lines” in animals. Human brain tissue uses ten times the energy that non-organ tissues elsewhere in the body do. The first eyes probably only detected light, and perhaps even infrared light, so that from life-giving/destroying volcanic vents, for instance. Hydrothermal vent shrimp today , which can be likened to naked retinas. The development of an eye with a lens was not a great evolutionary leap from rudimentary eyes, and a recent calculation shows how eyes with lenses could have developed from scratch in about a half-million years of evolution. may have had the first precursors to eyes. Once the eye evolved, its benefit was overwhelmingly obvious, and virtually all animals that live where vision would help them have eyes. Animals that adopted subterranean existences . It is thought today that the development of eyes was a key innovation in the arms race that would soon characterize the eon of animals, and might have even triggered it. The gene is common to all animals with eyes. As , that gene supports the widely accepted idea that . The purpose of all senses is to detect environmental information, which is in turn processed by the brain. Even brainless plants can detect light and modify their behavior, such as .

What organelles and structures are associated in cell to cell ..

So far in this essay, mammals have received scant attention, but the mammals’ development before the Cenozoic is important for understanding their rise to dominance. The , called , first , about 260 mya, and they had key mammalian characteristics. Their jaws and teeth were markedly different from those of other reptiles; their teeth were specialized for more thorough chewing, which extracts more energy from food, and that was likely a key aspect of success more than 100 million years later. Cynodonts also developed a secondary palate so that they could chew and breathe at the same time, which was more energy efficient. Cynodonts eventually ceased the reptilian practice of continually growing and shedding teeth, and their specialized and precisely fitted teeth rarely changed. Mammals replace their teeth a . Along with tooth changes, jawbones changed roles. Fewer and stronger bones anchored the jaw, which allowed for stronger jaw musculature and led to the mammalian (clench your teeth and you can feel your masseter muscle). Bones previously anchoring the jaw were no longer needed and . The jaw’s rearrangement led to the most auspicious proto-mammalian development: . Mammals had relatively large brains from the very beginning and it was probably initially . Mammals are the only animals with a , which eventually led to human intelligence. As dinosaurian dominance drove mammals to the margins, where they lived underground and emerged to feed at night, mammals needed improved senses to survive, and auditory and olfactory senses heightened, as did the mammalian sense of touch. Increased processing of stimuli required a larger brain, and . In humans, only livers use more energy than brains. Cynodonts also had , which suggest that they were warm-blooded. Soon after the Permian extinction, a cynodont appeared that may have ; it was another respiratory innovation that served it well in those low-oxygen times, functioning like pump gills in aquatic environments.