Normal and abnormal development of GT [Autosaved] (1)

What is the purpose of the sex chromosomes in embryonic development?

They control the differentiation of the fertilized embryo into a male or female fetus.

What is the genetic female karyotype?

XX.

What is the purpose of the sex chromosomes in embryonic development?

They control the differentiation of the fertilized embryo into a male or female fetus.

What is the genetic female karyotype?

XX.

What is the genetic male karyotype?

XY.

What gene directs the gonad to become a testis?

SRY gene.

What happens in the absence of a Y chromosome?

The bipotential gonad differentiates into an ovary.

What is gonadal sex dependent on?

The presence of testes in males and ovaries in females.

Which ducts are present in all fetuses?

Both Mullerian and Wolffian ducts.

What characterizes phenotypic sex?

It is determined by the appearance of external genitalia and secondary sexual characteristics.

What are Müllerian ducts in females?

They develop passively to form fallopian tubes, uterus, and upper vagina.

What hormone do Sertoli cells produce to suppress female internal genitalia development?

Müllerian-inhibiting substance (MIS) or anti-Müllerian hormone (AMH).

What is the maximum number of primordial follicles present at 20 weeks gestation?

Six to seven million.

What is gametogenesis?

The process where germ cells undergo meiotic division, reducing their chromosome number to haploid.

What do the Wolffian ducts develop into in males?

Epididymis, vas deferens, and seminal vesicles.

What occurs when testosterone is absent in males during development?

Regression of the Wolffian ducts.

What happens under the influence of dihydrotestosterone during external genitalia development?

Determines the development of male external genitalia such as the penis.

What do the genital tubercle and urogenital sinus develop into in females due to the absence of masculinization?

The clitoris and lower vagina/labia minora.

What is ambiguous genitalia?

A condition where an individual's biological sex cannot be clearly classified as male or female.

What are disorders of sex development (DSD)?

Congenital conditions where the development of chromosomal, gonadal, or anatomical sex is atypical.

Which condition is characterized by a chromosomal sex of a female with male external genitalia?

Female pseudohermaphroditism.

What causes male pseudohermaphroditism?

A chromosomal sex of a male with female external genitalia.

Which syndrome is associated with 45XO karyotype?

Turner syndrome.

What hormone deficiency is associated with congenital adrenal hyperplasia?

Deficiency of 21-hydroxylase resulting in excess androgens.

What is the primary clinical presentation of Turner syndrome?

Primary amenorrhea and delayed or absent pubertal development.

What is the significance of the SRY gene in sexual development?

It initiates testis development and male differentiation.

What does the term 'gonadal dysgenesis' refer to?

A condition where the gonads do not develop properly.

What condition refers to the presence of both ovarian and testicular tissues?

True hermaphroditism.

What might be a treatment approach for ambiguous genitalia?

Plastic surgery and hormonal therapy.

What is the genetic sex of a person with Klinefelter syndrome?

47,XXY.

What is the function of androgen receptors in sexual differentiation?

They mediate the effects of androgens during the development of male external genitalia.

What can excessive exposure to androgens during pregnancy cause in female fetuses?

Masculinization of external genitalia.

What is the most common disorder of sex development?

Congenital adrenal hyperplasia.

Which syndrome is characterized by a 46,XY karyotype with female external genitalia?

Androgen insensitivity syndrome.

What hormonal treatment is often required for individuals with Turner syndrome?

Hormone replacement therapy (HRT).

What do the abdominal gonads from the undescended testes present a risk for?

Malignancy.

What happens to the Müllerian ducts in the presence of testosterone?

They regress in males due to AMH.

What is a common finding at birth for children with congenital adrenal hyperplasia?

Ambiguous genitalia.

What role does estrogen play in treatment for Turner's syndrome?

It supports the development of secondary sexual characteristics.

What is a major complication of untreated Turner syndrome?

Osteoporosis.

What is the chromosomal pattern associated with mixed gonadal dysgenesis?

46XY/45X mosaic.

What can maternal exposure to androgens during pregnancy induce?

Masculinization of female external genitalia.

What is a characteristic phenotype of Turner syndrome?

Short stature with webbed neck.

What is one of the clinical presentations of androgen insensitivity syndrome?

Primary amenorrhea.

What is necessary for the ovary to develop properly?

Intact germ cells.

What condition describes a female with XY chromosomes and absence of functional androgen receptors?

Androgen insensitivity syndrome.

What surgical procedures might individuals with ambiguous genitalia undergo?

Gonadectomy and plastic surgery.

What hormonal dysfunction is noted in congenital adrenal hyperplasia?

Inadequate cortisol production leading to hyperplasia.

What type of surgery might be performed to correct genital appearance in individuals with ambiguous genitalia?

Plastic surgery.

What are sex chromosomes responsible for in development?

They determine the chromosomal sex of an individual.

What is the role of the SRY gene?

SRY gene triggers the formation of testes in a developing embryo.

What are the two primary types of sex chromosomes?

X and Y chromosomes.

What does the presence of an SRY gene prompt?

The development of male reproductive structures.

What happens to gonads in the absence of a Y chromosome?

They develop into ovaries.

What are the embryonic structures present in both sexes?

Müllerian and Wolffian ducts.

How does the Wolffian duct contribute to male reproductive anatomy?

It develops into the epididymis, vas deferens, and seminal vesicles.

What is the impact of androgens on the Wolffian duct?

Androgens are required for the Wolffian ducts to develop into male structures.

What is the process by which sperm are produced?

Spermatogenesis.

What controls the growth of primordial follicles in females?

Gonadotropins such as FSH (follicle-stimulating hormone).

What is the result of testosterone action on the Müllerian ducts in males?

Regression of the Müllerian ducts.

What are secondary sexual characteristics?

Features that appear at puberty, influenced by sex hormones.

What does congenital adrenal hyperplasia affect?

Hormonal production in adrenal glands leading to abnormal sexual development.

What is the defining feature of androgen insensitivity syndrome?

Genetic males have female external genitalia.

What does the term 'pseudohermaphroditism' imply?

An individual has both male and female characteristics but with a typical chromosomal sex.

What results from a chromosomal pattern associated with Turner syndrome?

A female phenotype with a 45,X karyotype.

What hormonal therapy might individuals with Turner syndrome require?

Hormone replacement therapy (HRT) for estrogen.

What does the term 'gonadal dysgenesis' refer to?

Improper development of the gonads.

What is a clinical presentation of Klinefelter syndrome?

Presence of male external genitalia with reduced testosterone levels.

How does the body respond to excess androgens in fetal development?

Potential masculinization of female external genitalia.

What is the chromosomal makeup of Klinefelter syndrome?

47, XXY.

What surgical options are available for individuals with ambiguous genitalia?

Gonadectomy and reconstructive surgery.

What can excessive exposure to estrogens in fetuses cause?

Alterations in sexual differentiation.

What is the primary function of the Müllerian-inhibiting substance?

To prevent the development of female reproductive structures in males.

What role does genetic testing play in disorders of sexual development?

It helps diagnose DSD by identifying chromosomal abnormalities.

What is the significance of the genital tubercle in development?

It differentiates into external genitalia based on hormonal influence.

What is a characteristic feature of 47,XXX karyotype?

Often associated with minimal physical effects, but potential for developmental delays.

What is the impact of testicular feminization syndrome (TFM)?

Males with TFM have female external phenotype due to androgen receptor insensitivity.

What do people with Turner syndrome typically lack?

Ovaries, resulting in infertility and short stature.

What is ambiguous genitalia indicative of?

Potentially a mismatch between genetic and phenotypic sex.

___ is the process by which the ovary develops from the bipotential gonad.

Ovarian differentiation.

The presence of ___ leads to the development of male internal reproductive structures.

Testosterone.

___ is a condition where individuals have a typical female karyotype but male external genitalia.

Androgen insensitivity syndrome.

The main role of ___ in males is to promote the development of male secondary sexual characteristics.

Testosterone.

In the absence of androgens, the Wolffian ducts ___ during development.

Regress.

___ is the name of the gene that initiates the formation of testes.

SRY.

The ___ are responsible for producing sperm in males after puberty.

Testes.

The primary functions of the ___ are to store and mature sperm.

Epididymis.

The Mullerian ducts develop into the ___, ___, and upper vagina in females.

Fallopian tubes, uterus.

Congenital adrenal hyperplasia leads to an excess of ___ production.

Androgens.

A chromosomal pattern of 46,XX with male external genitalia indicates ___.

Female pseudohermaphroditism.

___ can cause the XY karyotype to exhibit female characteristics due to androgen receptor insensitivity.

Androgen insensitivity syndrome.

Testosterone acts on the ___ to stimulate the development of male external genitalia.

Genital tubercle.

The ___ is the primary hormone produced by the ovaries.

Estrogen.

___ are needed to initiate the menstrual cycle in females.

Gonadotropins.

Individuals with Turner syndrome often present with short stature and ___ neck.

Webbed.

In females, the primary site of gametogenesis is the ___.

Ovary.

___ occurs when there is a discrepancy between an individual's chromosomal and phenotypic sex.

Disorder of sex development (DSD).

In males, the presence of the ___ hormone leads to regression of the Müllerian ducts.

Müllerian-inhibiting substance (MIS).

In Turner syndrome, the karyotype is typically ___.

45,X.

The clinical presentation of ___ syndrome typically includes infertility and primary amenorrhea.

Turner.

In typical male development, the genital tubercle develops into the ___.

Penis.

___ is the medical term for ambiguous genitalia at birth.

Intersex condition.