Exam 4- JONES

What are gonads?

• primary reproductive organs

• testes and ovaries

• produce gametes

A gamete + gamete = zygote describes what process?

sexual reproduction

XX is a _____________ and XY is a _________________.

female, male

Do males or females have the SRY gene present?

MALES

The SRY gene produces a protein called _____________ and that tells the primordial gonad we want testes.

TDF

The fetal testes develop into 2 main types of cells. What are their names? What hormones do they secrete?

1. Sertoli cells- MIS

2. Leydig cells- Testosterone

In addition to MIS, Sertoli cell’s main function is:

support cells, help with SPERM PRODUCTION (spermatogenesis)

(Think: Sertoli= Sperm)

What is the function of MIS, testosterone, and DHT in sexual differentiation?

MIS- tells mullerian ducts to regress (die)

Testosterone- tell Wolffian duct to develop, convert to DHT

DHT- development (external organs ex: penis)

In men ________________ ducts develop. In woman _________________ ducts develop.

Wolffian ducts, Mullerian ducts

Females have no ___________ gene so the primordial gonad differentiate into fetal ______________.

SRY, ovaries

The absence of what two hormones cause the Mullerian ducts to transform, wolffian ducts regress, and female genitalia to develop?

absence of TESTOSTERONE AND MIS

Chromosomal disorders may occur due to nondisjunction. How does a person with XO chromosomes present?

• “Turner’s Syndrome”

• absent gonads (infertile), female external

• short, webbed neck

How does a person with XXX chromosomes present?

• not a big deal

• no major dysfunction

How does a person with YO chromosomes present?

• lethal 😵

How does a person with XXY chromosomes present?

• “Klinefelter’s”

• high T levels

• poorly developed male sex organs- infertile

• tall

• low IQ

Where is sperm made? Where does it mature?

made- testis

matures- epididymis

When you orgasm, sperm travels through the ______________________ and receives fluids from _______________________ to make semen.

When you orgasm, sperm travels through the vas deferens and receives fluids from seminal vesicles to make semen.

What is the functional unit of the testes?

seminiferous tubule

Leydig cells are stimulated by ____ and Sertoli cells are stimulated by _____.

Leydig cells are stimulated by LH and Sertoli cells are stimulated by FSH.

(Leydig= LH , Sertoli= FSH)

What is spermatogenesis?

creation of sperm

When will spermatogenesis occur in a male?

puberty

The head of sperm contains an enzyme called acrosome in order to do what?

penetrate egg

Is the pH of sperm basic or acidic?

basic

What is the function of the scrotum? (aka what type of blood flow does it have)

COUNTER-CURRENT BLOOD FLOW

What IS counter-current blood flow?

warm blood flows down testes and transfers head to blood coming OUT of testes

Explain why counter-current blood flow is important?

SPERM NEEDS LOWER TEMPERATURES (aka why balls are not inside the

What is cryptorchidism?

lack of decent of testes (balls don’t drop)

What are some functions of testosterone?

• fetal development

• anabolic (RBCs, muscle mass, bones)

• sperm production

Testosterone is made from what and is transported in the blood using what?

• made from cholesterol

• transported using sex steroid binding globulin

How is TESTOSTERONE converted to DHT? (aka what enzyme)

5-a-reductase

Sertoli Cells produce what hormone that inhibits FSH?

inhibin

What part of reproduction is sympathetic stimulation? Which is parasympathetic?

a. erection

b. ejaculation

Para- erection

Symp- Ejaculation (everything else)

What is the problem with BPH? What’s enlarged?

too much DHT, enlarged prostate (DHT stimulates prostate growth)

BPH is treated with ______________________________.

5a-reductase inhibitors

What is the inability to maintain an erection to allow for vaginal insertion? tx?

Erectile Dysfunction

• tx: PDE5 inhibitors