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

Question

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

BlackTom AI · Accepted Answer

Let's examine each statement in light of sex determination in the tammar wallaby and general mammalian biology.
Option 1: 'SRY expression determines scrotal development' — This aligns with the idea that SRY expression drives testes development, which in turn influences downstream androgen production and male-associated traits. If SRY is expressed, gonads develop as testes, which then produce testosterone and related hormones that influence male differentiation, including scrotal development. Although the direct causal chain to scrotal development can be more complex and involve multiple downstream hormones, this statement captures the key role of SRY in initiating male (testicular) development that ultimately leads to male external genitalia features. Therefore, this option is consistent with known mechanisms and is considered true in the provided context.
Option 2: 'Penis development is regulated by the number of X chromosomes' — This is incorrect. In mammals, penis development is not determined by chromosome count alone; sex differentiation is directed by the presence of the SRY gene on the Y chromosome, which initiates testis formation and subsequent androgen-mediated development. X-number does not deterministically control penile development.
Option 3: 'Dihydrotestosterone can only be made via the classical steroid pathway' — This is inaccurate. DHT can be produced through alternative routes as well, such as conversion from testosterone by 5α-reductase, which is part of the typical pathway but not exclusive to a single “classical” route. The wording here oversimplifies androgen biosynthesis and overstates exclusivity of a single pathway.
Option 4: 'Androgen synthesis requires DHEA and androstendione' — This is misleading. While DHEA and androstenedione are precursors in androgen synthesis, they are not strictly required in all contexts; androgen synthesis can proceed via multiple precursor pools and enzymatic steps depending on species, tissue, and developmental stage. The statement overgeneralizes the precursor requirement.
Option 5: 'Testosterone levels are similar in male and female pouch young' — This is false. In most marsupials, as in other mammals, males develop higher expected testosterone levels due to testicular production, influencing male-specific development. Therefore, they are not typically similar between sexes in pouch young.

BIOL30001_2025_SM2 Exam: Reproductive Physiology (BIOL30001_2025_SM2)- Requires Respondus LockDown Browser

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

查看解析

登录即可查看完整答案

类似问题

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

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

Question at position 18 Sex determination is the developmental basis for what gametes an adult organism will be able to produce. Which of the following mechanisms of sex determination did we discuss in class?ChromosomalEnvironmentalGenetic

Question at position 6 Sex determination is the developmental basis for what gametes an adult organism will be able to produce. Which of the following mechanisms of sex determination did we discuss in class?GeneticEnvironmentalChromosomal

Chromosomal differences between males and females are determined in humans at conception.

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

Evaluate the following statement: "Haplodiploidy is a sex determination system that is common to all insect species in the order Hymenoptera."

Question at position 9 Individuals with an XO karyotype are in humans and in fruit flies.male, malemale, femalefemale, malefemale, femalemale, hermaphroditic

更多留学生实用工具

考试浏览器助手

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