Chapter 27: The Reproductive System

This set of flashcards covers key concepts, facts, and processes related to the reproductive system, including reproductive anatomy, hormone regulation, gametogenesis, and cycles of reproduction.

What is the main purpose of the reproductive system?

To produce offspring by forming gametes, bringing them together, combining genetic information through fertilization, and supporting fetal development.

At what stage does the reproductive system become functional?

At puberty.

What are gametes in males and females?

Sperm in males and ova (eggs) in females.

What is formed when sperm and egg fuse?

A zygote.

What are primary sex organs in males and females?

Testes in males and ovaries in females.

What do gonads produce besides sex cells?

Sex hormones.

What are the sex hormones for males?

Androgens.

What are the sex hormones for females?

Estrogens and progesterone.

What roles do sex hormones play in the body?

They influence the development and function of reproductive organs, sexual behavior, and growth of other organs.

Where are sperm produced in males?

In the seminiferous tubules of the testes.

What is the purpose of the scrotum?

To keep the testes cooler than core body temperature for optimal sperm production.

What two muscles control the temperature of the testes?

Dartos and cremaster muscles.

What is the path sperm takes during ejaculation?

Epididymis, ductus deferens, ejaculatory duct, and urethra.

What are the accessory sex glands in males?

Seminal vesicles, prostate gland, and bulbourethral glands.

What is the role of the seminal vesicles?

They secrete a fluid that contributes to semen volume.

What does the prostate gland secrete?

A milky fluid that makes up about one-third of semen volume.

What do bulbourethral glands produce?

Thick, clear mucus that neutralizes acidic urine.

What is semen composed of?

Sperm and secretions from accessory glands.

What role do prostaglandins in semen play?

They decrease cervical mucus viscosity and stimulate uterine contractions.

What occurs during ejaculation?

The propulsion of semen from the male duct system.

What is the process of sperm production called?

Spermatogenesis.

What type of cell division produces sperm?

Meiosis.

What is the result of meiosis in terms of chromosome number?

The number of chromosomes is halved from diploid (2n) to haploid (n).

What is a spermatogonium?

A stem cell that eventually develops into sperm through mitosis and meiosis.

What occurs during spermiogenesis?

Spermatids develop into mature sperm.

What are the three main parts of a sperm cell?

Head, midpiece, and tail.

What hormonal axis regulates male reproductive function?

Brain-Testicular (HPG) Axis.

What does GnRH stimulate in the anterior pituitary?

The release of FSH and LH.

What effect does FSH have in males?

It stimulates sustentacular cells to release androgen-binding protein (ABP).

What is the function of testosterone in the male body?

It stimulates spermatogenesis and development of male secondary sex characteristics.

What changes occur in males during puberty?

Enlargement of testes and scrotum, growth of facial hair, and voice deepening.

What is the first sign of puberty in females?

Budding breasts.

What is menarche?

The first menstrual period.

What happens to estrogen production during menopause?

It declines significantly.

What physical change occurs to reproductive organs during menopause?

Reproductive organs and breasts atrophy.

What is the ovarian cycle?

A monthly series of events associated with the maturation of an egg.

What are the phases of the ovarian cycle?

Follicular phase, ovulation, and luteal phase.

What triggers ovulation?

A surge in LH levels.

What does the corpus luteum secrete?

Progesterone and estrogen.

What is the uterine cycle?

Cyclical changes in the uterine endometrium in response to ovarian hormones.

During which phase does the endometrium shed?

Menstrual phase.

What is the role of cervical mucus during the menstrual cycle?

To block sperm entry except during ovulation.

What occurs during the proliferative phase of the uterine cycle?

The endometrium rebuilds itself.

What happens during the secretory phase of the uterine cycle?

The endometrium prepares for potential implantation of an embryo.

How is hormonal regulation of oogenesis achieved?

Through the hypothalamus, pituitary gland, and ovaries.

What role do estrogens play in the female reproductive system?

They promote oogenesis and the growth of reproductive tract structures.

What happens to the primary oocyte during meiosis?

It arrests in prophase I until triggered to continue.

What is the difference between primary, secondary, and vesicular follicles?

Primary follicles contain primary oocytes; secondary follicles are maturing; vesicular follicles are ready for ovulation.

What is Mittelschmerz?

A twinge of pain sometimes felt during ovulation.

What is the corpus albicans?

A scar left after the degeneration of the corpus luteum if pregnancy does not occur.

How does aging affect oocyte numbers in women?

Oocyte numbers decline sharply, leading to menopause.

What is the main driver of the LH surge before ovulation?

Rising estrogen levels.

What does a lack of sufficient estrogen during menopause result in?

Atrophy of reproductive organs and associated symptoms.

What is the relationship between FSH and LH levels during the menstrual cycle?

They have a feedback relationship where rising levels of one affect the release of the other.

What are the key differences between mitosis and meiosis?

Mitosis produces two identical cells; meiosis produces four non-identical haploid cells.

What physiological changes occur in the body due to testosterone during puberty in males?

Increased muscle mass, bone density, and maturation of reproductive organs.

What hormonal changes occur in the female body as they approach menopause?

Declining estrogen and irregular ovulation cycles.

What specific secretions does the prostate gland contribute to semen?

A slightly acidic fluid containing citrate and enzymes.

What anatomical structure contains the testis and regulates temperature?

The scrotum.

How many chromosomes do human gametes have?

23 chromosomes, making them haploid.

What influences the growth of ovarian follicles?

Follicle stimulating hormone (FSH) levels.

How is sperm delivered to the female reproductive tract?

Through the penis during ejaculation.

How does the female reproductive system change at puberty?

Breast development, body fat distribution, and menstrual cycle onset.

What is the primary function of the uterine tubes?

To receive the ovulated oocyte and provide a site for fertilization.

What determines the timing of ovulation in the ovarian cycle?

The surge of luteinizing hormone (LH).

What constitutes the external female reproductive organs?

The vulva, including the labia, clitoris, and external vaginal opening.