DOCSLIB.ORG

Human Reproduction

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Human Reproduction Sexual Health Education Grade 5 Human Reproduction Grade 5 Lesson 4 National Sexuality Education Standards: State Standards: Describe male and female reproductive Goal 22: Understand principles of health systems including body parts and their promotion and the prevention and treatment functions. AP.5.CC.1 of illness and injury. Describe the process of human reproduction. Goal 23: Understand human body systems and PR.5.CC.1 factors that influence growth and development. Goal 24: Promote and enhance health and well-being through the use of effective communication and decision-making skills. Common Core Alignment: CCSS.ELA-Literacy.SL.5.1 Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade 5 topics and texts, building on others' ideas and expressing their own clearly. CCSS.ELA-Literacy.SL.5.2 Summarize a written text read aloud or information presented in diverse media and formats, including visually, quantitatively, and orally. CCSS.ELA-Literacy.L.5.4 Determine or clarify the meaning of unknown and multiple-meaning words and phrases based on grade 5 reading and content, choosing flexibly from a range of strategies. Rationale: This lesson introduces many new and unfamiliar vocabulary words related to human reproduction. Students will learn these new words in a quiz format using a word bank. Information will be presented visually and orally during the discussion on reproduction, and students will have to integrate new information from a variety of sources. Time Requirements Day 1 30 minute introduction and video 10 minute discussion Day 2 20 minute lesson 20 minute activity Lesson Objectives Students will identify the different parts of the male and female reproductive system. Students will define the functions of the different parts of the male and female reproductive system. Sexual Health Education Grade 5 Students will describe the fertilization process. Students will identify the requirements for pregnancy to occur. Students will identify when a female can become pregnant. Vocabulary See 5th Grade Vocabulary List located in the 5th grade folder. Materials It’s Not the Stork by Robie H. Harris (optional) –pages 28-43 presents topics covered in this lesson through child friendly words and pictures. Teachers may choose to read aloud from It’s Not the Stork prior to beginning this lesson to introduce topics of sex and reproduction. Available at Chicago Public Libraries or available for checkout in English and Spanish from the Office of Student Health and Wellness by contacting [email protected]. Human Reproduction and Childbirth (film) – Available on Safari Montage or available for checkout from the Office of Student Health and Wellness by contacting [email protected]. Teacher’s Note: If Safari Montage is not available and the video is not available from OSHW, use the Human Reproductive Systems PowerPoint and/or the Labeled Male and Female Reproductive Systems diagrams (as detailed on Day 2) to meet lesson standards and objectives. Question box Human Reproductive Systems PowerPoint and/or Labeled Male and Female Reproductive Systems diagrams Human Reproduction Activity Sheet Human Reproduction Student Packet Human Reproduction Student Packet Matching Answer Key Construction paper Glue Preparation Review Human Reproductive Systems PowerPoint and/or print Labeled Male and Female Reproductive Systems diagrams Cut out stories from the Human Reproduction Activity Sheet-1 per class (Each student group will have a story. Larger classes can repeat stories.) Print Human Reproduction Student Packet – 1 per student Review Human Reproduction Student Packet Answer Key Key Content Humans reproduce through sexual reproduction, specifically via vaginal intercourse. Sexual Health Education Grade 5 Pregnancy requires an egg from the female, a sperm from the male, and implantation of the zygote in the lining of the uterus. A female can become pregnant as soon as she begins ovulating. The ability to produce sperm or the beginning of ovulation does not make an individual ready to become a parent. Activity Day 1 The Giggle Minute: Students (and teachers!) may be uncomfortable with the medically-accurate words contained within this lesson. Acknowledge this discomfort with students and affirm that it’s ok to feel that way. However, it is important to learn the correct words for all body parts and functions so that they can talk about their bodies with confidence. Give students a “giggle minute”, or the chance to get laughter out at the beginning of the lesson. Refer to Giggle Minute directions located in the Classroom Tools folder for further instruction 1.) Introduction Explain: Over the past several lessons, we have learned about the ways that bodies going through puberty prepare for physical maturity and adulthood. All of the physical changes that we have learned about are the steps the body takes that are needed to allow female and male bodies to reproduce. Review (briefly) physical changes of puberty in the male and female bodies. Say: “Humans reproduce through sexual contact. You may have heard the phrases “having sex” or “making love”. There are many different kinds of sexual contact, but the kind of sexual contact needed for reproduction is called vaginal intercourse or vaginal sex. Vaginal intercourse is when the male places his erect penis into a woman’s vagina. The male then ejaculates, releasing sperm into the vagina, where it may meet with an egg and cause pregnancy.” 2.) Human Reproduction and Childbirth Sexual Health Education Grade 5 Show: Human Reproduction and Childbirth (22 minutes) – Available on Safari Montage or for checkout by contacting the Office of Student Health and Wellness at [email protected]. Teacher’s Note: If Safari Montage is not available and the video is not available from OSHW, use the Human Reproductive Systems PowerPoint and/or the Labeled Male and Female Reproductive Systems diagrams (as detailed on Day 2) to meet lesson standards and objectives. Discuss: . What are the four things needed for pregnancy? Egg, sperm, fertilization and implantation . Who can get pregnant? A sperm and an egg are needed in order for a person to be pregnant. If a person is not able to get pregnant through vaginal intercourse there are other options for them. A person would need to visit a special doctor to find out about these options that include artificial insemination or in-vitro fertilization. A person who is not able to have a baby can also look into adopting a child. At what age can a female get pregnant? It’s different for everyone! Most females who are producing eggs can become pregnant. Emphasize that a girl has to have begun puberty and begun releasing an egg (ovulating). She may become pregnant before she gets her first period, as she cannot tell when her body will begin ovulation. When can a female get pregnant? Anytime her body releases an egg (ovulates). Though this happens about once a month, the female cannot tell which days of the month there will be an egg in her fallopian tubes. Any time there is vaginal intercourse a female could become pregnant. Who can become a parent? A woman who has a baby (natural pregnancy, in-vitro fertilization, artificial insemination), a father of a child, or someone who adopts or cares for a child. Emphasize, just because a person can provide the sperm or egg for a pregnancy does NOT mean they are ready to become a parent. Some people may choose never to have a baby and that’s ok too! Fast Fact: Sometimes the genetic material creates multiple fetuses – twins. This happens in two ways: . Identical twins: occur when a single fertilized egg splits in two. Identical twins have the same genetic material and look exactly the same. Identical twins happen by chance. 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. See slides from grade 6 Lesson 2 – Pregnancy and Birth for visual aid. Sexual Health Education Grade 5 Answer student questions about the video. Encourage students to write down additional questions and place them in the anonymous question box. Plan time to answer questions from the question box within the two days of this lesson. Day 2 3.) Female Reproductive Anatomy and Male Reproductive Anatomy Distribute “Human Reproduction Packet” to students. Project the Labeled Female Reproductive System diagram or use the Human Reproductive PowerPoint. Review female body parts, definitions and functions. Use the projected images and track the path of the egg as it released from the ovary. Describe what happens if sperm is present and pregnancy occurs. Describe what happens if there is no sperm present and pregnancy does not occur (menstruation occurs and the egg dissolves and exits the body) Students should label the parts of the female reproductive system in their packet. Repeat for Male Reproductive Anatomy Project the Labeled Male Reproductive Systems diagram or use the Human Reproductive PowerPoint. Track the path of the sperm from its source of origin in the testes through ejaculation. Students should label part of the male reproductive system in their packet. 4.) Activity #1: The Story of the Egg and Sperm Divide students into groups of 4-5. Provide each group with one of the following scenarios; “Story of the Egg – Pregnancy”, “Story of the Egg – Without pregnancy”, or “Story of the Sperm”, glue, scissors, and construction paper Student groups should assemble the story in the correct order and glue them to a construction paper backing. Check student work before they glue to construction paper. Choose one student group per story to share their work with the class. 5.) Homework Students will complete the Matching Quiz worksheet in their packet.
Load more

Recommended publications
  • Puberty in Girls: Discussing Masturbation
    PUBERTY IN GIRLS: DISCUSSING MASTURBATION Discussing masturbation is an anxiety-provoking moment for any parent. It is important to address the topic with your daughter in a manner that is consistent with your family’s belief system and to set rules that are both age appropriate and comfortable for you to follow through with. This includes acknowledging that it is normal for your daughter to have sexual urges and interest. A good way to open the conversation is through books that discuss puberty and sexual topics in a frank and straightforward manner. Find out what your daughter already knows. Make sure she knows the different parts of her body and their functions. Consider using picture books or a body puzzle to make a simple game such as “find the body part” to see if your daughter understands what the body parts are and their functions; give her a healthy reward or praise to show her that she has done well. Read books together about puberty/adolescence, OR if your daughter doesn’t want to read with you, make them available to her by placing them in places where she plays. When it comes to discussing masturbation, you will need to be explicit. Because many individuals on the autism spectrum tend to self-stimulate in various ways, boundaries must be set around masturbation. Teach rules for appropriate time and place, and tell your daughter that sometimes masturbation is not an option. Provide her with private time where she will be undisturbed. Establish an open dialogue with your daughter about sexuality, which includes being safe and socially appropriate.
    [Show full text]
  • Human Reproduction and Childbirth
    8083DV HUMAN REPRODUCTION AND CHILDBIRTH DVD Version ISBN-13: 978-1-55548-681-5 ISBN: 1-55548-681-9 HUMAN REPRODUCTION AND CHILDBIRTH CREDITS Executive Producer Anson W. Schloat Producer Peter Cochran Script Karin Rhines Teacher’s Resource Book Karin Rhines Former Program Director, Westchester County (NY) Department of Health Copyright 2009 Human Relations Media, Inc. HUMAN RELATIONS MEDIA HUMAN REPRODUCTION AND CHILDBIRTH HUMAN REPRODUCTION AND CHILDBIRTH TABLE OF CONTENTS DVD Menu i Introduction 1 Learning Objectives 2 Program Summary 3 Note to the Teacher 4 Student Activities 1. Pre/Post Test 5 2. Male Anatomy 7 3. Female Anatomy 8 4. Comparative Anatomy 9 5. Matching Quiz 12 6. What Happens When? 14 7. The Fertilization Process 17 8. Care Before Birth 19 9. Research Project 20 10. Being a Parent 22 11. Stem Cells 23 Fact Sheets 1. The Menstrual Cycle 24 2. The Production of Sperm 26 3. Prenatal Care 27 4. Fetal Development 28 5. Screening Newborns for Inherited Diseases 31 6. Prenatal Pictures 32 7. Eating for Two 33 8. Fetal Alcohol Syndrome 35 9. What About Multiples? 36 10. Resources 38 11. Bibliography 39 Other Programs from Human Relations Media 40 HUMAN RELATIONS MEDIA HUMAN REPRODUCTION AND CHILDBIRTH HUMAN REPRODUCTION AND CHILDBIRTH DVD MENU MAIN MENU PLAY CHAPTER SELECTION From here you can access many different paths of the DVD, beginning with the introduction and ending with the credits. 1. Introduction 2. The Male Reproductive System 3. The Female Reproductive System 4. Fertilization and Pregnancy 5. First Trimester 6. Second and Third Trimester 7.
    [Show full text]
  • Original Article HISTOLOGICAL CHARACTERISTICS of FOLLICULOGENESIS in MURRAH WATER BUFFALOES DURING the EARLY POSTPUBERTAL PERIOD
    Bulgarian Journal of Veterinary Medicine, 2020, 23, No 1, 8088 ISSN 1311-1477; DOI: 10.15547/bjvm.2156 Original article HISTOLOGICAL CHARACTERISTICS OF FOLLICULOGENESIS IN MURRAH WATER BUFFALOES DURING THE EARLY POSTPUBERTAL PERIOD V. MANOV, V. PLANSKI & G. S. POPOV Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria Summary Manov, V., V. Planski & G. S. Popov, 2020. Histological characteristics of folliculogenesis in Murrah water buffaloes during the early postpubertal period. Bulg. J. Vet. Med., 23, No 1, 8088. A characteristic feature of water buffalo heifers is that they approach breeding maturity later than bovine heifers. From a physiological and endocrinological view, this is related to a later puberty, which affects the overall reproductive performance of water buffalo. The aim of this study was to highlight some morphological characteristics of the water buffalo (Bubalus bubalis) ovaries in the early postpubertal period. The results showed active ovaries of the examined specimens. Some of the follicles had no oocyte, but were with normal structure and physiological activity. Histology is a de- finitive method for examination of ovarian activity in water buffaloes. In some of the ovulating folli- cles the oocyte was absent during early puberty. The presence of corpora lutea confirmed the endo- crine maturity of the hypothalamus-pituitary-gonadal endocrine axis in 11–14 months old heifers despite the absence of oocytes. Key words: corpus luteum, estrus, follicle, ovary, ovulation, postpubertal period, water buffalo heifer INTRODUCTION Water buffalo heifers attain breeding ma- variable and is influenced by a wide vari- turity later than bovine heifers which is ety of factors, including climate, geo- attributed to later onset of puberty, affect- graphic area, breed, season of birth, and ing the overall reproductive performance.
    [Show full text]
  • Puberty—Ready Or Not Expect Some Big Changes
    puberty—ready or not expect some big changes Puberty is the time in your life when your Zits! body starts changing from that of a child to that of an Girls & Boys. adult. At times you may feel like your body is totally Another change that out of control! Your arms, legs, hands, and feet happens during puberty is that your skin gets oilier and you may may grow faster than the rest of your body. You may feel a little start to sweat more. This is because your glands are growing too. clumsier than usual. It’s important to wash every day to keep your skin Compared to your friends you may feel too tall, too short, too clean. Most people use a deodorant or antiperspirant to keep odor fat, or too skinny. You may feel self-conscious about and wetness under control. Don’t be surprised, even if you wash these changes, but many of your friends probably do too. your face every day, that you still get pimples. This is called acne, and it’s normal during this time when your hormone levels are Everyone goes through puberty, but not always at high. Almost all teens get acne at one time or another. the same time or exactly in the same way. In general, here’s Whether your case is mild or severe, there are things you can do what you can expect. to keep it under control. For more information on controlling acne, talk with your pediatrician. When? There’s no “right” time for puberty to begin.
    [Show full text]
  • Knowledge About Human Reproduction and Experience of Puberty 4
    KNOWLEDGE ABOUT HUMAN REPRODUCTION AND EXPERIENCE OF PUBERTY 4 4.1 KNOWLEDGE AND EXPERIENCE OF PUBERTY Knowledge of the physiology of human reproduction and the means to protect oneself against sexual or reproductive problems and diseases should be available to adolescents. Better knowledge of these subjects among young adults will lead to correct attitudes and responsible reproductive health behavior. 4.1.1 Knowledge of Physical Changes In the 2002-2003 Indonesia Young Adult Reproductive Health Survey (IYARHS), respondents were asked several questions to measure their knowledge about human reproduction and the experience of puberty. They were asked to name any physical changes that a boy or a girl goes through during the transition from childhood to adolescence. The responses were spontaneous, without any prompting from the interviewer. The findings are presented in Table 4.1. It is interesting to note that while the respondents may have experienced some of the physical changes listed in the questionnaire, some may not have recognized them as part of the process of growing up into adulthood; others may not report them to the interviewer. Table 4.1 Knowledge of physical changes at puberty Percentage of unmarried women and men age 15-24 who know of specific physical changes in a boy and a girl at puberty, by age, IYARHS 2002-2003 Women Men Indicators of physical changes 15-19 20-24 Total 15-19 20-24 Total In a boy Develop muscles 26.3 27.7 26.8 33.1 30.4 32.0 Change in voice 52.2 65.6 56.7 35.5 44.6 39.2 Growth of facial hair, pubic hair,
    [Show full text]
  • REVIEW Physiological Dependence on Copulation in Parthenogenetic Females Can Reduce the Cost of Sex
    ANIMAL BEHAVIOUR, 2004, 67, 811e822 doi:10.1016/j.anbehav.2003.05.014 REVIEW Physiological dependence on copulation in parthenogenetic females can reduce the cost of sex M. NEIMAN Department of Biology, Indiana University, Bloomington (Received 6 December 2002; initial acceptance 10 April 2003; final acceptance 27 May 2003; MS. number: ARV-25) Despite the two-fold reproductive advantage of asexual over sexual reproduction, the majority of eukaryotic species are sexual. Why sex is so widespread is still unknown and remains one of the most important unanswered questions in evolutionary biology. Although there are several hypothesized mechanisms for the maintenance of sex, all require assumptions that may limit their applicability. I suggest that the maintenance of sex may be aided by the detrimental retention of ancestral traits related to sexual reproduction in the asexual descendants of sexual taxa. This reasoning is based on the fact that successful reproduction in many obligately sexual species is dependent upon the behavioural, physical and physiological cues that accompany sperm delivery. More specifically, I suggest that although parthenogenetic (asexual) females have no need for sperm per se, parthenogens descended from sexual ancestors may not be able to reach their full reproductive potential in the absence of the various stimuli provided by copulatory behaviour. This mechanism is novel in assuming no intrinsic advantage to producing genetically variable offspring; rather, sex is maintained simply through phylogenetic constraint. I review and synthesize relevant literature and data showing that access to males and copulation increases reproductive output in both sexual and parthenogenetic females. These findings suggest that the current predominance of sexual reproduction, despite its well-documented drawbacks, could in part be due to the retention of physiological dependence on copulatory stimuli in parthenogenetic females.
    [Show full text]
  • Puberty in Boys: from Physical Changes to Masturbation
    PUBERTY IN BOYS: FROM PHYSICAL CHANGES TO MASTURBATION Boys grow and develop (both mentally and physically) at different rates and ages. It is important to know when the “right” time is to begin talking with your son about his development. Ideally, you should begin introducing your son to his body, including his genitals, at an early age. Then, when it is time to talk about the sexual function of his body, it may not be as difficult. Use your judgment in determining when your son is ready for a conversation about puberty and sexuality. For many boys, this may be around age 9 to 11. Keep in mind that it may be earlier or later, depending on your child’s development. Whatever the age, it is important to think about where to begin. Find out what your son knows. Does he already know the body parts? Does he know what it means to have an erection? Use visuals such as drawings and pictures, or use a hand held mirror to help find out if he can name his body parts and genitals and tell you the function of each part. When talking with your son about his body, use the proper or real names of each body part, instead of just saying “down there.” Also teach your son the slang terms for male and female body parts; he is likely to hear them at school or elsewhere. Keep it SIMPLE. For example: “This is your penis: this is where the urine/pee comes out when you use the toilet.” “This is your anus: this is where the stool/poop comes out after your food has been digested.” “This is your penis: this is where semen comes out when you ejaculate.” Be POSITIVE and tell him that his body will grow taller, his testicles and penis will grow bigger, and hair will grow under his arms and in his groin area and that it is NORMAL.
    [Show full text]
  • Female Tanner Stages (Sexual Maturity Rating)
    Strength of Recommendations Preventive Care Visits – 6 to 17 years Bold = Good Greig Health Record Update 2016 Italics = Fair Plain Text = consensus or Selected Guidelines and Resources – Page 3 inconclusive evidence The CRAFFT Screening Interview Begin: “I’m going to ask you a few questions that I ask all my patients. Please be honest. I will keep your Screening for Major Depressive Disorder -USPSTF answers confidential.” Age 12 years to 18 years 7 to 11 yrs No Yes Part A During the past 12 months did you: Screen (when systems in place for diagnosis, treatment and Insufficient 1. Drink any alcohol (more than a few sips)? □ □ follow-up) evidence 2. Smoked any marijuana or hashish? □ □ Risk factors- parental depression, co-morbid mental health or chronic medical 3. Used anything else to get high? (“anything else” includes illegal conditions, having experienced a major negative life event drugs, over the counter and prescription drugs and things that you sniff or “huff”) □ □ Tools-Patient Health Questionnaire for Adolescent(PHQ9-A) Tools For clinic use only: Did the patient answer “yes” to any questions in Part A? &Beck Depression Inventory-Primary Care version (BDI-PC) perform less No □ Yes □ well Ask CAR question only, then stop. Ask all 6 CRAFFT questions Treatment-Pharmacotherapy – fluoxetine (a SSRI) is Part B Have you ever ridden in a CAR driven by someone □ □ efficacious but SSRIs have a risk of suicidality – consider only (including yourself) who was ‘‘high’’ or had been using if clinical monitoring is possible. Psychotherapy alone or alcohol or drugs? combined with pharmacotherapy can be efficacious.
    [Show full text]
  • Precocious Puberty Children with Spina BiDa and Hydrocephalus May Start Puberty Earlier Than Their Peers
    SBA National Resource Center: 800-621-3141 Precocious Puberty Children with Spina Bida and hydrocephalus may start puberty earlier than their peers. What is Puberty? If major breast development starts before age 8, it is considered early. (Sometimes girls will have some Puberty refers to normal body changes that lead to breast development, with no other signs of puberty. maturity and the ability to have children. Normal puberty This isolated change may be normal.) begins between ages 8 and 12 in girls and between 9 and 14 in boys. Hormones made in the brain control the timing and sequence of puberty. These hormones What are the stages of normal puberty in boys? stimulate other parts of the body to make sex hormones. The usual sequence in boys is: The sex hormones, especially estrogen in girls and testosterone in boys, cause sexual maturation. • The testicles grow larger. • The penis grows larger. What are the stages of normal puberty in girls? • Pubic hair grows. The physical changes seen in puberty are labeled by “Tanner staging.” Stage 1 is child-like (before puberty) • There is a growth spurt.rt. and stage 5 is full maturity. The usual sequence in girls is: • Other body hair grows.s. • Breasts start to develop. If boys show major developmentelopment • Hips widen and a there is a growth spurt that usually before age 9, it is considereddered lasts about three to four years. early. Early puberty in girls or boys is called • Pubic hair grows (three-to-six months after breasts “Precocious Puberty.” develop). • Other body hair grows.
    [Show full text]
  • Alcohol, Caffeine, and Ivf Success Pesticide Residues
    E N V I R O N M E N T A N D R E P R O D U C T I V E H E A L T H ( E A R T H ) S T U D Y N E W S L E T T E R SPRING 2018 | VOL 3 HARVARD T.H. CHAN SCHOOL OF PUBLIC HEALTH, MASSACHUSETTS GENERAL HOSPITAL ALCOHOL, CAFFEINE, AND IVF SUCCESS GREETINGS, Alcohol and caffeine have often been the focus of dietary research We are excited to share our recent findings studies on fertility. Results of these studies have been inconsistent; from the Environment and Reproductive some show benefits while others show no effect or possibly reduced Health (EARTH) Study in our 2018 newsletter! fertility. In the EARTH Study, we found that low to moderate consumption of alcohol and caffeine in the year prior to infertility It has been almost 15 years since the EARTH treatment was not associated with IVF outcomes. Our results suggest Study first began. Thanks to your that women's alcohol intake of less than one alcoholic beverage per participation, we continue to learn more day and caffeine intake below 200mg/day (less than one 12oz cup of about the impact of the environment and coffee per day) in the year prior to IVF did not affect their chances of diet on fertility and pregnancy outcomes successful fertility treatment. We also found that men’s caffeine and among couples recruited from the alcohol consumption did not affect their semen quality (Abadia et al, Massachusetts General Hospital (MGH) Human Reproduction 2017; Karmon et al., Andrology 2017).
    [Show full text]
  • Reproductive Ecology & Sexual Selection
    Reproductive Ecology & Sexual Selection REPRODUCTIVE ECOLOGY REPRODUCTION & SEXUAL SELECTION • Asexual • Sexual – Attraction, Courtship, and Mating – Fertilization – Production of Young The Evolutionary Enigma of Benefits of Asex Sexual Reproduction • Sexual reproduction produces fewer reproductive offspring than asexual reproduction, a so-called reproductive handicap 1. Eliminate problem to locate, court, & retain suitable mate. Asexual reproduction Sexual reproduction Generation 1 2. Doubles population growth rate. Female Female 3. Avoid “cost of meiosis”: Generation 2 – genetic representation in later generations isn't reduced by half each time Male 4. Preserve gene pool adapted to local Generation 3 conditions. Generation 4 Figure 23.16 The Energetic Costs of Sexual Reproduction Benefits of Sex • Allocation of Resources 1. Reinforcement of social structure 2. Variability in face of changing environment. – why buy four lottery tickets w/ the same number on them? Relative benefits: Support from organisms both asexual in constant & sexual in changing environments – aphids have wingless female clones & winged male & female dispersers – ciliates conjugate if environment is deteriorating Heyer 1 Reproductive Ecology & Sexual Selection Simultaneous Hermaphrodites TWO SEXES • Advantageous if limited mobility and sperm dispersal and/or low population density • Guarantee that any member of your species encountered is the • Conjugation “right” sex • Self fertilization still provides some genetic variation – Ciliate protozoans with + & - mating
    [Show full text]
  • Human Reproduction (Chapter- 3)
    NOTES HUMAN REPRODUCTION (CHAPTER- 3) Study the following notes along with the N.C.E.R.T Practice all the diagrams in the practice register Refer to the video link at the end of the notes for a better understanding of the chapter Human beings are sexually reproducing, viviparous organisms with internal fertilization and internal development. The reproductive events in human beings include: - Gametogenesis - It is the formation of gametes through the process of meiosis inside the sex organs, that is, testis in males and ovaries in females. Gametes are called as sperms in males and ova or egg in females. - Insemination- It is the transfer of sperms from the male body into the genital tract of female. - Fertilization- It is the fusion of male and female gametes to form a diploid cell called zygote. - Cleavage- The zygote undergoes cleavage that is mitotic divisions to first form a morula and then the blastocyst. - Implantation- The blastocyst gets partially embedded in the walls of the uterus for attachment and nourishment. - Establishment of placenta- A foeto-maternal connective called Placenta develops for attachment, nutrition, respiration and excretion of embryo. - Embryonic development- The implanted embryo undergoes gastrulation (Establishment of the three primary germ layers) and then organogenesis(Development of various tissues, organs and organ systems) - Development and growth of foetus- There is growth of various parts and Systems of the foetus so that they become fully functional. The foetus is then converted into a young one and the period of total stay of embryo in the body of the mother is called gestation period (Pregnancy) - Parturition- The fully formed young one is delivered outside the mother’s body.
    [Show full text]