一、选择题:- 一上下列说法正确的是- A_、蛙的胚胎发育属于变态发育:_ 玖红薯通过块根进行营养繁殖护 ·c。变态发育的生物都是XY型性别决定; 环彗幸菜的球l糊剑本有叶细触」受精卵分李笔了三次。 2.下列说法正确的是_ A、给病人输氧时,要在纯氧中棍人少量co汽体 来维持呼吸中 First, the multiple-choice questions: - One of the following statements is correct - A_, frog’s embryonic development is perverted development: _ 玖 玖 玖 玖 玖 玖 sweet potato through vegetative propagation protection c. The metamorphosis developing organisms are all XY-type sex determinations; the balls of the luckily fortunate dish have a leaf touch and the fertilized egg is divided into three strokes. 2. The following statement is correct _ A, when oxygen is given to the patient, a small amount of co gas should be used to maintain the breath in the oxygen.