Final exam

Estrogens secreted from the developing follicles in the ovary stimulate the regeneration of the stratum functionalis. This cell proliferation repairs and rebuilds the endometrium.

Describe how the endometrium responds to rising blood estrogen levels during the proliferative phase of the uterine cycle.

the secondary oocyte arrests in metaphase II until fertilization occurs.

Meiosis

Preovulatory, ovulatory and post ovulatory.

Name the three phases of the ovarian cycle.

If fertilized, implantation of an embryo is now possible and the new embryo will be nutritionally maintained by the endometrium.

Once again, what is the function of the fully developed endometrium?

The sharp decline in ovarian hormones triggers the release of GnRH, LH and FSH from the hypothalamus and anterior pituitary and the cycle begins again.

As blood hormone levels all reach a low point, how does the hypothalamus respond?

The corpus luteum is developed after the follicle ruptures. The ruptured follicle, called the corpus hemorrhagicum, will develop into the corpus luteum under the influence of LH.

Describe corpus luteum formation.

If the secondary oocyte is not fertilized it degenerates. The corpus luteum also degenerates and the cycle begins again with new follicular development triggered by GnRH and FSH. If fertilization occurs, the secondary oocyte completes meiosis giving rise to an ovum which will undergo a successive series of cell divisions and eventually implant in the uterus. The corpus luteum will be supported by hormones from the placenta and will not degenerate until the end of pregnancy.

Contrast ovarian events if fertilization occurs with when it does not.

Declining progesterone levels lead to the reduction of blood supply to the endometrium. This results in the degeneration and shedding of the stratum functionalis of the endometrium.

Conventionally, the beginning of the menstrual phase is marked by the monthly menstrual flow. How does the endometrium respond to declining progesterone levels?

Certain neurosecretory cells in the hypothalamus secrete gonadotropin releasing hormone, GnRH. This releasing hormone is then carried by the blood to the anterior pituitary where it binds to receptors on gondotrophic cells.

Describe gonadotropin releasing hormone (GnRH) production.

The release of LH is inhibited, which suppresses the ovulation of another secondary oocyte.

Why isn't another follicle stimulated at this stage?

White blood cells get out of blood vessels

Define diapedesis.

The making of RBC's

Define erythropoiesis

Blood Cell Production

Define hematopoiesis

Stopage of bleeding

Define hemostasis

lymphatic Capillaries located within the Gastrointestinal tract

Define lacteals

interstitial fluid transported withing lymph vessels

Define lymph

Amount of blood returning to the heart

Define venous return

GnRH then stimulates the gondotrophic cells of the anterior pituitary to increase the secretion of Leutinizing hormone and Follicle stimulating hormone.

Describe GnRH affects on the male anterior pituitary.

Following ovulation the uterus reaches maximum preparedness for implantation. Under the influence of rising ovarian hormone levels the endometrium continues to thicken and the endometrial glands secrete glycogen. The endometrium is now ready to receive an embryo if fertilization occurs.

Describe how the endometrium responds to rising progesterone and estrogen during the secretory phase of the uterine cycle.

Sertoli cells in the testes release a protein hormone called inhibin when the level of spermatogenesis needed for the male reproductive system has been attained. Inhibin acts as a negative feedback control on the anterior pituitary to regulate FSH secretion.

Describe inhibin secretion. From where? Why? Effect?

The LH surge causes a rapid growth in the mature or Graafian follicle. The primary oocyte continues its meiotic process and arrests at metaphase II as a secondary ooctye. The graafian follicle subsequently ruptures, releasing the secondary oocyte into the pelvic cavity.

Describe mature, or graafian, follicle development.

Prior to ovulation and under the influence of FSH, many primordial follicles develop into primary follicles.The primary follicles continue to develop into secondary follicles. The follicular cells surrounding the primary oocyte divide and secrete estrogen. Usually one of the secondary follicles becomes dominant and develops into a mature Graafian follicle.

Describe primary follicle development.

These are the postovulatory and secretory phases. The collapsed follicle becomes the corpus luteum secreting large amounts of progesterone, estrogen and inhibin. These promote endometrial proliferation and secretion. High levels of inhibin stop the production of LH and FSH by the anterior pituitary. If the secondary oocyte is not fertilized the corpus luteum degenerates and the cycle begins again.

Describe secretory and anatomical events during days fifteen to twenty-eight of the female reproductive cycle.

Estrogen levels peak causing an LH surge. The LH stimulates the mature follicle to rupture and release the secondary oocyte.

Describe secretory and anatomical events of day fourteen of the female reproductive cycle.

The corpus luteum secretes both estrogen and progesterone, increasing both of their blood levels.

Describe the glandular function of the corpus luteum.

The corpus luteum, simulated by LH, secretes progesterone and estrogen which supports uterine endometrial changes in preparation for implantation of an embryo in the event that fertilization occurs.

Describe the glandular function of the corpus luteum.

The secretion of estrogens from the follicular cells in the ovary reaches causes blood estrogen levels to rise. In addition, secretion of LH and FSH from the anterior pituitary also reach peak levels.

Describe the glandular function of the primary follicle.

This is the menstrual phase. Progesterone and estrogen levels are at a low level. Menses occurs. GnRH pulses more frequently promoting FSH and LH levels to rise. Primary follicles are stimulated to develop.

Describe the secretory and anatomical events during days one to five of the female reproductive cycle.

This is the preovulatory and proliferative phases. The production of estrogen increases stimulating further follicular development. The endometrial cells proliferate, increasing the thickness of the endometrium. Rising estrogen levels stimulate increased pulsing of GnRH and increased secretion of FSH and LH. The primary oocyte undergoes meiosis to form the secondary oocyte.

Describe the secretory and anatomical events during days six to thirteen of the female reproductive cycle.

The mature Graafian follicle ruptures as a consequence to the LH surge

Describe what happens to the Graafian follicle as a result of the LH surge.

Systole is contraction, diastole is relaxation

Distinguish between systole & diastole

Inhibin is delivered to the anterior pituitary gondotrophic cells and acts on the gonadotrophs to reduce FSH secretion, thus decreasing the rate of spermatogenesis.

Explain the negative feedback loop that regulates spermatogenesis at homeostatic levels.

FSH travels in the bloodstream from the anterior pituitary to the ovaries. At the ovaries FSH promotes follicular growth. The increased follicular growth promotes estrogen production.

FSH is produced by the anterior pituitary. Describe its affects on the ovaries.

Multipotent Stem Cells

From what stem cell do all formed elements arise from?

At the beginning of the month the levels of GnRH slowly rise. The GnRH binds to receptors in the anterior pituitary and stimulates the release of the gonadotropins, follicle-stimulating hormones (FSH) and luteinizing hormone (LH).

Gonadotropin releasing hormone (GnRH) is produced by the hypothalamus. Describe its affects.

LH surges, Estrogens and FSH decrease

Hormone levels

The regulation begins in the hypothalamus with the release of gonadotropin releasing hormone.

Hormones regulate this cycle. Where does this regulation begin?

The increase in ovarian hormones inhibits the release of LH and FSH. The release of inhibin from the corpus luteum enhances this inhibitory effect.

How do increasing estrogen and progesterone levels, as well as inhibin, affect the anterior pituitary?

Testosterone and DHT both bind to the same intranuclear receptors. Together, these androgens regulate male prenatal development and the development of male sexual characteristics. These include enlargement of the male sex organs, secondary sex characteristics that begin at puberty and protein synthesis.

How do testosterone and DHT affect male prenatal development?

loses tissue

How does the thymus change as we age?

4

How many oxygen molecules can be bound to one RBC?

cervical, axillary, inguinal lymph nodes

Identify the three major lymph node clusters in the body

The three phases are the menstrual phase, proliferative phase and the secretory phase.

Identify the three phases of the uterine cycle.

Ovarian and uterine or menstrual cycles.

Identify the two female reproductive cycles.

Testosterone stimulates the final stages of spermatogenesis. It is also converted to dihydrotestosterone (DHT). DHT may function to promote sperm cell formation.

If you haven't summarized it already, what affect does testosterone have on spermatogenesis?

pressure in pleural cavity and pressure in alveoli

Intrapleural vs. intrapulmonary

As the levels of FSH and LH decline, the corpus luteum begins to degenerate. This degeneration reduces the production of estrogen and progesterone.

What affect do declining LH and FSH levels have on the corpus luteum?

The small increases in estrogen levels inhibit the release of FSH and LH into the blood, but promote their accumulation in the anterior pituitary.

What affect does increasing estrogen have on FSH and LH release from the anterior pituitary?

Luteinizing hormone binds to the receptors of the Interstitial Cells of Leydig between the seminiferous tubules, and stimulates the secretion of testosterone.

What affect does luteinizing hormone (LH) have on the testes?

Progesterone increases the growth and development of the uterus and prepares it for possible implantation.

What affect does progesterone have on the uterus?

Under the influence of FSH and testosterone, the Sertoli cells produce Androgen-binding protein (ABP).

What affect does testosterone and FSH have on the testes?

Androgen - binding protein binds to testosterone and helps maintain high testosterone levels near the spermatogenic cells.

What affect is the affect of androgen-binding protein?

nervous and endocrine systems

What are the two main extrinsic influences on heart activity?

Alpha(a) and Beta(B) chains

What are the two major components of hemoglobin?

The high estrogen level creates a positive feedback on both the hypothalamus and the pituitary.

What effect does HIGH estrogen levels have on the anterior pituitary?

The LH surge initiates ovulation and triggers a decline of estrogen produced by the follicle. LH also transforms the ruptured follicle into the corpus luteum.

What effect does a rush of LH and FSH have on the ovary?

The Graafian follicle collapses and develops into the corpus luteum.

What happens to the Graafian follicle following ovulation?

Erythropoietin

What hormone stimulates erythropoiesis?

Respiratory Membrane because it includes the blood vessels

What is the actual site of gas exchange?

Exchange of substances between blood and tissues

What is the basic function of capillaries?

prevent backflow of blood

What is the basic function of heart valves?

reduce surface tension in alveoli

What is the function of surfactant in the alveoli?

To sustain growth and development of the implanted embryo.

What is the function of the uterine endometrium?

rapid attachment

What is the large protein found in erythrocytes function?

Hemoglobin

What is the large protein found in erythrocytes?

If not fertilized the corpus luteum degenerates and the levels of progesterone and estrogen drop. The stratum functionalis of the uterine wall sloughs off and menstruation begins.

What occurs if the secondary oocyte is not fertilized? These activities mark the beginning of the menstrual phase, which is the beginning of a new cycle.

The hypothalamus, anterior pituitary and the testes.

What organs are involved in hormonal control of male reproductive functions?

The anterior pituitary, ovaries, hypothalamus and the uterus.

What organs are involved in regulation of the female reproductive cycle?

The uterine cycle is under the control of the ovarian hormones.

What regulates the uterine cycle?

Occurs in the red bone marrow which is in Spongy Bone

Where does hematopoeisis occur in the body?

Veins contain valves

Which blood vessels contain valves?

left

Which ventricle can achieve a greater pressure?

to prevent the backflow of blood.

Why are they necessary in veins to have valves?

keeps you healthy

Why is diapedesis necessary?

it must achieve a greater force to push blood further

Why is the left ventricle thicker than the right ventricle?