A and P week 7 reproduction and fetus

Why are the testes located in the scrotum outside the body?

Sperm production requires a temperature 2–4°C below core body temperature.

What muscles regulate testicular temperature?

Dartos and cremaster muscles.

What tissue divides the scrotum into two compartments?

The scrotal septum.

Where does spermatogenesis occur?

: In the seminiferous tubules of the testes.

What is the function of Sertoli (sustentacular) cells

Support sperm development, form the blood-testis barrier, and regulate germ cell survival.

ame the stages of sperm development.

Spermatogonia → Primary spermatocytes → Secondary spermatocytes → Spermatids → Spermatozoa.

How long does spermatogenesis take?

Approximately 64 days.

What process reduces the chromosome number in sperm cells?

Meiosis.

What is spermiogenesis?

The final stage of spermatogenesis where spermatids mature into spermatozoa.

What are the three parts of a sperm cell?

Head (with nucleus and acrosome), midpiece (with mitochondria), and tail (flagellum).

: What is the function of the acrosome?

Contains enzymes that help the sperm penetrate the egg.

Trace the path of sperm from formation to ejaculation.

Seminiferous tubules → Epididymis → Ductus deferens → Ejaculatory duct → Urethra.

What is the epididymis and its role?

A coiled tube where sperm mature and are stored.

What do seminal vesicles secrete?

Alkaline fluid with fructose (nourishes sperm), ~60% of semen volume.

What does the prostate gland contribute?

Milky alkaline fluid that enhances sperm motility and coagulates semen.

Q: What do bulbourethral (Cowper's) glands do?

Secrete pre-ejaculate that lubricates and neutralizes urethra.

What tissues make up the penis?

Two corpora cavernosa and one corpus spongiosum.

What causes an erection?

Vasodilation triggered by nitric oxide (NO), increasing blood flow into erectile tissues.

What are the roles of LH and FSH in males?

LH stimulates Leydig cells to produce testosterone; FSH stimulates Sertoli cells for spermatogenesis.

What is benign prostatic hyperplasia (BPH)?

Non-cancerous enlargement of the prostate that can cause urinary issues.

What is the mechanism behind drugs like Viagra (sildenafil)?

Inhibits PDE5, allowing prolonged vasodilation and erection.

What are the primary functions of the female reproductive system?

Producing gametes, supporting fetal development, and delivering the baby.

What is the female gonad and what does it produce?

The ovary; it produces oocytes and hormones like estrogen and progesterone.

What is oogenesis?

The process of forming female gametes.

When is meiosis in oogenesis completed?

Only after sperm penetration at fertilization.

What is folliculogenesis?

The maturation of ovarian follicles, each containing an oocyte.

What triggers ovulation?

A surge in luteinizing hormone (LH).

What is the corpus luteum and its role?

Remnant of the follicle post-ovulation; secretes progesterone to prepare for pregnancy.

What phases make up the ovarian cycle?

Follicular phase, ovulation, luteal phase.

What are the three phases of the menstrual cycle?

Menses, proliferative, and secretory phases.

What causes menstruation to occur?

Drop in progesterone due to corpus luteum degradation.

Where does fertilization usually occur?

: In the ampulla of the uterine tube.

How is the oocyte moved to the uterus?

By cilia and smooth muscle contractions in the uterine tube.

What is the function of the uterus?

To nourish and support the developing fetus

Which layer of the endometrium is shed during menstruation?

The stratum functionalis.

What are the three main stages of prenatal development?

Pre-embryonic (weeks 1–2), embryonic (weeks 3–8), and fetal period (week 9–birth)

What is a zygote?

A diploid cell resulting from the fusion of a sperm and an oocyte​

What is a morula?

solid ball of cells resulting from cleavage, formed around day 3 after fertilization

What is a blastocyst?

A hollow ball of about 100 cells containing an inner cell mass, forming around day 5

When does implantation occur and how?

Around day 6–7; the blastocyst embeds in the endometrium using trophoblast enzymes​

Name the four embryonic membranes.

Amnion, yolk sac, allantois, and chorion​

What is embryonic folding?

The transformation of the flat embryonic disc into a 3D, tube-like structure​

What are the functions of the placenta?

Nutrition, respiration, excretion, endocrine support​

What structures connect the fetus to the placenta?

Umbilical arteries (2) and one umbilical vein, surrounded by Wharton's jelly

What are chorionic villi and their role?

Finger-like projections that facilitate exchange of nutrients and gases between mother and fetus​

When does sexual differentiation occur?

During weeks 9–12 of fetal development​

What duct systems are involved in sexual differentiation?

Müllerian ducts (female) and Wolffian ducts (male)​

How long is pregnancy

typical pregnancy, measured from the first day of the last menstrual period, lasts about 40 weeks (280 days). This is further divided into three trimesters, each approximately 13 weeks long. A full-term pregnancy is considered to be between 39 and 40

weeks.

What is the function of fetal circulatory shunts?

To bypass immature organs like the lungs and liver until birth​

What allows oxygen and nutrients to reach the fetus?

Placental exchange through the umbilical vein​

What happens during each phase of the menstrual cycle and the ovarian cycle And what hormones cause it 

Menstrual Cycle (Approx. 28 Days) 1. Menstrual Phase (Days 1–5)

• What happens: Shedding of the endometrial lining (period).

• Hormones:

  • Estrogen & Progesterone low.

  • Low hormone levels trigger menstruation.

2. Proliferative Phase (Days 6–14)

• What happens: Endometrium rebuilds and thickens.

• Hormones:

  • Estrogen rises (from developing follicles).

  • LH and FSH begin to rise nearing ovulation.

3. Secretory Phase (Days 15–28)

• What happens: Endometrium prepares for implantation.

• Hormones:

  • Progesterone peaks (from corpus luteum).

  • Estrogen remains moderately high.

  • If no fertilization, both drop, triggering menstruation.

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Ovarian Cycle (Approx. 28 Days) 1. Follicular Phase (Days 1–13)

• What happens: Follicles develop in ovaries.

• Hormones:

  • FSH stimulates follicle growth.

  • Estrogen rises as follicles mature.

2. Ovulation (Day 14)

• What happens: Mature egg is released.

• Hormones:

  • LH surge triggers ovulation.

  • FSH also spikes briefly.

3. Luteal Phase (Days 15–28)

• What happens: Corpus luteum forms from ruptured follicle.

• Hormones:

  • Progesterone rises (maintains endometrium).

  • If no pregnancy, corpus luteum degenerates, hormones drop.

What does the uterine lining do 

• Support for Pregnancy:

  If a fertilized egg implants, the endometrium provides nourishment and support for the developing embryo and fetus throughout pregnancy. 

• Intermediate Pharmacology: PDF of Medication Profile cards (PCP)

• Intermediate Pharmacology: PDF of Medication Profile cards (PCP)