皮皮学，免费搜题
登录
搜题
【简答题】
只有那些有过类似经历的人,才能够完全理解这一点。(live through)
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【单选题】如图所示,弹簧测力计下挂着铁块P,其正下方的水平地面上放着一块条形磁铁Q,P和Q均处于静止状态。已知P和Q的重力分别为G和3G,若弹簧测力计的示数为2G,则下列说法正确的是( )
A.
P对弹簧测力计的拉力等于G
B.
P对Q的吸引力和地面对Q的支持力大小分别为G和2G
C.
P在两个力的作用下处于平衡状态
D.
弹簧测力计对P的拉力和Q对P的吸引力是一对平衡力,大小均为2G
【单选题】如图所示,弹簧测力计下挂着铁块P,其正下方的水平地面上放着一块条形磁铁Q,P和Q均处于静止状态。已知P和Q的重力分别为G和3G,若弹簧测力计的示数为2G,则下列说法正确的是
A.
P对弹簧测力计的拉力大小为G
B.
P对Q的吸引力和Q对P的吸引力是一对平衡力,大小均为G
C.
P对Q的吸引力和地面对Q的支持力大小分别为G和2G
D.
弹簧测力计对P的拉力和Q对P的吸引力是一对平衡力,大小均为2G
【单选题】What is true about B1 cells
A.
It is usually called B cell
B.
It's the majority of B cells
C.
Primary cell of specific humoral immunity
D.
self-renewal
E.
high frequency somatic mutation
【多选题】How do cell-surface receptors relay extracellular signals via intracellular signaling pathways?
A.
The majority of extracellular signal molecules are proteins, peptides, or small, hydrophilic molecules that bind to cell-surface receptors that span the plasma membrane. Transmembrane receptors detect a signal on the outside and relay the message, in a new form, across the membrane into the interior of the cell.
B.
The receptor protein performs the primary step in signal transduction: it recognizes the extracellular signal and generates new intracellular signals in response.
C.
The resulting intracellular signaling process usually works like a molecular relay race, in which the message is passed “downstream” from one intracellular signaling molecule to another, each activating or generating the next signaling molecule in the pathway, until a metabolic enzyme is kicked into action, the cytoskeleton is tweaked into a new configuration, or a gene is switched on or off.
D.
This final outcome is called the response of the cell.
【单选题】如图所示,弹簧测力计下挂着铁块 P,其正下方的水平地面上放着一块条形磁铁 Q,P 和 Q 均处于静止状态.已知 P 和 Q 的重力分别为 G 和 3G,若弹簧测力计的示数为 2G,则下列说法正确的是( )
A.
P 对弹簧测力计的拉力大小为 G
B.
P 对 Q 的吸引力和地面对 Q 的支持力大小分别为 G 和 2G
C.
P 对 Q 的吸引力和 Q 对 P 的吸引力是一对平衡力,大小均为 G
D.
弹簧测力计对 P 的拉力和 Q 对 P 的吸引力是一对平衡力,大小分别均为 2G
【简答题】从A、B、C、D中选择最恰当的选项填进文章中去，你会读到一个有意思的故事。 Do you like pop music? Most people do. One of the best 1 on the music scene is the New Ocean Waves. In the 2 twelve months, they've had three major 3 and made a h...
相关题目：