Fertilisation and Contraception

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Fertilisation and contraception Learning objectives 1. To know the terms fertilisation and contraception 2. To understand the process of fertilisation in human beings 3. PSHE: To be able to explain how strong emotions can have positive and negative effects on the way we all make decisions and choices Key words: Name as many key words associated with fertilisation and contraception as you can think of. Link - starter Link - starter Link - starter Link - starter Achieve – Main task KEY POINTS -Fertilisation happens when an egg cell meets with a sperm cell and joins with it. -This happens after sexual intercourse in which a man puts his penis into the woman's vagina. -Sperm cells travel in semen from the penis and into the Main task Main top of the vagina. – - - They enter the uterus through the cervix and travel to the egg tubes. - If a sperm cell meets with an egg cell there, fertilisation can happen. Achieve Achieve TASK • Examples of contraceptive methods have been placed around the room • Your task is to explore the room and complete the worksheet identifying ‘How each type of contraceptive works’ THINK ABOUT WHERE IN THE REPRODUCTIVE PROCESStask Main THE METHOD ACTS – • Gold: What are the advantages of each different method of contraception. Use this to write a PEE chain justifying which you think is the best method of contraception Achieve Achieve Point: I think that the best method of contraception is.. Evidence: Demonstrate Explain: – Review Review What makes a good parent? Find out in S1 in your next session Next lesson..... Next Extra Slides Sex cells - Sperm In males the sex cells are called sperm. Sperm are produced in sex organs called testes. Nucleus containing Cell membrane chromosomes Head Tail Middle piece Sex cells - Egg In females the sex cells are called eggs. Eggs are produced in sex organs called ovaries. Nucleus containing cytoplasm chromosomes membrane jelly coat An egg is so big that this is how big a sperm looks next to it. Sperm or Egg? Both sperm and eggs have special features that makes it possible for them to carry out their jobs. Look at the statements on the next page and decide which one you think belongs to an egg and which one belongs to a sperm. Once you think you know push the buttons to see if you are right. Sperm or Egg?.

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Fertilisation and Moral Status: a Scientific Perspective
Journal ofmedical ethics, 1987, 13, 173-178 J Med Ethics: first published as 10.1136/jme.13.4.173 on 1 December 1987. Downloaded from Fertilisation and moral status: a scientific perspective Karen Dawson Monash University, Australia Author's abstract begins with a spermatozoon, the male gamete, The debate about the moral status ofthe embryo hasgained penetrating the ovum or female gamete and culminates new impetus because of the advances in reproductive in the mingling of the genetic material from each to technology that have made early human embryo form a single-celled zygote. experimentation a possibility, and because of the public Historically, fertilisation was believed to be possible concern that this arouses. Severalphilosophical arguments only in the uterine or fallopian tubes of the female, claiming that fertilisation is the event that accords moral but recent medical advances resulting in many births status to the embryo were initiallyformulated in the context world-wide, have demonstrated that in vitro of the abortion debate. Were they formulated with fertilisation is also possible (3). Regardless of the sufficientprecision to accountforthe scientificfacts as we location of the process, its biological consequences are now understand them? Or do these arguments need the same: fertilisation restores the diploid chromosome three moralstatus number, enhances genetic variation, results in sex modification?Aspects of argumentsfor copyright. beingacquired atfertilisation are examined in relation to determination and is a necessary prerequisite for current scientific knowledge, highlighting the reasons why embryogenesis to proceed (4). such arguments, atpresent, seem toprovide an inadequate basis for the determination of moral status. Fertilisation and moral status: the arguments examined Advances in reproductive technology have made it technically possible for the early human embryo to be Arguments in support of fertilisation as the time at an experimental subject.
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Section 6: Sex Cells and Fertilisation
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Sex-Specific Spawning Behavior and Its Consequences in an External Fertilizer
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The Protection of the Human Embryo in Vitro
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KS3 Science: Year 7 Module Five: Reproduction, Acids and Alkalis, Light
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Iodine Compounds and Fertilisation Iv
238 IODINE COMPOUNDS AND FERTILISATION IV. CAPACITY FOR FERTILISATION IN WASHED AND UNRIPE EGGS OF ECHINUS ESCULENTUS AND ECHINUS MILIARIS BY G. S. CARTER, Corpus Christi College, Cambridge. (From the Laboratory of Experimental Zoology, Cambridge, and the Marine Laboratory, Millport.) (Received 16th December, 1931.) WASHED EGGS. IT has been shown (Carter, 1931 b) that eggs of Echinus escidentus and E. miliaris which are being washed in a current of sea-water remain fertilisable for a longer time if thyroxine is present in the water of the current. In his investigation of the egg secretions and the part they play in the fertilisation of the egg, Lillie (1914) showed that the rapid decay of echinoderm eggs exposed to a current of sea-water is due to the diffusion of the secretions from the surface of the eggs, and particularly to the loss of one component of the secretions which is essential to the activation of the eggs ("fertilizin"). In view of his work, the results of the previous paper strongly suggest that the manner in which thyroxine acts in prolonging the life of washed eggs is by penetrating the surface of the eggs and causing a change in the cytoplasm by means of which the supply of fertilizin within the egg is main- tained for a longer time. The probability that it acts in this way is increased by the evidence given in the earlier papers of this series (1930, 1931 a), where it was shown that the egg secretions and thyroxine act so similarly in other phenomena that it is probable that thyroxine is chemically related to some substance present in the secretions.
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Mammalian Fertilisation Mechanisms
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Report of the Committee of Inquiry Into Human Fertilisation and Embryology
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F(L P)-1 12 DAVID G
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Embryo–Epithelium Interactions During Implantation at a Glance John D
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Mammalian Gametogenesis to Implantation - Elena De La Casa Esperón, Ananya Roy
REPRODUCTION AND DEVELOPMENT BIOLOGY - Mammalian Gametogenesis to Implantation - Elena de la Casa Esperón, Ananya Roy MAMMALIAN GAMETOGENESIS TO IMPLANTATION Elena de la Casa Esperón and Ananya Roy Department of Biology, The University of Texas Arlington, USA Keywords: gametogenesis, germ cells, fertilization, embryo, cleavage, implantation, meiosis, recombination, epigenetic reprogramming, X-chromosome inactivation, imprinting. Contents 1. Introduction 2. Origin and development of germ cells 2.1. Migration of the Primordial Germ Cells towards the Gonad 3. Germ cell-differentiation: Gametogenesis and meiosis 3.1. Meiosis: The Formation of Haploid Gametes 3.1.1. Crossover and Recombination: The Basis of Genetic Variability 3.2. Sexual Dimorphism- Oogenesis vs. Spermatogenesis 3.3. Meiosis Success in Males and Females and Its Consequences 4. The encounter of egg and sperm: fertilization 5. The first days of an embryo: cleavage to blastocyst 6. The first direct interaction with the mother: implantation 7. Preimplantation variations: monozygotic twins, chimeric embryos and transgenic animals 8. The genetics of preimplantation: how early development is regulated from the nucleus 8.1. From Two Gametes’ Nuclei to a New Being: Genome Activation 8.2. Imprinting and Epigenetic Reprogramming: Chromatin Modifications that Separate Parental Genomes and Create Totipotent Cells 8.2.1. X-Chromosome Transcription: Inactivation and Reactivation 9. Conclusions and future perspectives Glossary Bibliography Biographical Sketches Summary UNESCO – EOLSS The origin of new live beings and the events that occur before birth have been the object of fascination andSAMPLE discussion over the centu ries.CHAPTERS Our concept of two cells, ovum and sperm, fusing to generate a zygote, then an embryo and finally a new individual, is relatively new; as it is the idea of two sets of chromosomes carrying the genetic information inherited from each parent and being coordinated to generate something new and different.
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