reproduction, heredity and genetics, and prenatal development

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  • Reproduction, Heredity and Genetics, and Prenatal Development

  • ReproductionProcess by which organisms create more organisms of own kind. Male and female gametes or sex cells: Sperm and ovum create zygote

  • Male Reproductive SystemTestes: produce spermPenis: Mans external organ

  • The Female Reproductive SystemOvaries produce ova.Ovum released approximately every 28 days.Moves through fallopian tubes where it may be fertilized by sperm.Uterus prepares itself for conception.Unfertilized ovum shed; expelled through cervix and vagina.

  • How and When Fertilization OccursMenstrual CycleOvulationFertilizationMultiple Conception

  • Conceiving or Avoiding ConceptionInfertility and Assisted Reproductive TechnologyIn Vitro FertilizationEthical Dilemmas of Baby MakingBirth Control Methods a. Contraception b. Abortion

  • Infertility and Assisted Reproductive TechnologyIn vitro fertilization (IVF)Gamete intrafallopian transfer (GIFT)Zygote intrafallopian transfer (ZIFT)Intracytoplasmic sperm injection (ICSI)Preimplantation genetic treatment (PGT)Ovarian and sperm cryopreservationSperm sorting (sperm separation)Embryo adoption

  • Ethical Dilemmas of Baby MakingARTs have significantly improved pregnancy ratesQuestions:How long should embryos develop in lab?Who do embryos belong to?What type of research is being conducted?

  • Birth Control MethodsAbstinenceContraceptionAbortion

  • The Expanding Reproductive YearsMenstruation can begin at 8 or 9 years of age; average 11 to 12Advanced technology allows women to choose childbearing after menopause.

  • Heredity and GeneticsHeredity: our biological inheritanceGenetics: the scientific study of biological inheritance

  • The Human Genome ProjectThe sequencing of the genetic blueprint of all the genes on their appropriate chromosomesGenome is divided into chromosomesChromosomes contain genesGenes are made of DNA

  • What are Chromosomes and Genes?ChromosomesGenesDNAHuman genomeMitosisMeiosis

  • Determination of an Embryos Sex46 chromosomes (23 pairs) 22 are similar in size and shape in both men and women: autosomes23rd pair: sex chromosome, determines babys sex.

  • Principles of GeneticsGregor Johann MendelDominant and Recessive Characteristics a. Allele (dominant or recessive) b. Homozygous characteristic c. Heterozygous characteristics d. Polygenic inheritance

  • Phenotypes and GenotypesGenotype: Actual genetic makeup of organismPhenotype: Observable characteristics of organism

  • Multifactorial Transmission Environmental factors interact with genetic factors to produce traits.Sex-Linked Inherited Characteristics: Genes that are linked or appear on the same chromosome are inherited together: Sex-linked traits.

  • Genetic Counseling and TestingGenetic Counseling: Helps parents find out risk of passing along a particular disorder or disease.

  • Genetic and Chromosomal AbnormalitiesDowns Syndrome: Occurs in 1 out of every 800 live births.In 95% of all cases there are three copies of the 21st chromosome: trisomy 21Extra chromosome alters course of development and causes physical characteristics.

  • Box: Human DiversityPrenatal diagnosis:AmniocentesisUltrasonographyFetoscopyChorionic villus biopsyMaternal blood sampling

  • Prenatal DevelopmentGerminal Period: From conception to second week.Characterized by growth of zygote and establishment of linkage between zygote and support system of mother.

  • Embryonic PeriodFrom end of second week to eighth week.Rapid growthEstablishment of a placental relationship with motherEarly structural appearance of all chief organsDevelopment of recognizable human body.

  • Development during embryonic period

    Cephalocaudal Proximodistal Critical Period

  • Fetal PeriodBegins with the ninth week and ends with birthCharacteristics: Organism called a fetusMajor organ systems continue to develop and assume their specialized functions.

  • Loss by MiscarriageMiscarriage: organism is naturally expelled from uterus before it is viable.

  • Prenatal Environmental InfluencesTeratogens: Drugs and other chemical agents that can cause birth defects: Smoking Marijuana Hard Drugs Alcohol Oral Contraceptives Toxins in environment and workplace

  • Maternal Infectious and Noninfectious Diseases:

    Rubella and Other AgentsSyphilisGenital HerpesHIV/AIDSDiabetesMaternal Sensitization: The Rh Factor Maternal StressMaternal AgeMaternal Nutrition and Prenatal Care