皮皮学，免费搜题
登录
搜题
【简答题】
下列是生物生殖过程中染色体变化示意图，据图回答： (1)请画出图中精子、卵细胞、受精卵细胞中染色体和基因。 (2)若图为人类生殖过程中染色体变化的示意图，图中所示的是一对性染色体，父方体细胞中性染色体组成为XY，则产生的精子有两种，分别为含_________和含_________性染色体，体细胞中的性染色体组成为_________，产生的卵细胞中只含_________性染色体。 (3)精子和卵细胞融合的过程叫_____________。 (4)从生殖细胞结合形成受精卵的角度看，决定生男生女的关键是由_________（生殖细胞）所决定，从理论上讲，男女比例大致是_____________。
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
【简答题】对于施工周转材料，能计入材料定额消耗量的是（ ）。
【单选题】What are the main features of Vault III?
A.
It is the oldest building resembling a galley.
B.
It is likely the headquarters of the troops of Vault I and Vault II.
C.
It is the largest one among the three vaults.
D.
It has a 1. 95-meter-high robust marshal as the commander.
【简答题】San Francisco's Chinatown is the biggest and oldest in the country. It's the third most visited tourist destination in the city. It's also the city's most densely populated neighbor- hood. So why are....
【简答题】Carl: Hi. My name's Carl. Nice to meet you. Pancho: Nice to meet you, too. My name is Francisco. Carl: What? Pancho: Francisco, but all my friends and family back in Peru call me Pancho. Carl: Okay, P...
【单选题】听力原文： Man: My secretary tells me that you'd like to know something about mechanical engineering. What I can do is give you some idea of the variety of specialties within the field. Woman: I'd apprecia...
A.
She is planning to buy a refrigerator.
B.
She is interested in fashion design.
C.
She wanted to know something about a subject.
D.
She asked the man to help her find a job.
【单选题】I think this is the oldest coin ______ I have ever seen. [ ]
A.
which
B.
who
C.
what
D.
that
【简答题】单幼儿园人身伤害事故
相关题目：