Name: ___________________________ Date: ____________ BIOLOGY 12 REPRODUCTIVE SYSTEM PRACTICE 1) For each of the number parts, give the name and function. 1) prostate gland: provides alkaline fluid to seminal fluid/semen for acidic (urethra/vagina) 2) urethra: carries urine/semen through penis 3) penis: sexual reproduction and excretion of urine 4) testis: male gonads to produce sperm and testosterone (male sex hormone) 5) vas deferens: carries sperm from epididymis to urethra during ejaculation 6) seminal vesicle: provides fructose to seminal fluid for 7 energy for sperm 7) bulbourethral (Cowper’s) glands: provides lubricant to seminal fluid to help sperm swim 2) For each of the number parts, give the name and function. 1) oviduct: transports eggs from ovaries to uterus; site of fertilization 2) ovary: female gonads that produce eggs, estrogen and progesterone (female sex hormones) 3) uterus: where fetus develops 4) cervix: opening of uterus to vagina 5) vagina: receives penis during intercourse and serves as birth canal 3) Which of the following labeled structures is the Cowper’s gland? A. W B. X C. Y D. Z Testosterone is produced in the A. epididymis B. prostate gland C. interstitial cells D. seminiferous tubules Which of the following is not a function of seminal fluid? A. provides a suitable pH B. supplies an energy source C. causes the uterus to contract D. constricts the urethra during ejaculation 4) The structure labeled X is the A. uterus B. cervix C. follicle D. oviduct Which of the following, if present in urine samples, would indicate pregnancy? A. estrogen B. progesterone C. luteinizing hormone (LH) D. human chorionic gonadotropin (HCG) 5) When testosterone levels in a man’s bloodstream decrease A. the hypothalamus shuts down B. more progesterone is secreted C. luteinizing hormone (LH) secretion is increased D. follicle-stimulating hormone (FSH) secretion is blocked 6) a) Label the following diagram in the blanks provided. b) Most birth-control pills work by preventing egg maturation. These pills contain which of the following hormones? oviduct ovary uterus A. estrogen B. testosterone C. luteinizing hormone (LH) D. follicle-stimulating hormone(FSH) vagina 7) a) Give two functions of each of the following hormones. Estrogen: -secondary sexual characteristics (breast development) -high levels during Ovarian Cycle cause FSH to decrease and increase GnRH to create an LH surge for ovulation -cause endometrium to thicken, become glandular and vascular during Uterine Cycle LH (luteinizing hormone): -promotes development of corpus luteum to produce progesterone -surge in production causes ovulation b) Describe two hormonal changes that occur in the mother as a result of implantation. -human chorionic gonadotropin (HCG) is produced which stops the corpus luteum from disintegrating right away and stop producing progesterone -placenta produces progesterone and estrogen which stop the anterior pituitary from releasing FSH and LH as well as maintain the lining of the uterus 8) Identify the labelled structures in the diagram above and give one function of each. W = acrosome: has enzymes to penetrate egg X = head: holds nucleus of sperm Y = middle piece: mitochondria for tail Z = tail: movement of sperm 9) Which letter indicates the seminal vesicle? A. W B. X C. Y D. Z Label the other parts on the diagrams, and give one function for each. W = prostate: provides alkaline fluid to seminal fluid/semen for acidic (urethra/vagina) X = vas deferens: carries sperm from epididymis to urethra during ejaculation Y = seminal vesicle: provides fructose to seminal fluid for energy for sperm Z = epidiymis: for sperm maturation 10) The duct that is used by both the reproductive and excretory systems in males is the A. ureter B. urethra. C. renal pelvis. D. vas deferens. 11) Which structure would contain the greatest concentration of mitochondria? A. W B. X C. Y D. Z 12) State the effects that each of the following hormones has on the body during puberty. Testosterone: (three effects) -development of secondary sexual characteristics: body hair growth on face, genitals and armpits, enlargement of the larynx, muscle and skeletal growth, release of oils and sweat (potentially causing acne and body odour) and baldness (depending on genetics) Estrogen: (three effects) -development of secondary sexual characteristics: body hair on genitals and armpits, fat distribution, and widening of hips Follicle stimulating hormone: (two effects) -promotes the stimulation of sperm in testes of males -promotes the stimulation of egg/ovum in ovaries of females 13) a) Give two functions for each of the following structures. Testes: -produce sperm -produce testosterone Ovaries: -produce ova -produce estrogen and progesterone b) Name the hormone that is involved in a positive feedback loop and explain one of its functions. -Estrogen: high levels of estrogen cause the hypothalamus to release more GnRH which causes the anterior pituitary to release more LH – this LH surge causes ovulation 14) a) Days 1-3: low levels of sex hormones cause endometrium to disintegrate and blood vessels to rupture; on day 1 a flow of blood and tissues (menses) passes out of the vagina b) Days 7-14: increased production of estrogen by new ovarian follicle causes the endometrium to thicken and to become vascular and glandular c) Days 15-27: increased production of progesterone by corpus luteum causes the endometrium to double in thickness –if pregnancy does not occur the corpus luteum degenerates and the low level of sex hormones causes the uterine lining to break down again 15) Which of the following describes the hormonal levels on day one of a 28-day uterine cycle? C 16) a) Complete this summary table of the ovarian cycle. GnRH, FSH estrogen GnRH, LH progesterone b) i) What is the event that occurs on Day 14? OVULATION ii) What causes this event to occur? -high levels of estrogen cause hypothalamus to increase GnRH which causes a surge in LH production on Day 13 c) What causes Phase 2 to end? -progesterone levels reach their highest there is negative feedback to the anterior pituitary gland causing less LH secretions -less LH secretions causes the degeneration of the corpus luteum which stops production of progesterone and estrogen -without high levels of progesterone, the endometrium cannot maintain its thickness and will start to disintegrate causing menses d) Describe the effects of implantation (pregnancy) on the ovarian cycle. -embryo implants in thick endometrium -placenta produces human chorionic gonadotropin (HCG) which prevents the corpus luteum from degenerating (as it would normally) until the placenta can produce its own progesterone and estrogen -progesterone and estrogen shut down the anterior pituitary gland so that no new follicles mature and maintain the lining so that the corpus luteum is no longer needed 17) a) blastula b) uterus c) neurala d) corpus luteum e) acrosome f) epididymis 18) List all the constituents of seminal fluid (including the gland that produced the constituent). Give two functions of seminal fluid. -fructose = seminal vesicle -alkaline fluid = prostate gland -lubricant = bulbourethral (Cowper’s) gland -provides medium for sperm to swim in -gives nutrients and acid protection for trip 19) a) What gland is the source of luteinizing hormone (LH)? -anterior pituitary gland b) What is the function of luteinizing hormone (LH) during the last half of the ovarian cycle (days 15 to 28)? -LH promotes the development of the corpus luteum which secretes progesterone -progesterone causes the uterine lining to buld up -as levels increase a negative feecback control to anterior pituitary gland stops producing LH so that the corpus luteum begins to disintegrate and menstruation occurs 20) a) seminiferous tubule b) acrosome c) epididymis d) ovary e) uterus f) prostate gland 21) a) luteinizing hormone b) estrogen c) vagina d) acrosome e) epididymis f) interstitial cells 22) List, in correct order, the structures through which human sperm pass as they travel from the testes until they leave the body. Name and indicate the location of any glands which contribute fluids to the process. -seminiferous tubules -epididymis -vas deferens -urethra -seminal vesicles: behind urinary bladder -prostate gland: underneath urinary bladder -bulbourethral/Cowper’s gland: under prostate gland 23) The female reproductive system is carefully regulated by hormones produced by the brain and some of the sex organs. Explain the effect the following would have on the reproductive system: a) A failure of the corpus luteum to degenerate 20 days after ovulation. -corpus luteum would keep producing progesterone and endometrium would continue to thicken and mucus glands would keep secreting – no follicle would develop into egg b) A lack of FSH production during the first 15 days of the menstrual cycle. -FSH stimulates the follicles which produce estrogen in the ovaries -lack of FSH would cause low levels of estrogen and perhaps no follicular development which would lead to egg development 24) Name the source and describe the function of FSH (follicle stimulating hormone) in the female reproductive system. Source: anterior pituitary gland Functions: stimulate the follicle in the ovary which produces estrogen 25) Describe the effects of estrogen in the female body -development of secondary sexual characteristics -causes endometrium to thicken and become vascular and glandular 26) Describe the hormone changes in a female that occur as a result of implantation of the embryo. -progesterone and estrogen levels remain high (first because of corpus luteum not degenerating (human chorionic gonadotropin (HCG) produced by placenta prevents degeneration) and because placenta makes them -progesterone and estrogen shut down the anterior pituitary gland so that no new follicles mature and maintain lining of uterus for embryo 27) Fill in the blanks in the table below. STRUCTURE urethra epididymus Seminiferous tubules Penis FUNCTION Passageway for urine and semen (in males) Passageway for urine (in females) Site of sperm maturation sperm production male organ of copulation 28) State what happens to the numbered items with the correct lettered term. Write the letter of that term in the space at the right. A. acrosome 1. sperm mature here 1. B B. epididymous 2. location of spermatogenisis 2. D C. mid-piece 3. contains enzymes needed for fertilization 3. A D. seminiferous tubules 4. contains energy producing mitochondria 4. C 29) a) What is seminal fluid? -seminal fluid is made up of secretions from the prostate gland, seminiferous tubules and bulbourethral (Cowper’s) gland and added to sperm -seminal fluid provides nutrients, energy and acid protection to the sperm b) List two glands that contribute to the formation of seminal fluid? -prostate gland -seminiferous tubules -bulbourethral (Cowper’s) gland 30) Name the source of progesterone and describe its role in the uterine cycle. -progesterone is made in the corpus luteum -its role is to secrete progesterone to cause the endometrium to thicken and mucus glands to mature and secrete mucus to prepare uterus for embryo implantation 31) a) What structure secretes luteinizing hormone (LH)? -anterior pituitary gland b) What is the function of the luteinizing hormone during the menstrual cycle? -surge of LH levels on Day 13 cause ovulation during Day 14 -decrease in levels causes the corpus luteum to degenerate (which decreases progesterone and estrogen levels 32) a) Name the process which results in the production of “D” in the diagram -ovulation b) What is the function of “C” in the diagram -corpus luteum secretes progesterone which causes the endometrium to thicken and become vascularized and produce more mucus through secretory glands in preparation for pregnancy 33) Describe the role of a positive feedback loop in childbirth. -oxytocin is made in the hypothalamus and stored in posterior pituitary gland -oxytocin is released by the posterior pituitary gland when sensory nerves in the cervix (due to baby’s head exerting pressure on the cervix) send a nerve signal to the posterior pituitary gland to release oxytocin -oxytocin is released into the blood and causes stronger contractions of the uterus which causes greater stimulation of the sensory nerves which causes more oxytocin to be released which causes stronger uterine contractions and so on -this loop is stoped when the baby is pushed out of the uterus stopping the stimulation of sensory nerves to the pituitary gland. 34) The birth control pill contains estrogen and progesterone. Explain how the birth control pill prevents pregnancy. -the birth control pill contains estrogen and progesterone -these hormones shut down the production of FSH and LH so that no follicle begins to develop in the ovaries; since ovulation does not occur, pregnancy can not take place 35) Describe how testosterone and sperm levels are controlled by feedback loops. -GnRH from the hypothalamus stimulates the anterior posterior pituitary gland to secrete FSH and ICSH -FSH stimulates the testes to produce sperm –inhibin is made as well -ICSH (LH) stimulates the testes to produce testosterone -testosterone and inhibin levels are detected by the hypothalamus and the anterior pituitary gland –if levels are high then the hypothalamus will reduce GnRH which will reduce FSH and ICSH (LH) -this is a negative feedback loop 36) Relate the roles of GnRH, FSH, LH, estrogen, and progesterone to the uterine and ovarian cycles. -the hypothalamus controls GnRH -GnRH stimulates the anterior pituitary gland to produce FSH and LH Ovarian Cycle -FSH stimulates the follicle to produce estrogen -LH stimulates the corpus luteum to produce progesterone -progesterone causes the endometrium to build up and high levels cause the anterior pituitary to stop releasing LH which leads to degeneration of the corpus luteum Uterine Cycle: -low levels of hormones cause disintegration of endometrium and rupture of blood vessels = menses -increased production by follicles cause the endometrium to thicken, become vascular and glandular -increased production of progesterone causes the endometrium to double in thickness and secrete a thick mucus -if hormone level lowers then the uterus breaks down