O 2 are gmos hazardous to the environment chapter 41

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o 2. Are GMOs hazardous to the environment? Chapter 41: Puberty: LH & FSH - Brain maturation at puberty causes the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) o LH & FSH stimulate: Testes to produce the male sex hormone testosterone Ovaries to produce the female sex hormone estrogen Testosterone & estrogen = steroid hormones (lipids Follicle, corpus luteum, ovary, uterine tube, uterus, endometrium, cervix Estrogen, progesterone, CG, & the menstrual cycle - Ovaries to produce the female sex hormone estrogen - Upon fertilization, the corpus luteum continues to release estrogen & progesterone - Also releases a new hormone “CG,” which is excreted in the urine - Urine strip pregnancy tests work by detecting CG (pregnant) or no CG (not pregnant) - If the egg is NOT fertilized, the corpus luteum disintegrates, estrogen & progesterone levels fall, & the thickened endometrium disintegrates - The uterus then contracts (sometimes causing menstrual cramps) & squeezes out the excess endometrial tissue - Causes the flow of tissue & blood called menstruation Sperm structure: acrosome, nucleus, mitochondria, flagellum
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- - o Atop the nucleus lies a specialized lysosome called an acrosome : Contains enzymes to dissolve protective layers around the egg, enabling the sperm to enter & fertilize it o Behind the head is the midpiece, which is packed with mitochondria Mitochondria provide the energy needed to move the tail (long flagellum) o Whiplike movements of the tail propel the sperm through the female reproductive tract o Relatively constant testosterone ensures constant new sperm growth throughout the male lifespan Scrotum, testes, epididymis, vas deferens, urethra - Testes à epididymis à vas deferens à urethra - Epididymis & vas deferens = tubes that store & conduct sperm - Urethra conducts urine out of the body during urination & sperm out of the body during ejaculation - Around a hundred million sperm produced each day are stored in the vas deferens and epididymis - 3 glands important for semen & contribution of each - Semen = the fluid ejaculated from the penis - About 5% sperm, mixed with secretions from 3 types of glands: - The seminal vesicles = fluid is high in sugar (energy), basic pH to counter the acidic vagina
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- The prostate gland = fluid with a basic pH & a consistency allowing sperm to move more freely - The bulbourethral glands = fluids to neutralize traces of acidic urine that may be left in the urethra Contraception: vasectomy, tubal ligation, hormone treatment, barrier methods, IUDs, spermicide, rhythm method, morning-after pill - Several effective techniques have been developed for contraception —the prevention of pregnancy o More permanent forms include vasectomies & tubal ligations, which disrupt the pathways in which sperm or eggs must travel o More temporary forms include hormone treatment, RISUG/VasalGel, & barrier methods o Less reliable forms include spermicide, the rhythm method, & withdrawal - Vasectomy : an operation in which the vas deferens leading from each testis can be severed & tied, clamped, or sealed o Sperm are still produced
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