Reproductive System

Seminal vesicle

_____ secretes a fluid that makes up most of the components of the semen.

hormone inhibin

The ________ stops the release of GnRH and FSH, which will cause spermatogenesis to slow down.

Testosterone

________ negatively feedback to the hypothalamus and pituitary to decrease the production of GnRH and LH.

negative feedback system

A(n) ________ occurs in the male with rising levels of testosterone acting on the hypothalamus and anterior pituitary to inhibit the release of GnRH, FSH, and LH.

male gonads

The ________ are the testes (singular: testis) hanging in the scrotum.

LH

________ also enters the testes and stimulates the interstitial cells of Leydig to make and release testosterone into the testes and the blood.

Corpus luteum

________ secretes estrogen and progesterone.

Estrogen

________ secreted at low levels during most of the cycle.

Immature follicles

________ have receptors for FSH but not LH.

seminal fluid

Semen, also known as ________, is much more than just sperm.

scrotum

The ________ contains two testes (testicles) where sperm are manufactured within tubes called seminiferous tubules, and the two epididymides where sperm are stored.

sperm begin

Inside each tubule, ________ as blob- like cells called spermatogonia lining the inner wall.

female egg maturation

Unlike ________, which occurs in cycles and ceases at menopause, sperm production is continuous, reducing gradually with age.

male

Unlike the ________, the female reproductive organs are located entirely inside the body.

Androgen

________ and Testosterone: affects primary and secondary sexual characteristics.

Mature follicle

________ have receptors for LH.

Corpus luteum

________ secretes estrogen and progesterone.

tail

Sperm develop in the testes and consist of a head, a midpiece, and a(n) ________.

Follicular tissue

________ develops into corpus luteum.

menstrual cycle

During each ________, follicle- stimulating hormone (FSH) causes one egg to begin development; this takes place inside a primary follicle.

presence of LH

Synthesize hormones and produce testosterone in the ________.

FSH

________ enters the testes and stimulates the Sertoli cells to begin facilitating spermatogenesis using negative feedback.

front section

The head contains the nucleus with densely coiled chromatin fibers (chromosomes), with a(n) ________- the acrosome that contains enzymes for penetrating the female egg.

human ejaculation

There are around 200 to 500 million sperm in an average in a single male ________.

new individual

Nurtures the development of and provides nourishment for the ________.

Egg fertilization

________ usually occurs in the ampulla, the eggs then travel through the isthmus to the uterus.

Sperm production

________ requires a slightly lower temperature than the human body that is why the scrotum hangs loosely outside the body cavity.

Stimulate spermatogenesis

________: sperm production in sertoli cells (lifetime process)

Granulosa cells of follicle

________ secretes estrogen.

vulva

The ________ and its structures form the external genitalia.

vagina

The ________ extends down from the cervix, the lower part of the uterus, to the vestibule, which is part of the vulva and the external genitalia.

uterine lining

The blastocyst attaches to the wall of the uterus and gradually implants itself into the ________.

female reproductive glands

The ________ (ovaries) are located within the abdomen.

internal genitalia

The ________ includes a three- part system of ducts: the uterine tubes, the uterus, and the vagina.

egg travels

The ripe ________ along the fallopian tube to the uterus, the muscular sac in which it develops into an embryo and then fetus.

egg cells

The ovaries produce ________ and release them for fertilization.

seminiferous tubules

Each testis is a mass of more than 800 tightly looped and folded vessels known as ________.

Bulbourethral gland

________ (Cowpers gland)- secretes a thick and clear mucus that lubricates and neutralizes any trace of acidic urine in the urethra.

Prostate gland

________- secretes a slightly alkaline milky fluid that is discharged as part of the semen.

Sperm

________ is only about 5 to 10 % of any given male single ejaculation and the rest is fructose (aka sugar), fatty acids, and proteins to nourish the ________ during their journey.

Rate of release

________ is increased (peaked) when approaching ovulation.

Sertoli cells

________: FSH stimulates spermatogenesis.

Follicle cells

________ produce the hormone inhibin which stops FSH production.

500 inch

A sperm is about 1 /________ long, but most of this is a tail.

LH

A surge of luteinizing hormone (________) causes the follicle to rupture and release the ripe egg- this is ovulation.

Estrogen

________ also stimulates thickening of endometrium.

LH

________ luteinizes remaining follicular tissue into corpus luteum.

corpus luteum

Luteinizes the follicle into the ________.

Corpus luteum

________ secretes female hormones.

the male gonads are the testes (singular

testis) hanging in the scrotum

the two oval-shaped testes (also called testicles) lie outside the body in a pouch of skin called the scrotum, where they can maintain the optimum temperature for sperm production

approximately 5° F, lower than body temperature

the head contains the nucleus with densely coiled chromatin fibers (chromosomes), with a front section

the acrosome that contains enzymes for penetrating the female egg

Seminal vesicle

secretes a fluid that makes up most of the components of the semen

Prostate gland

secretes a slightly alkaline milky fluid that is discharged as part of the semen

Bulbourethral gland (Cowpers gland)

secretes a thick and clear mucus that lubricates and neutralizes any trace of acidic urine in the urethra

the internal genitalia includes a three-part system of ducts

the uterine tubes, the uterus, and the vagina

no eggs are manufactured after birth

a female is born with a full set

THE VAGINA

A TUNNEL WITH THREE CORE FUNCTIONS

a surge of luteinizing hormone (LH) causes the follicle to rupture and release the ripe egg

this is ovulation

the lining of the empty follicle thickens into a corpus luteum

a temporary source of hormones

FERTILIZATION

A SPERM AND AN EGG FORM A ZYGOTE

THE ZYGOTE BECOMES AN EMBRYO

DEVELOPMENT PRIOR TO AND DURING IMPLANTATION

stimulate spermatogenesis

sperm production in sertoli cells (lifetime process)

Hypothalamus

Gonadotropin-releasing hormone (GnRH)

Anterior Pituitary

Gonadotropic hormones FSH and LH

Sertoli cells

FSH stimulates spermatogenesis

Leydig cells

LH stimulates hormone secretion

Androgen and Testosterone

affects primary and secondary sexual characteristics

Gonadotropins

Follicle-stimulating hormone (FSH)

Gonadotropins

Luteinizing hormone (LH)

Testes

Leydig cells

Androgens

Testosterone

OVARIAN CYCLE REGULATION

NEUROENDOCRINE PATHWAY

Gonadotropins

Follicle-stimulating hormone (LH)

Ovaries

Follicle & Corpus Luteum

ESTROGEN REGULATION

HIGH LEVELS

high estrogen

positive feedback on LH & FSH by stimulating GnRH