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【单选题】向日葵和番茄都能产生果实和种子，向日葵的果实就是平时我们吃的“瓜子”。在上述两种植物开花期间，遇到了连续的阴雨天，影响了植物的授粉。管理人员及时喷洒了一定浓度的生长素。下列叙述正确的是 [ ]
A.
两种植物都能形成无子果实，产量均未受影响
B.
番茄形成无子果实，产量未受影响；向日葵形成无子果实，产量下降
C.
两种植物都能形成无子果实，产量下降
D.
番茄形成有子果实，产量上升；向日葵不能形成无子果实
【单选题】向日葵和番茄都能产生果实和种子，向日葵的果实就是平时我们吃的“瓜子”。在上述两种植物开花期间，遇到了连续的阴雨天，影响了植物的授粉。管理人员及时喷洒了一定浓度的生长素。下列叙述正确的是 [ ]
A.
两种植物都能形成无子果实，产量均未受影响
B.
番茄形成无子果实，产量未受影响；向日葵形成无子果实，产量下降
C.
两种植物都能形成无子果实，产量下降
D.
番茄形成有子果实，产量上升；向日葵不能形成无子果实
【单选题】A remarkable variety of insects live in this planet. More species of insects exist than all other animal species together. Insects have survived on earth for more than 300 million years, and may posse...
A.
strong, hard but flexible shell covers their soft organs and is resistant to chemicals, water and physical impact. Their wings give them the option of flying away from erous situations or toward food or mates. Also, insects have an enormous reproductive capacity: An African ant queen can lay as many as 43,000 eggs a day.Another reason for their success is the strategy of protective color. An insect may be right before our eyes, but nearly invisible because it is cleverly disguised like a green leaf, lump of brown soil, gray lichen (青苔), a seed or some other natural object. Some insects use bright, bold colors to send warning signals that they taste bad, sting or are poison. Others have wing patterns that look like the eyes of a huge predator, confusing their enemies. Some insects also imitate bitter-tasting insects; hungry enemies are fooled into avoiding them.
【单选题】A remarkable variety of insects live in this planet. More species of insects exist than all other animal species together. Insects have survived on earth for more than 300 million years, and may posse...
A.
strong, hard but flexible shell covers their soft organs and is resistant to chemicals, water and physical impact. Their wings give them the option of flying away from erous situations or toward food or mates. Also, insects have an enormous reproductive capacity: An African ant queen can lay as many as 43,000 eggs a day.Another reason for their success is the strategy of protective color. An insect may be right before our eyes, but nearly invisible because it is cleverly disguised like a green leaf, lump of brown soil, gray lichen (青苔), a seed or some other natural object. Some insects use bright, bold colors to send warning signals that they taste bad, sting or are poison. Others have wing patterns that look like the eyes of a huge predator, confusing their enemies. Some insects also imitate bitter-tasting insects; hungry enemies are fooled into avoiding them.
相关题目：
【单选题】原始群体性状差异较大的异花授粉园林植物，实生选种时一般采用()。
A.
一次单株选择
B.
一次混合选择
C.
混合-单株选择
D.
单株-混合选择
【单选题】在没有授粉的番茄柱头上，涂抹一定浓度的生长素溶液，所得到的无籽果实，其染色体数是
A.
体细胞的一半
B.
受精卵的一半
C.
与体细胞相同
D.
与卵细胞相同
【判断题】花期较高的湿度有利于枣花授粉受精、坐果。()
A.
正确
B.
错误
【多选题】壁蜂授粉常用的巢管有
A.
芦苇管
B.
塑料管
C.
玻璃管
D.
纸管
【多选题】果树授粉的方法有
A.
人工辅助授粉
B.
蜜蜂授粉
C.
壁蜂授粉
D.
大风授粉
【单选题】风媒花：风：授粉（）
A.
蔬菜：温室：育苗
B.
果树：雨水：增产
C.
小麦：雪：丰收
D.
绿色植物：阳光：光合作用
【判断题】枣树座果率低的主要原因是授粉受精不良。
A.
正确
B.
错误
【单选题】向日葵和番茄都能产生果实和种子，向日葵的果实就是平时我们吃的“瓜子”。在上述两种植物开花期间，遇到了连续的阴雨天，影响了植物的授粉。管理人员及时喷洒了一定浓度的生长素。下列叙述正确的是 [ ]
A.
两种植物都能形成无子果实，产量均未受影响
B.
番茄形成无子果实，产量未受影响；向日葵形成无子果实，产量下降
C.
两种植物都能形成无子果实，产量下降
D.
番茄形成有子果实，产量上升；向日葵不能形成无子果实
【单选题】向日葵和番茄都能产生果实和种子，向日葵的果实就是平时我们吃的“瓜子”。在上述两种植物开花期间，遇到了连续的阴雨天，影响了植物的授粉。管理人员及时喷洒了一定浓度的生长素。下列叙述正确的是 [ ]
A.
两种植物都能形成无子果实，产量均未受影响
B.
番茄形成无子果实，产量未受影响；向日葵形成无子果实，产量下降
C.
两种植物都能形成无子果实，产量下降
D.
番茄形成有子果实，产量上升；向日葵不能形成无子果实
【单选题】A remarkable variety of insects live in this planet. More species of insects exist than all other animal species together. Insects have survived on earth for more than 300 million years, and may posse...
A.
strong, hard but flexible shell covers their soft organs and is resistant to chemicals, water and physical impact. Their wings give them the option of flying away from erous situations or toward food or mates. Also, insects have an enormous reproductive capacity: An African ant queen can lay as many as 43,000 eggs a day.Another reason for their success is the strategy of protective color. An insect may be right before our eyes, but nearly invisible because it is cleverly disguised like a green leaf, lump of brown soil, gray lichen (青苔), a seed or some other natural object. Some insects use bright, bold colors to send warning signals that they taste bad, sting or are poison. Others have wing patterns that look like the eyes of a huge predator, confusing their enemies. Some insects also imitate bitter-tasting insects; hungry enemies are fooled into avoiding them.
【单选题】A remarkable variety of insects live in this planet. More species of insects exist than all other animal species together. Insects have survived on earth for more than 300 million years, and may posse...
A.
strong, hard but flexible shell covers their soft organs and is resistant to chemicals, water and physical impact. Their wings give them the option of flying away from erous situations or toward food or mates. Also, insects have an enormous reproductive capacity: An African ant queen can lay as many as 43,000 eggs a day.Another reason for their success is the strategy of protective color. An insect may be right before our eyes, but nearly invisible because it is cleverly disguised like a green leaf, lump of brown soil, gray lichen (青苔), a seed or some other natural object. Some insects use bright, bold colors to send warning signals that they taste bad, sting or are poison. Others have wing patterns that look like the eyes of a huge predator, confusing their enemies. Some insects also imitate bitter-tasting insects; hungry enemies are fooled into avoiding them.