PSYC 250 1st Edition Lecture 5 Outline of Last Lecture I. Theories of child developmentII. Psychoanalytic theoriesIII. Cognitive theoriesIV. Behavioral and social cognitive theoriesV. Ecological theoryOutline of Current Lecture II. The Evolutionary PerspectiveIII. Genetic Foundations of DevelopmentIV. Reproductive Challenges and ChoicesV. Heredity and Environment Interaction: The Nature-Nuture debateCurrent LectureII. The Evolutionary Perspective- Natural selection and adaptive behavioro Natural selection is the evolutionary process by which those individuals of a species that are best adapted are the ones that survive and reproduceo Those that do survive and reproduce pass on their characteristics to the next generationo All organisms must adapt to particular places, climates, food sources, and ways oflifeo Adaptive behavior is behavior that promotes an organism’s survival in the naturalhabitat- Evolutionary psychologyo Emphasizes the importance of adaptation, reproduction, and survival of the fittest in shaping behavioro Fit refers to the ability to bear offspring that survive long enough to bear offspring of their owno Natural selection favors behaviors that increase reproductive success-the ability to pass genes to the next generationo David buss has been especially influential in stimulating new interest in how evolution can explain human behaviorThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.III. Genetic Foundations of Development - The Collaborative Geneo Chromosomes: threadlike structures made up of deoxyribonucleic acid, or DNA Has a double helix shape (like a spiral staircase) Contains genetic information o Genes Units of hereditary info Help cells to reproduce themselves and to assemble proteins Proteins are the building blocks of cells and regulate the body’s processes The activity of genes (genetic expression) is affected by their environment Each gene has its own location, its own designated place on a particular chromosome - Genes and Chromosomeso Are not only collaborative but enduringo Get passed from generation to generation and end up in all of the trillion cells in the body- Mitosis, Meiosis, and Fertilizationo All cells in the human body, except the sperm and egg, have 46 chromosomes arranged in 23 pairso Mitosis: cellular reproduction in which the cell’s nucleus duplicates itself with two new cells being formed, each containing the same DNA as the parent cell, arranged in the same 23 pairs of chromosomes o Meiosis: forms eggs and sperm (or gametes); the process by which cells in the reproductive organs duplicate their chromosomes, then divide twice, forming four cells, each with half of the genetic material of the parent cell; by the end of meiosis, each egg or sperm has 23 unpaired chromosomeso Fertilization: process in which an egg and a sperm fuse to creat a single cell calledthe zygote - Sources of variabilityo Combining the genes of two parents in their offspring increase genetic variability in the population The chromosomes in the zygote are not exact copies of those in the mother’s ovaries and the fathers testes  Mutated gene: Permanently altered DNA segments Genotype: A person’s genetic heritage; the actual genetic material Phenotype: the way an individuals genotype is expressed in observable and measurable charactieristics- Dominant-recessive gene principleo When one gene of a pair always exerts its effects, it is dominant, overriding the potential influence of the other gene, call the recessive gene- Sex-Linked Geneso Most mutated genes are recessiveo When a mutated gene is carried on the X chromosome, the result is called X-linked inheritanceo Since males have only one X chromosome, they are more likely than females (who would be carries) to manifest an X-linked disease- Genetic imprintingo Occurs when genes have differing effects depending on whether they are inherited from the mother of fathero A chemical process “silences” one member of the gene pairo Only a small percentage of human genes appear to undergo imprinting o When imprinting goes awry, development is disturbed- Polygenic Inheritanceo Few characteristics reflect the influence of only a single gene or pair of geneso Most are determined by the interaction of many different genes (polygenetically determined)o Gene-gene interaction is increasingly used to describe studies that focus on the interdependence of two or more genes in influencing characteristics, behavior, diseases, and development - Chromosomal Abnormalitieso Sometimes, when a gamate is formed, the sperm and ovum do not have the normal set of 23 chromosomeso Down syndrome: a form of mental and motor retardation and abnormalities of physical features caused by the presence of an extra copy of chromosome 21IV. Reproductive challenges and choices- Prenatal diagnostic testing: a number of tests can indicate whether a fetus is developing normallyo Ultrasound sonographyo Fetal MRIo Chorionic Villus Samplingo Amniocentesiso Maternal blood screeningo Noninvasive prenatal diagnosis (NIPD)o Fetal sex determination - Infertility and Reproductive technologyo Approximately 10-15% of couples in the U.S experience infertility o Defined as the inability to conceive a child after 12 months of regular intercourse without contraceptiono The cause of infertility can rest with the woman or the mano More than 2 million couples seek help every yearo Surgery may correct the cause, hormone-based drugs may improve the probability of having a child- High-Tech assisted reproduction methodso In Vitro Fertilization (IVF): eggs and a sperm are combined in a laboratory dish The creation of families by means of new reproductive technologies raisesimportant questions about the physical and psychological consequences for children  One result of fertility treatments is an increase in multiple births VI. Heredity and Environmental Interaction: The Nature-Nurture debate- Behavior genetics: seeks to discover the influence of heredity and environment on individual differences in human traits and developmento To study the influence on behavior, behavior geneticists often use either twin studies or adoption studies- Twin studies: the behavioral similarity of identical twins is compared with the similaritiesbetween fraternal twins- By comparing groups of identical and fraternal twins, behavior