请讲解生物综合题---**Question 33**
**Question Stem:**
33. (5分) 第七次全国人口普查结果显示, 截至2020年11月1日零时, 我国31个省、自治区、直辖市和现役军人的总人口 (不包括香港、澳门特别行政区和台湾地区) 性别比 (每100个女性, 对应的男性数量) 为105.07。为什么人群中男女性别比例接近1:1呢? 请结合下图进行分析:
**Diagram Description:**
* Type: Genetics diagram illustrating sex determination in humans.
* Main Elements:
* Figures labeled "男" (Man) and "女" (Woman) at the top.
* Arrows from "男" point to two nodes representing male gametes: one labeled "X" and another labeled "(1)".
* An arrow from "女" points to a node representing the female gamete, labeled "X".
* Arrows connect male and female gametes to form zygotes ("受精卵").
* Male gamete "X" and female gamete "X" combine, with arrows pointing to node "(2)". Node "(2)" is labeled "XX". An arrow points from "(2)" to a "受精卵" labeled "XX".
* Male gamete "(1)" and female gamete "X" combine, with arrows pointing to node "(3)". Node "(3)" is labeled "X". An arrow points from "(3)" to a "受精卵" (not explicitly labeled with chromosome composition, but implied to be XY based on subsequent text).
* An arrow points from the "受精卵 XX" to node "(4)", and then to the label "女性的性染 (色体组成为)".
* An arrow points from the second "受精卵" (formed via node (3)) to the label "男性的性染色体组成为 [1]".
* Based on the accompanying text, node (1) represents the Y chromosome, node (2) represents the XX combination (leading to female), and the outcome of male (1) [Y] + female X is an XY zygote (leading to male). The label "X" on node (3) appears to be a diagram error; it should likely represent the XY combination.
**Relevant Text/Fill-in-the-blanks:**
* (1) 人类的性别是由性染色体的组成决定的。男性的性染色体组成为 [1] , 女性的性染色体组成为 XX。
* (Answer for [1] is XY based on context).
* (2) 图中④的性别是_______。
* (Answer is Female based on diagram).
* (3) 男性产生_______种类型的精子, 其数目相等; 女性产生_______种类型的卵细胞。
* (Answer for types of sperm is 2; answer for types of egg cells is 1 based on human genetics).
* 生殖过程中, 不同类型的精子与卵细胞结合形成受精卵的比例一般为1:1。因此, 人群中男性和女性的比例一般为1:1。
**Question 34**
**Question Stem (Partial):**
34. (5分) 2021年9月, 第十四届全运会将在我省隆重举行。为响应“全民全运”的号召, 本学
(4) 一对夫妇准备生一个孩子, 这个孩子是女孩的可能是为____。
的比例一般为1:1。
**Relevant Text/Fill-in-the-blanks:**
* (4) 一对夫妇准备生一个孩子, 这个孩子是女孩的可能是为____。
* (Likely asks for the probability, which is 1/2 or 50%).
* 的比例一般为1:1。 (Appears to be trailing text, possibly related to the previous question or context for this one, reinforcing the 1:1 sex ratio).
**Question 35 (Partial)**
**Question Stem (Partial):**
35. (5分)
**Question 36 (Partial)**
**Question Stem (Partial):**
36. (4分)