List two examples of secondary sex characteristics in

List two examples of secondary sex characteristics in females and two in males.
- Females: enlarged hips, weight gain.

- males: increased muscle mass, deeper voice.
Are there secondary sex characteristics that could be the basis of a reliable sex
determination test? Explain your answer.
- Yes, I do believe this could be the basis of reliable sex determination. I believe
this because in 1966 this was the method. And to me, it’s not as invasive. And
one can determine sex from external and internal reproductive anatomy.
- With that being said, it is hard to determine due to DSD’s (AMH)>
Regarding DSDs …
a. What does the abbreviation DSD stand for?
- DSD stands for differences in sex development.
b. How common are DSDs?
- DSD’s are not common… 1/100 may get this disease.
Answer the following questions using the table of DSDs.
1. CYP21A2 gene mutations
a. By what mechanism can a mutation in CYP21A2 change testosterone
levels?
- The mechanism is an enlarged adrenal gland, which can change
testosterone levels.
b. What changes in phenotype are typical in people with a CYP21A2
mutation?
- Enlarged clitoris, short vaginal cavity, elevated testosterone levels,
and decreased fertility.
2. SRY gene mutations
a. How can an error in chromosome segregation during meiosis affect
inheritance of the SRY gene?
- The error is when an X chromosome crossover between an X and
Y chromosome during meiosis.
b. What is the effect of a nonfunctional SRY gene on the development of
primary sex characteristics?
- Low testosterone and and small testicles.

c. Which sex is typically assigned at birth to an individual with a mutation that
results in a nonfunctional SRY gene?
- Male
3. XO
a. How can an error in chromosome segregation result in Turner syndrome?
- During meiosis an error in chromosome segregation can occur
resulting in one complete X chromosome, with the other X
chromosome being partially or completely missing.
b. Can an individual with Turner syndrome have biological children?
- An individual with Turner syndrome cannot have biological children
due to infertility and do not produce eggs.
1. AR gene mutation
a. Which phenotypes may arise in an individual with a mutation in the AR
gene?
- Phenotypes that may arise in an individual with a mutation in the
AR gene are female external reproductive anatomy. While males
have internal anatomy. And breasts may develop.
b. In humans, the AR gene is located on the X chromosome. If a person who
is XY has a complete deletion of the AR gene, do you think giving them
testosterone injections during puberty would cause an increase in
expression of male secondary sex characteristics compared to not
receiving injections? Explain your answer.
-
2. XXY
a. Which of the following terms describes the process of homologous
chromosomes failing to separate correctly during meiosis?