糖原合成的关键酶是（）
A.葡萄糖氧化酶
B.果糖-1，6-二磷酸酶
C.丙酮酸脱氢酶
D.乳酸脱氢酶
E.糖原合成酶
参考答案：E
选择表达正确的句子。
( ) 1. A. She is putting her pencils in her pencil case.
B. She is put her pencils in her pencil case.
( ) 2. A. He reading a book.
B. He is reading a book.
( ) 3. A. Where is Mr. Wood?
B. Where are Mr. Wood?
( ) 4. A. He is in library.
B. He is in the library.
在如图所示的电路中，R1、R2、R3和R4皆为定值电阻，R为滑动变阻器，电源的电动势为E，内阻为r．设电流表A的读数为I，电压表V的读数为U．当滑动变阻器R的滑动头向图中b端移动时，（ ）
A．I变大，U变小
B．I变大，U变大
C．I变小，U变大
D．I变小，U变小
