[The resistance of Amoeba proteus amebae with different levels of nuclear DNA to the action of high temperature and ethyl alcohol].

Thermotolerance and resistance to ethyl alcohol were investigated in Amoeba proteus of polyploid series. Thermoresistance of these amoebae was determined by measuring the mean time of survival at the lethal temperature (43 degrees C). The resistance to ethyl alcohol was estimated by the mean percentage of individuals that survived following a 5-minute treatment with 7.5% ethyl alcohol. Neither thermotolerance, nor ethyl alcohol resistance were found to depend on the amount of nuclear DNA. It was also established that colchicine did not induce a hereditary instability of thermoresistance in amoebae.