R EPRODUCTION 6.6 ;] IB OUTLINE Allott pgs. 56-58 BREA ALOTAYA BIANCA ARGUILLA NATASHA GUENTHER.

REPRODUCTION 6.6 ;]

IB OUTLINE

Allott pgs. 56-58

BREA ALOTAYA

BIANCA ARGUILLA

NATASHA GUENTHER

IB STANDARDS- SECTION 6.6

6.6.1 : DRAW AND LABEL THE ADULT FEMALE REPRO. SYSTEMS

Female Anatomy: The main parts required for IB includes the ovary, the oviduct, cervix, uterus, bladder, urethra, vulva, large intestine, and vagina Ovary: Oviduct: Cervix: Uterus: Bladder: Urethra: Vulva: Large Intestine: Vagina:

FIGURE 46.9 REPRODUCTIVE ANATOMY OF THE HUMAN FEMALE

FIGURE 46.9 REPRODUCTIVE ANATOMY OF THE HUMAN FEMALE (CONTINUED)

6.6.1 : DRAW AND LABEL THE ADULT MALE REPRO. SYSTEMS Male Anatomy: The main parts required for IB includes

the bladder, sperm duct, erectile tissue, penis, urethra, foreskin, testies, seminal vesicle, prostate gland, epididymis, scrotum, and testies Bladder: Sperm Duct: Erectile tissue: Penis: Urethra: Foreskin: Testies: Seminal Vesicle: Prostrate Gland: Epididymis: Scrotum: Testies:

6.6.2: OUTLINE THE ROLE OF HORMONES IN THE MENSTRUAL CYCLE, INCLUDING FSH, LH, ESTROGEN, AND PROGESTERONE

Menstrual Cycle: Controlled by hormones FSH and LH, produced in the anterior pituitary glands, and Estrogen and progesterone, produced in the Ovaries; consists of three distinct stages: menstruation, follicular phase, and luteal phase Menstruation: also called menstrual bleeding or period;

the flow normally serves as a sign that a woman has not become pregnant.

Follicular phase: this phase is also called the proliferative phase because a hormone causes the lining of the uterus to grow, or proliferate, during this time

Ovulation is switch btwn Follicular and luteal; occurs when egg has matured

Luteal phase: also called the secretory phase; an important role is played by the corpus luteum, the solid body formed in an ovary after the egg has been released from the ovary into the fallopian tube.


FSH ( follicle stimulating hormone) : a hormone synthesized and secreted by gonadotropes in the anterior pituitary gland. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the human body. In females, FSH stimulates growth and recruitment

of immature Ovarian follicles in the ovary. As the follicles mature, one becomes dominant. It then releases chemicals that decrease the FSH production by inhibiting GnRH production in the hypothalamus.

In males, FSH enhances the production of androgen-binding protein by the Sertoli cells of the testies and is critical for spermatogenesis.


LH (Luteinizing Hormone) : also known as Lutropin; LH is a hormone produced by the anterior pituitary gland. In females, a rise of LH triggers ovulation In males, LH sti,ulates Leydig cell production of

testosterone. Works together with FSH


Estrogen: responsible for growth and development of female sexual characteristics and reproduction in humans and animals. Associated with estrone, estradiol, and estriol

Estrone & estradiol: ovaries Estriol: by placenta during pregnancy

Produced in the ovaries, adrenal glands, and fat tissues

Circulates in the bloodstream and binds to estrogen receptors on cells in targeted tissues

Controls growth of the uterine lining during the first part of the menstrual cycle, responsible for breast changes & other metabolic processes ( bone growth and cholesterol levels)


Progesterone: a hormone in our body that stimulates and regulates various functions Plays a role in maintaining pregnancy and sexual

desires Produced in the ovaries, the placenta (during

pregnancy), and the adrenal glands Prepares body for conception, pregnancy, and

regulate menstrual cycle Responsible for stimulating growth of the uterine

lining (endometrium), causing it to thicken during preovulatory phase of the cycle

Works together with estrogen


Female sex hormones recap: LH and FSH – pituitary gland

These affect the processes in the ovary FSH stimulates the development of follicles, fluid filled

sacs that hold egg LH stimulates follicles to become mature and release

the egg, ovulation, developing into the corpus luteum Estrogen and Progesterone- ovaries

Both stimulate the development of female secondary sexual characteristics during puberty and stimulate the development of uterus lining that is needed during pregnancy

Unless pregnancy occurs, hormone levels rise and fall with cycle [see chart]

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FIGURE 46.15 THE REPRODUCTIVE CYCLE OF THE HUMAN FEMALE

6.6.3: ANNOTATE A GRAPH SHOWING HORMONE LEVELS IN THE MENSTRUAL CYCLE, ILLUSTRATING THE LEVELS BETWEEN CHANGES IN HORMONE LEVELS, OVULATION, MENSTRUATION, AND THE THICKENING OF THE ENDOMETRIUM

The menstrual cycle occurs in women who are not pregnant. It is controlled by FSH, LH, estrogen, and progesterone. During the cycle, hormone levels change in response to the bodily changes. 1. FSH level rises and stimulates follicle growth and

estrogen secretion by the cells of the follicle 2. Estrogen makes the follicle cells produce more FSH

receptors and therefore respond more efficiently to the FSH

3. Positive feedback between estrogen and FSH cause the estrogen levels to rise and stimulate the repair of the uterus lining

4. Estrogen levels rise to a peak and stimulate LH secretion by the pituitary gland

5. LH rises to a peak and causes the egg to be released from the follicle-ovulation


Changes in hormone levels (cont.) : 6. LH causes the follicle cells to secrete less

estrogen (negative feedback) and more progesterone. After ovulation occurs, LH causes the follicle to develop into the corpus luteum

7. The corpus luteum secretes large amounts of progesterone, causing the uterus lining the prepare for an embryo

8. High levels of progesterone and estrogen inhibit FSH and LH secretion, causing negative feedback

9. Progesterone and estrogen levels fall if no embryo has been formed and allows for FSH and LH secretion again

10. FSH levels rise again, repeating the cycle.

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6.6.4: LIST THREE ROLES OF TESTOSTERONE IN MALES Testosterone: is a steroid hormone from the androgen

group. In mammals, testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid.

In men, testosterone plays a key role in health and well-being as well as in osteoporosis . On average, an adult human male body produces about forty to sixty times more testosterone than an adult female body, but females are, from a behavioral perspective (rather than from an anatomical or biological perspective), more sensitive to the hormone. However the overall ranges for male and female are very wide, such that the ranges actually overlap at the low end and high end respectively.

6.6.4: LIST THREE ROLES OF TESTOSTERONE IN MALES

Testosterone: The male sex hormone Three roles:

The developing testes of a male fetus secrete testosterone, which causes the male genitalia, including the penis, to develop in the fetus

During puberty, levels of testosterone rise and cause male secondary sexual characteristics to develop- ex..: pubic hair, an enlarged penis, and growth of skeletal muscles

In adulthood, testosterone maintains the sex drive, which is the instinct to encourage sexual intercourse, therefore passing on their genes to their offspring

Is a hormone needed to stimulate sperm production by the testes.

INFERTILITY: NOT ON IB SYLLABUS, BUT MENTION IN ALLOTT BOOK TO INTORDUCE IN VITRO FERTILIZATION

Infertility: when couples are unable to achieve fertilization and pregnancy despite sexual intercourse during ovulation period. Can be temporary or permanent Approx. 1 in 6 couples have temporary or

permanent infertility In vitro fertilization (IVF) has been a possible

solution to infertility IVF can overcome blocked oviducts that prevent

conception However, IVF cannot compensate for low or zero sperm

count in males

6.6.5 OUTLINE THE PROCESS OF IN VITRO FERTILIZATION (IVF) In vitro fertilization- is the process of fertilization by

manually combining an egg and sperm in a laboratory dish. When the IVF procedure is successful, the process is combined with a procedure known as embryo transfer, which is used to physically place the embryo in the uterus.

IVF consists of 10 steps over a nine week timetable: 1. weeks 1-3: a drug is injected once a day for three weeks, to

stop the woman’s normal period cycle 2. weeks 4-beg. Of 5: Large doses of FSH are injected once a day

or 10-12 days to stimulate the ovaries to develop many follicles 3. week 5: HCG (another hormone..obviously not important to

IB) is injected 36 hours before egg collection, to loosen the egg in the follicles and to make them mature

4. week 5- the man provides semen by ejaculating into a jar. The sperm are processed to concentrate the healthiest ones

5. week 5- the eggs are extracted from the follicles using a device inserted through the wall of the vagina

6.6.5 OUTLINE THE PROCESS OF IN VITRO FERTILIZATION (IVF)

IVF timetable continued: 6. week 5: each egg is mixed with sperm in a

shallow dish and kept overnight in an incubator 7. week 6: dishes are checked to see if

fertilization has occurred 8. week 6: two-three embryos are selected and

placed into the uterus, via a long plastic tube 9. b/w week 7&8: a pregnancy test is done to

determine if embryos have been implanted 10. end of week 9: a scan is done to see if

pregnancy is continuing normally; heart should be visibly beating

6.6.6: DISCUSS THE ETHICAL ISSUES ASSOCIATED WITH IVF

CLASS DISCUSSION FOR CLASS PARTICIPATION POINTS!!!!!!!!!! ;]

6.6.6: DISCUSS THE ETHICAL ISSUES ASSOCIATED WITH IVF

Inherited forms of infertility might be passed on to children, which means that the suffering of the parents is repeated

More embryos are often produced than are needed and the spare embryos are sometimes killed, denying them the chance at life

Embryologists select embryos to transfer to the uterus, so humans are deciding whether new individuals survive or die

IVF is an unnatural process, carried out in labs, in contrast to natural conception occurring as a result of an act of love

Infertility should be accepted as the will of God and it is wrong to try to circumvent it by using IVF to have a child

Many forms of infertility are due to environmental factors, so offspring will not inherit them

Any embryos that are killed during IVF are unable to feel pain or suffer, because their nervous system has not developed

Suffering due to genetic disease could be reduced if embryos were screened before being transferred to the uterus

Parents willing to go through the process must have strong desires for kids and so are likely to become loving parents

Infertility brings great unhappiness to parents who want to have children, which in some cases can be ov4rcome by IVF

Against IVF For IVF

R EPRODUCTION 6.6 ;] IB OUTLINE Allott pgs. 56-58 BREA ALOTAYA BIANCA ARGUILLA NATASHA GUENTHER.

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Transcript of R EPRODUCTION 6.6 ;] IB OUTLINE Allott pgs. 56-58 BREA ALOTAYA BIANCA ARGUILLA NATASHA GUENTHER.