Introduction to Cellular Respiration

Stages of Cellular Respiration

You already know the equation for aerobic respiration:

Mass extinction events can seem quite capricious as to what species live or die. generally outcompeted their ancestral for hundreds of millions of years. Ammonoids were lightweight versions of nautiloids, and they often thrived in shallow waters while nautiloids were banished to deep waters. Both dwindled over time, as they were outcompeted by new kinds of marine denizens. In the and mass extinctions, deep-water animals generally suffered more than surface dwellers did, but the nautiloids’ superior respiration system still saw them survive. Also, nautiloids laid relatively few eggs that took about a year to hatch, while ammonoids laid more eggs that hatched faster. However, the asteroid-induced Cretaceous mass extinction annihilated nearly all surface life while the deep-water animals fared better, and nautiloid embryos that rode out the storm in their eggs were survivors. The Cretaceous extinction while and comprise another group of living fossils, although that status is disputed in 2014. was about the only land animal of significance that survived the Permian extinction and it dominated the early Triassic landmass as no animal ever has. It comprised about 95% of all land animals. Why , which was like a reptilian sheep? Nobody , but it may have been the luck of the draw. Perhaps relatively few bedraggled individuals existed in some survival enclave until the catastrophe was finished, and then they quickly bred unimpeded until , for the most spectacular species radiation of all time, at least until humans arrived on the evolutionary scene.

This energy used (lost) is attributed to cellular respiration.

Allows for more energetic respiration than anaerobic respiration.

guinea-pig 60 Hz, 10 mT; 10 - 110-min No effect on respiration (1971) brain exposures (oxidative phosphorylation) mitochondria in vitro Riesen et al.

Conversely, anaerobic respiration does not require oxygen to transfer energy.

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.

If insufficient oxygen is supplied anaerobic respiration takes place in muscles.

cellular respiration and photosynthesis in regard to the ..

In a chronic study involving exposure of F344 rats to 0, 49, 147, or 441 mg/m3 and of BDF1 mice to 0, 25, 147, or 441 mg/m3, 6 h/day, 5 days/week, for 104 weeks, ossification of the nasal turbinates (rats) and nasal septum (mice) and atrophy and respiratory metaplasia of the olfactory epithelium were reported at all exposure concentrations (Yamamoto, 1996; Yamamoto et al., 2002). In spite of the overt toxicity and increased cell proliferation in the nose, no nasal tumours were noted in this or any of the other chronic studies.

the synthesis of ATP in either cellular respiration or photosynthesis

Since we measured nonstructural carbohydrates every 2 hr during a 24-hr period, I know what happens to nonstructural carbohydrate levels at night when plant respiration continues and photosynthesis stops, they decline rapidly.

Factors Affecting Aerobic Respiration: 8 Factors | Plants

F344 rats and BDF1 mice (10 per sex per species per concentration) were exposed at 0, 2.5, 5, 10, 20, or 40 g/m3, 6 h/day, 5 days/week, for 2 weeks. Rats survived at up to 5 g/m3, but all died within 2 days at 10 g/m3 and above. The female mice survived exposure at 2.5 g/m3, but deaths occurred (from day 4 onwards) at 5 g/m3. Only two male mice survived, one at 2.5 g/m3 and one at 5 g/m3. Dead rats showed lung congestion and inflammation, believed to arise as a result of cardiovascular toxicity. Deaths in mice were ascribed to necrosis of the kidney proximal tubules (males) and centrilobular necrosis of the liver (females). Surviving rats showed vacuolic changes in the proximal kidney tubules and the central area of the liver, as well as desquamation, atrophy, and disarrangement of the olfactory epithelium and oedema of the lamina propria of the nasal cavity. Surviving male mice had necrosis in the kidney proximal tubules, slight swelling and vacuolic change in the liver, and atrophy and respiratory metaplasia in the olfactory epithelium. The surviving female mice showed necrosis and vacuolic changes in the liver and necrosis and disarrangement of the olfactory and respiratory epithelia, but no kidney changes (Kasai et al., 2002).