1. Genetics and Prenatal Development 2

2. Genetic Basics Building Blocks of Life  Chromosomes  DNA  Genes  Genomes L.O. 2.1

3. Genetic Basics Expression of Traits  Genotype-The totality of an individual’s genes  Phenotype-Actual Characteristics  This is what is seen or observed and can include a wide range of things L.O. 2.1

4. Genetic Basics Expression of Traits  Dominant Genes-Expressed characteristics  Recessive Genes-Not expressed, although it is a part of the genotype (genetic background)  Allele-Alternate form of a gene  Dominant-Recessive Inheritance L.O. 2.1

5. Genetic Basics Expression of Traits  Incomplete Dominance  Phenotype influenced primarily but not exclusively by the dominant gene  Polygenic Inheritance  Interaction of multiple genes L.O. 2.1

6. Genetic Basics The Sex Chromosomes  The 23 rd chromosomes pair determine male or female  Males more vulnerable to X- linked recessive disorders L.O. 2.2

7. Genetic Basics Genes and Environment  Behavior Genetics  Estimating influence of genes and environment on development  Utilize twins to understand importance of genetics and tease out environment effects L.O. 2.3

8. Genetic Basics Genes and Environment  Heritability  An estimate of the extent to which genes are responsible for differences among persons within a specific population  Concordance Rates  Percentage that indicates degree of similarity in phenotype among pairs of family members L.O. 2.3

9. The Human Experience Conception and Prenatal Development

10. The Beginning of Life Conception  For conception to occur there must be a released ovum and a sperm.  Ovulation releases the ovum, and if sperm available, fertilization can occur. L.O. 2.7

11. The Germinal Period First 2 Weeks of Life  During the travel from the fallopian tube to the uterus cell division is taking place  Blastocyst  Trophoblast  Embryonic disk L.O. 2.8

12. The Embryonic Period Week 3-Week 8  Key Developments  Embryonic Layers  Ectoderm  Mesoderm  Endoderm L.O. 2.9

13. The Embryonic Period Week 3-Week 8  Key organs and structures are forming including  Heartbeat  Eyes, nose and mouth  Bone development  Arm and leg buds  Digestive system L.O. 2.9

14. The Fetal Period Week 9-Birth  The longest period of prenatal development  Heartbeat can be heard  Movement can be felt  Responds to sounds  Main impediment to viability is lung development L.O. 2.10

15. Prenatal Care Traditional Cultures and Beliefs  Prenatal beliefs are impacted by generational wisdom of the time  These beliefs can include  Avoiding wine  Specific types of meat  Certain types of hot, cold food  Witches  Strong foods L.O. 2.11

16. Prenatal Care Science Driven Prenatal Care  Some current science-driven prenatal methods are derived from traditional cultures which includes massages  Current care can vary by ethnicity and SES  Developing world less likely to receive prenatal care  Current focus on diet, exercise, and teratogens L.O. 2.11

17. Prenatal Care Diet  Two key vitamins are iodine and iron  Iodine deficiency tends to be a bigger issue in developing countries  Iron is necessary for a healthy pregnancy L.O. 2.12

18. Prenatal Care Exercise  Continued physical activity is encouraged during pregnancy  Aerobic exercise encourages good cardiovascular health and positively benefits the fetus  A Non-aerobic exercise called Kegel exercises are also encouraged L.O. 2.12

19. Prenatal Care Teratogens  Teratogens are environmental and bodily conditions that could be harmful  They can include tobacco, alcohol, prescription medications and other drugs  The physical environment could also be a teratogen due to malnutrition or exposure to hazardous chemicals L.O. 2.14

20. Safety sign. Source: http://www.compliancesigns.com

21. Pregnancy Problems

22. Chromosomal Disorders  Chromosomal disorders can occur because of an issue during meiosis  This may cause too many or too few chromosomes in the cells of the zygote  Two types of chromosomal disorders are:  Sex chromosome disorders  Disorder on the 21 st chromosome (Down Syndrome) L.O. 2.13

23. Sex Chromosome Disorders  Sex chromosomal disorder can result from extra X, an extra Y, or only an X and no second chromosome  Common consequences of sex chromosome disorders include:  Cognitive Deficit  Abnormality in reproductive system at puberty L.O. 2.13

24. Down Syndrome Trisomy 21  Identifiable by physical characteristics  Cognitive Deficits  Speech problems  Mental retardation  Social development varies  Lower life expectancy L.O. 2.13

25. Parental Age and Chromosomal Disorder  Chromosomal disorders tend to NOT be passed from parent to child  Relationship between maternal age and chromosomal disorders  There may be a relationship between a father’s age and chromosomal disorders but it isn’t as clear L.O. 2.13

26. Teratogens Timing of Teratogens  Teratogens can impact the developing fetus and embryo at any time  There does appear to be a critical period of prenatal development centered in the embryonic period L.O. 2.14