Freeze frog program

Its breathing stops and there is no activity in its brain. In the spring, the frog begins the thawing process. Water flows back into cells, the heart restarts, blood flows again, the lungs take in air, and the brain becomes active.

The complete thawing process takes a few days to complete. Once defrosted, the frog is off to eat, mate, and start the process over again the next winter. Wood Frogs occur in the Ozark Highlands of Arkansas in the northwest and north-central part of the state. This finding could also help doctors more easily track the progression of nerve degeneration in the brain.

Rotello comes to this study having done plenty of work in the area of cell death, including in his doctoral and postdoctoral research. They caught the frogs in the Greene County area last spring, the season when the frogs call out to one another with a loud chorus. These students went out after dark to catch the frogs and then classified them by species and sex. Other students from these classes have helped maintain the frogs and their food supply, including current Bachelor of Science in biology students Carson Gehman, a senior from Hot Springs, South Dakota; Kristina Newell, a junior from Nazareth, Pennsylvania; Thomas Eagle, a junior from Galloway, Ohio; and Sawyer Williams, a junior from Mazomanie, Wisconsin.

The researchers cared for the frogs throughout the year, and then in January they used a sophisticated temperature- and humidity-controlled incubator to simulate the conditions of freezing and thawing.

These students went out after dark to catch the frogs, and then classified them by species and sex. Other students from these classes have helped maintain the frogs and their food supply, including current Bachelor of Science in biology students Carson Gehman, a senior from Hot Springs, South Dakota; Kristina Newell, a junior from Nazareth, Pennsylvania; Thomas Eagle, a junior from Galloway, Ohio; and Sawyer Williams, a junior from Mazomanie, Wisconsin.

The researchers cared for the frogs throughout the year, and then in January they used a sophisticated temperature- and humidity-controlled incubator to simulate the conditions of freezing and thawing. They compared the cells and frogs in various stages of freezing and thawing to find what makes freeze-tolerant frogs so unique.

Mendel and Paris noted that a better understanding of cell death would be useful beyond neurological diseases. For instance, researchers may be better able to kill targeted cancer cells, protect crops during cold snaps or respond to frostbite. Mendel and Paris added that Dr. Thomas Mach , vice president for academics, arranged funding for the incubator from his office, the department of science and mathematics and the school of pharmacy. Rotello notes early results are intriguing regarding the central control protein known as phosphorylated Akt and vascular endothelial tyrosine phosphatases.

The group hopes to have more detailed analysis and confirmed results by the end of the semester. Located in southwest Ohio, Cedarville University is an accredited, Christ-centered, Baptist institution with an enrollment of 4, undergraduate, graduate and online students in more than areas of study. Founded in , Cedarville is one of the largest private universities in Ohio, recognized nationally for its authentic Christian community, rigorous academic programs, including the Bachelor of Science in biology program , strong graduation and retention rates, accredited professional and health science offerings and high student engagement ranking.

For more information about the University, visit cedarville. Caption A : Dr. Mike Mendel and senior Bachelor of Science in biology student Kristina Newell with a wood frog, a type of frog that survives being completely frozen during winter hibernation.

Caption B : A wood frog, a type of frog that survives being completely frozen during winter hibernation.

Could there be a medical breakthrough from college research? Understanding Science. The Oracle of Omaha knows how to beat inflation. This difference has to do with how ice crystals form in the different substrates. At such cold temperatures, if the turtles come into contact with ice for any reason, that contact essentially seeds the crystallization process in the turtles and causes a chain reaction whereby the turtles freeze solid almost instantaneously.

In laboratory experiments with no outside ice to seed the turtle crystallization, hatchling Painted Turtles can supercool to C -4F before flash freezing occurs. While freezing solid at C 14F almost always causes turtle death, the hatchlings are tolerant of freezing at milder temperatures.

The same glucose that helps the turtles supercool also protects their tissues from damage caused by the freezing process. High concentrations of glucose between the cells draws water into the extracellular spaces so when freezing does occur, it occurs outside of the cells and the ice does not rupture the cells as it expands.

Consequently, the hatchlings can survive freezing to about -4C 25F. In this state, all but the liver and other vital organs freeze solid and can remain so for several days without causing harm to the turtles. Only a small handful of turtle species can freeze as hatchlings, and of those, only the Box Turtle Terrapene carolina can also freeze as an adult Box Turtles being the only species with freeze-tolerant hatchlings that overwinters on land as an adult.

The only other reptiles native to North America with some freezing ability are gartersnakes Thamnophis sp. Gartersnakes are capable of supercooling to about -5C 23F and can only survive in a frozen state only for about 10 hours or so. While this pales in comparison to abilities of the Painted Turtle, gartersnakes do not need to endure conditions nearly as extreme as those suffered by the turtles, in part because all gartersnakes, including neonates newborns , overwinter far enough below ground to avoid freezing temperatures.

Likely their tolerance of short periods below freezing is an evolved safeguard to protect against overnight frosts that might occur in the spring and fall when the snakes are above ground. This gives gartersnakes major advantages over other snakes and may explain why they range so much farther north than other species by roughly miles and can be seen mating while there is still snow on the ground. There are also a handful of amphibians with remarkable tolerance to freezing temperatures, and they make the freeze-tolerant reptiles look like amateurs.

The mechanism by which they survive freezing is very similar to that of hatchling turtles; they produce sugars that draw water out of their cells so that freezing occurs outside of cells rather than within.

In addition to glucose, the treefrogs also use glycogen as a cryoprotectant and Wood Frogs retain urea the frog equivalent to urine to aid in the process. During a freeze, frogs will appear from the outside to be entirely frozen.

Their skin and eyes will be rock hard and most of the fluid in their bodies will be solid, but as with the hatchling turtles, their liver and heart remain in a super-cooled state. The heart will cease to beat for the duration of the freeze, until the thawing process when something truly remarkable happens. Instead, the frogs thaw from the core outward, starting with organs that have the highest concentrations of sugary antifreeze. The heart starts beating and as each subsequent layer of tissue thaws blood flow is immediately restored until finally the skin and eyes soften.

The entire process just takes a couple hours and the frogs can resume normal body function immediately afterward. Freeze-tolerant frogs can typically survive lower temperatures and remain mostly frozen for longer periods of time than any reptile, with most of them capable of freezing to roughly -5C 23F or so for durations of up to a couple weeks.

Recently, however, researchers found that Wood Frogs in Alaska near the northern extent of their range can survive freezing to temperatures as low as C 0F and remain frozen for upwards of consecutive days, which is an order of magnitude longer than anyone had previously documented. Those Alaskan frogs also had muscle glucose concentrations approximately ten times higher compared to Wood Frogs studied in farther south, suggesting the degree to which Wood Frogs can survive cold temperatures might vary according to latitude, as is the case with some insects.

Throughout their range, however, air temperatures regularly fall far below that which the frogs can survive and frogs depend on insulation from snow cover to protect them from the harshest conditions.

At the end of winter, that same snow serves another valuable purpose to the frogs. Wood Frogs almost always breed and lay their eggs in vernal pools, which rely largely on snow melt as a water source in the spring. As temporary bodies of water that dry out by mid to late summer, vernal pools are free of fish that would prey upon breeding amphibians, their eggs, and their larva.

For that same reason, amphibians need to lay their eggs as early in the season as possible if the young are to survive long enough to mature before pools dry. Siberian Salamanders use glycogen as a cryoprotectant, as do the treefrogs discussed earlier.