Reproductive System Grade 9 PDF - Biology

Human Reproductive System Biology – Grade 9 GROUND RULES FOR PUBERTY CLASSES GROUND RULES FOR PUBERTY CLASSES SMPK PENABUR JAKARTA BIOLOGY ONLINE CLASS LEARNING OBJECTIVE HUMAN REPRODUCTIVE SYSTEM...

Human Reproductive System Biology – Grade 9 GROUND RULES FOR PUBERTY CLASSES GROUND RULES FOR PUBERTY CLASSES SMPK PENABUR JAKARTA BIOLOGY ONLINE CLASS LEARNING OBJECTIVE HUMAN REPRODUCTIVE SYSTEM QUIZ  LEARNING OBJECTIVE 1. To know the reproductive organs and understand its functions 2. To understand the reproductive processes that happens in human body (menstruation, fertilization, pregnancy) 3. To understand how to taking care reproductive organs and how to prevent sexual transmitted disease LEARNING OBJECTIVE 1. To know the reproductive organs and understand its functions Human reproductive system Male Organ and Function Female Organ and Function The Male Reproductive System Male Reproductive System The Female Reproductive System Female Reproductive Organs Brain Games  A sac like-pouch to holds 1 A sperm storage area that links the testes with the vas deferens 5 Birth canal 9 testes and regulate temperature for sperm production 2 Tube used to transports Channel for ejaculation sperm and semen to the urethra and penis 6 of sperm during copulation 10 Site of fertilization Responsible for the Surrounds the urethra 3 Responsible for the 11 under the bladder and 7 production of ovum and production of sperm and secretes a fluid that assists hormones (estrogen and testosterone. Located in with movement of the progesterone) the scrotum sac sperm 4 Site of embryo development 8 Catch the ovum after ovulation LEARNING OBJECTIVE 2. To understand the reproductive processes that happens in human body (menstruation, fertilization, pregnancy) Comparison Male Hormones Sperm Structure  Male Reproductive System (review) Hormones Control Sperm Formation Leydig cells: in tissue between the seminiferous tubules Produce testosterone: Governs growth, form, and functions of the male reproductive tract Stimulates sexual behavior Promotes secondary sexual traits: facial hair and deepening of the voice Seminiferous Tubules Are Coiled Inside the Lobes of the Testes Figure 46.12a Epididymis Seminiferous tubule Testis Primordial germ cell in embryo Cross section of seminiferous tubule Mitotic divisions Spermatogonial 2n stem cell Mitotic divisions Sertoli cell nucleus Spermatogonium 2n Mitotic divisions Primary spermatocyte 2n Meiosis I Secondary spermatocyte n n Meiosis II Lumen of seminiferous tubule Spermatids Early Neck spermatid n n n n (two stages) Tail Midpiece Head Differentiation Plasma (Sertoli cells membrane provide nutrients) Sperm cell n n n n Acrosome Nucleus Mitochondria  Sperm Form in Seminiferous Tubules Sperm (spermatozoa): male gametes Mature sperm: 9–10 weeks of processing Nourished with secretions from Sertoli cells Tail (flagellum) Midpiece; contains mitochondria Head Nucleus with DNA organized into chromosomes Acrosome: cap with enzymes to penetrate egg Figure 46.12ac Neck Tail Midpiece Head Plasma membrane Acrosome Nucleus Mitochondria Menstrual Cycle Female Hormones Fertilization, Conception, Embryo development Female Reproductive Organs (review) Ovaries Are a Female’s Primary Reproductive Organs Ovaries Release sex hormones Secondary sexual traits: fat deposits in breasts, hips, and buttocks Produce eggs during reproductive years Oocytes (immature eggs) Released into oviduct (site of fertilization) Travel to uterus  Ovaries Are a Female’s Primary Reproductive Organs Uterus Organ where baby grows and develops Myometrium (thick layer of smooth muscle) and endometrium (lining) Cervix: lower portion of the uterus Vagina Leads from the cervix to the outside  Menstrual Cycle Menstrual cycle: ~28 days A woman’s menstrual cycle is divided into four phases: menstrual phase follicular phase ovulation phase luteal phase The length of each phase can differ from woman to woman, and it can change over time.  Menstrual Phase The menstrual phase is the first stage of the menstrual cycle. It’s also when you get your period. This phase starts when an egg from the previous cycle isn’t fertilized. Because pregnancy hasn’t taken place, levels of the hormones estrogen and progesterone drop. The thickened lining of your uterus, which would support a pregnancy, is no longer needed, so it sheds through your vagina. During your period, you release a combination of blood, mucus, and tissue from your uterus. On average, women are in the menstrual phase of their cycle for 3 to 7 days. Some women have longer periods than others.  Menstrual Phase You may have period symptoms like these: cramps bloating mood swings irritability headaches tiredness low back pain  Follicular Phase The follicular phase starts on the first day of your period (so there is some overlap with the menstrual phase) and ends when you ovulate. It starts when the hypothalamus sends a signal to your pituitary gland to release follicle-stimulating hormone (FSH). This hormone stimulates your ovaries to produce around 5 to 20 small sacs called follicles. Each follicle contains an immature egg. Only the healthiest egg will eventually mature. (On rare occasions, a woman may have two eggs mature.) The rest of the follicles will be reabsorbed into your body. The maturing follicle sets off a surge in estrogen that thickens the lining of your uterus. This creates a nutrient-rich environment for an embryo to grow. The average follicular phaseTrusted Source lasts for about 16 days. It can range from 11 to 27 days, depending on your cycle. Oocytes Develop by Way of Cyclic Changes in the Ovary  Ovulation Phase Rising estrogen levels during the follicular phase trigger your pituitary gland to release luteinizing hormone (LH). This is what starts the process of ovulation. Ovulation is when your ovary releases a mature egg. The egg travels down the fallopian tube toward the uterus to be fertilized by sperm. The ovulation phase is the only time during your menstrual cycle when you can get pregnant. You can tell that you’re ovulating by symptoms like these: a slight rise in basal body temperature thicker discharge that has the texture of egg whites Ovulation happens at around day 14 if you have a 28-day cycle — right in the middle of your menstrual cycle. It lasts about 24 hours. After a day, the egg will die or dissolve if it isn’t fertilized.  Hormones Guide Ovulation Ovarian cycle Born with ~300 oocytes arrested in meiosis I One primary oocyte matures/month during the female’s menstrual cycle Primary oocyte Surrounded by a layer of nourishing cells Forms the follicle; grows due to FSH and LH Levels of estrogen increase Oocyte completes meiosis I before ovulation  Hormones Guide Ovulation Secondary oocyte Gets most of the cytoplasm; begins undergoing meiosis II Surge of LH Ovulation: release of secondary oocyte from the ovary Enters the oviduct Fimbriae help sweep it in If fertilization occurs, meiosis II is completed  Luteal Phase After the follicle releases its egg, it changes into the corpus luteum. This structure releases hormones, mainly progesterone and some estrogen. The rise in hormones keeps your uterine lining thick and ready for a fertilized egg to implant. During this phase, if you don’t get pregnant, you may experience symptoms of premenstrual syndrome (PMS). These include: bloating mood changes headache weight gain changes in sexual desire food cravings trouble sleeping The luteal phase lasts for 11 to 17 days. The average lengthTrusted Source is 14 days.  If you do get pregnant, your body will produce human chorionic gonadotropin (hCG). This is the hormone pregnancy tests detect. It helps maintain the corpus luteum and keeps the uterine lining thick. If you don’t get pregnant, the corpus luteum will shrink away and be resorbed. This leads to decreased levels of estrogen and progesterone, which causes the onset of your period. The uterine lining will shed during your period. Figure 46.12ba Ovary Ruptured Primary follicle oocyte within follicle Ovulated secondary Growing oocyte follicle Corpus luteum Mature follicle Degenerating corpus luteum Hormones Govern the Menstrual and Ovarian Cycles Figure 46.13b (b) Pituitary gonadotropins in blood 6 LH FSH 3 FSH and LH stimulate LH surge triggers follicle to grow ovulation (c) Ovarian cycle 7 8 Growing follicle Corpus Degenerating Maturing luteum corpus luteum follicle Follicular phase Ovulation Luteal phase Days 0 5 10 14 15 20 25 28 Figure 46.13c Estradiol secreted Progesterone and 4 by growing follicle in estradiol secreted increasing amounts by corpus luteum (d) Ovarian hormones Peak causes in blood LH surge (see 6 ) 5 10 Estradiol 9 Progesterone Estradiol level Progesterone and estra- very low diol promote thickening of endometrium (e) Uterine (menstrual) cycle Endometrium (e) Menstrual flow phase Proliferative phase Secretory phase Days 0 5 10 14 15 20 25 28 During the Menstrual Cycle, an Oocyte Is Released from an Ovary Menarche First menstruation: between ages of 10 and 16 Menopause Cessation of menstruation; fertility ceases; generally between late 40s and early 50s Temporary symptoms of decline of estrogens Endometrosis Tissue spreads and grows outside of the uterus; leads to scarring; symptoms and treatment  Fertilization Unites a Sperm and Oocyte Gonads Produces Gametes — Cells That May Unite for Sexual Reproduction Germ cells Produce sperm or eggs (gamete) Fertilization Sperm enters a secondary oocyte → zygote Changes necessary in the sperm to enter the egg Capacitation: acrosome membrane is weakened Many sperm bind to the oocyte Oocyte’s membrane changes; only one sperm enters; meiosis II of the oocyte is completed Ovum: nuclei of mature egg and sperm fuse Conception, Embryonic Development, and Birth Conception, fertilization of an egg by a sperm, occurs in the oviduct The resulting zygote begins to divide by mitosis in a process called cleavage Division of cells gives rise to a blastocyst, a ball of cells with a central cavity © 2011 Pearson Education, Inc. Figure 46.15 3 Cleavage 4 Cleavage continues Ovary 2 Fertilization Uterus 5 Implantation 1 Ovulation Endometrium (a) From ovulation to implantation Endometrium Inner cell mass Cavity Blastocyst Trophoblast (b) Implantation of blastocyst Figure 46.17 (a) 5 weeks (b) 14 weeks (c) 20 weeks  After blastocyst formation, the embryo implants into the endometrium The embryo releases human chorionic gonadotropin (hCG), which prevents menstruation Pregnancy, or gestation, is the condition of carrying one or more embryos in the uterus Duration of pregnancy in other species correlates with body size and maturity of the young at birth © 2011 Pearson Education, Inc.  Twins form in one of two ways: Identical twins occur when a single fertilized egg splits into two. Identical twins look almost exactly alike and share the exact same genes. Most identical twins happen by chance. Identical twins are formed from the splitting of one embryo. They are also known as ‘monozygotic twins’. There are different types of identical twins, depending on what they share in the womb. 1. Almost one third of identical twins have their own placenta, inner membrane, and outer membrane. The medical term for these twins is ‘dichorionic diamniotic’ or DCDA twins. 2. Almost two-thirds of identical twins share the same placenta and chorion, but have their own amnion. These are ‘monochorionic diamniotic’ or MCDA twins. The rest — only about 4% of identical twins — share everything, and are called ‘monochorionic monoamniotic’ (MCMA) twins. 3. Although identical twins are the same sex and are genetically identical, they can develop quite different personalities. You can find a good description of the different types of monozygotic twins, Fraternal twins occur when two, separate eggs are fertilized by two, separate sperm. Fraternal twins do not share the exact same genes — they are no more alike than they are to their siblings from different pregnancies. Fraternal twins tend to run in some families. Multiple births can be fraternal, identical, or a combination. Multiples associated with fertility treatments are mainly fraternal. Identical twins who share the same placenta and chorion can sometimes share a condition called twin–twin transfusion syndrome (TTTS). In this condition, blood flows from one twin to the other, resulting in one baby getting too much blood and the other baby not getting enough. This affects the health of both babies, sometimes severely. Most identical twins don’t get TTTS. But if they do, it is more likely to happen to MCDA twins than to MCMA twins. In vitro fertilization (IVF) is the joining of a woman's egg and a man's sperm in a laboratory dish. In vitro means outside the body. Fertilization means the sperm has attached to and entered the egg. There are five basic steps to IVF: Step 1: Stimulation, also called super ovulation - Medicines, called fertility drugs, are given to the woman to boost egg production. - Normally, a woman produces one egg per month. Fertility drugs tell the ovaries to produce several eggs. - During this step, the woman will have regular USG to examine the ovaries and blood tests to check hormone levels. Step 2: Egg retrieval - A minor surgery, called follicular aspiration, is done to remove the eggs from the woman's body. - The surgery is done in the doctor's office most of the time. - The woman will be given medicines so she does not feel pain during the procedure. The needle is connected to a suction device, which pulls the eggs and fluid out of each follicle, one at a time. - The procedure is repeated for the other ovary. There may be some cramping after the procedure, but it will go away within a day. - In rare cases, a pelvic laparoscopy may be needed to remove the eggs. If a woman does not or cannot produce any eggs, donated eggs may be used. Step 3: Insemination and Fertilization - The man's sperm is placed together with the best quality eggs. The mixing of the sperm and egg is called insemination. - Eggs and sperm are then stored in an environmentally controlled chamber. The sperm most often enters (fertilizes) an egg a few hours after insemination. - If the doctor thinks the chance of fertilization is low, the sperm may be directly injected into the egg. This is called intracytoplasmic sperm injection (ICSI). - Many fertility programs routinely do ICSI on some of the eggs, even if things appear normal. Step 4: Embryo culture - When the fertilized egg divides, it becomes an embryo. Laboratory staff will regularly check the embryo to make sure it is growing properly. Within about 5 days, a normal embryo has several cells that are actively dividing. - Couples who have a high risk of passing a genetic (hereditary) disorder to a child may consider pre- implantation genetic diagnosis (PGD). - The procedure is most often done 3 to 5 days after fertilization. Laboratory scientists remove a single cell or cells from each embryo and screen the material for specific genetic disorders. Step 5: Embryo transfer - Embryos are placed into the woman's womb 3 to 5 days after egg retrieval and fertilization. - The procedure is done in the doctor's office while the woman is awake. The doctor inserts a thin tube (catheter) containing the embryos into the woman's vagina, through the cervix, and up into the womb. If an embryo sticks to (implants) in the lining of the womb and grows, pregnancy results. - More than one embryo may be placed into the womb at the same time, which can lead to twins, triplets, or more. The exact number of embryos transferred is a complex issue that depends on many factors, especially the woman's age. - Unused embryos may be frozen and implanted or donated at a later date. Contraception Sexual transmitted disease LEARNING OBJECTIVE 3. To understand how to taking care reproductive organs and how to prevent sexual transmitted disease Both Men and Women May Opt for Surgical Methods of Birth Control Sexually Transmitted Diseases  Gonorrhea May Have No Symptoms at First Caused by Neisseria gonorrhoeae (gonococcus) Many unreported cases Can spread to PID in women Antibiotic resistance Syphilis Eventually Affects Many Organs Caused by Treponema pallidum Develops in stages Tertiary stage may appear 5–20 years after initial infection; prognosis is not good in this stage STDs Caused by Viruses and Parasites Focus: Viruses, parasites, and other pathogens also cause disorders that can be transmitted by sexual contact.  HIV “Human Immunodeficiency Virus” A specific type of virus (a retrovirus) HIV invades the helper T cells to replicate itself. No Cure  AIDS Acquired Immunodeficiency Syndrome HIV is the virus that causes AIDS Disease limits the body’s ability to fight infection A person with AIDS has a very weak immune system No Cure Genital Herpes Is a Lifelong Infection Caused by Herpes simplex virus Type I (infects the lips, tongue, mouth, and eyes) Type 2 (genital infections) No cure: latent and then recurrences Triggers for flare-ups  Human Papillomavirus Can Lead to Cancer Genital warts Painless growths in the genital region Extremely contagious Caused by human papillomavirus (HPV) May cause cervical cancer Pap smear recommended Anti-HPV vaccine Parasites Cause Some STDs Pubic lice: arachnid Crabs Candidiasis: caused by Candida albicans Yeast infection Trichomoniasis: caused by Trichomonas vaginalis protozoan Animal Parasites Also Cause STDs