True or false. In animals, sex is sometimes, but not always, determined by allosomes.

Question

BlackTom AI · Accepted Answer

Allosomes (sex chromosomes) such as X and Y are one common mechanism that determines sex, so the statement is True.

1) Relevant knowledge points and concepts
- Allosomes (sex chromosomes) are chromosomes that differ between sexes (e.g., XX/XY in mammals, ZW/ZZ in birds).  
- Sex determination in animals is diverse: genetic sex determination (GSD) via sex chromosomes, haplodiploidy (bees/ants), environmental sex determination (ESD, e.g., temperature-dependent sex determination in many reptiles), and social or hormonal cues in some fishes and invertebrates.

2) Step-by-step reasoning
- Many animals (mammals, some insects, birds) use allosomes to determine sex: presence/absence or combination of particular sex chromosomes leads to male or female development.  
- However, numerous animal lineages do not rely on allosomes:  
  - Reptiles (some turtles, crocodilians) use incubation temperature to set sex (ESD).  
  - Hymenoptera (bees, ants, wasps) use haplodiploidy: fertilized diploid eggs become females, unfertilized haploid eggs become males—no sex chromosomes required.  
  - Some fishes and amphibians can change sex in response to social environment or hormones.  
- Because both types of mechanisms occur in animals, sex is “sometimes” determined by allosomes and “not always.”

3) Calculations
- None required for this conceptual question.

4) Why the correct answer is correct
- The presence of clear counterexamples (temperature-dependent sex determination, haplodiploidy, sex change) demonstrates that allosomes are not universally responsible for determining sex across animals. Therefore the qualifier “sometimes, but not always” is accurate.

5) Why the other option is incorrect
- Choosing False would imply that allosomes never or always determine sex; claiming that allosomes always determine sex is incorrect because many animals use non-allosomal mechanisms.

Conclusion: The correct answer is True, which matches the provided answer.

True or false. In animals, sex is sometimes, but not always, determined by allosomes.判断题

类似问题

The SRY is defined as

Question at position 29 The SRY gene influences sex determination by transforming:Mullerian ducts into testesWolffian ducts into testesWolffian ducts into ovariesMullerian ducts into ovariesClear my selection

The sry gene on the Y chromosome encodes for: Y 染色体上的 sry 基因编码：

A fruit fly with a diploid set of autosomes has one X chromosome but no Y chromosome. This fly would be

Question at position 8 The SRY gene causes one to becomeandrogynousmalefemaleundifferentiatedsterile

Which of the following is true when determining the sex of a White Tree Frog

In the tammar wallaby, which of the following is true about sex determination?

Michelle and Greg are having a baby and are hoping for a boy. What is responsible for determining the sex of the baby?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单