Which of the following statements is false?A. Oxygenated and deoxygenated blood are mixed in the circulatory system of fishes. B.The fish heart consists of a single atrium and a single ventricle. C.Blood flowing to the body tissues of fishes is at a lower pressure than the blood entering the gills. D.Blood flows in a single circuit in fishes. E.None of the answer options is false.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

enzyme speed up the reactions

some inherited genetic mutations can be good for the offspring, so the answer is different genetic mutations cause many forms of cancer.

answer///unconditioned stimulus;