Week 2: Prenatal Development

Natural Selection

- evolutionary process by which those individuals of a species that are best adapted are the ones, that survive and reproduce
- survivors are better adapted to their world than are the non-survivors (Brooker, 2011)

Adaptive Behavior

is a behavior that promotes an organism's survival in the natural habitat (Johnson & Loslos, 2010).

Evolutionary Psychology

- emphasizes the importance of adaptation, reproduction, and "survival of the fittest" in shaping behavior
- "fit" in this sense refers to the ability to bear offspring that survive long enough to bear offspring of their own
- evolution shapes our physical features, such as body shape and height
- influences how we make decisions, how aggressive we are, our fears, and our mating patterns

David Buss

has been especially influential in stimulating new interest in how evolution can explain human behavior.

Evolution Developmental Psychology

- extended childhood period evolved because humans require time to develop a large brain and learn the complexity of human societies
- psychological mechanisms are domain-specific; e.g. information processing
- evolved mechanisms are not always adaptive in contempart society

Paul Balts

"the benefits conferred by evolutionary selection decrease with age"

Albert Bandura

acknowledges the important influence of evolution on human adaptation.

Bidirectional View

environmental and biological conditions influence each other.

Steven Jay Gould

"In most domains of human functioning biology allows a broad range of cultural possibilities"

Chromosomes

- are thread-like structures made up of deoxyribonucleic acid or DNA
- come in 23 pairs, one member of each pair coming from each parent

DNA

complex molecule with a double helix shape, like a spiral staircase and contains genetic information.

Genes

the units of hereditary information, are short segments of DNA. They direct cells to reproduce themselves and to assemble proteins.

Proteins

are the building blocks of cells as well as the regulators that direct the body's processes.

Mitosis

- the cell's nucleus including the chromosomes duplicates itself and the cell divides
- two new cells are formed, each containing the same DNA as the original cell, arranged in the same 23 pairs of chromosomes

Meiosis

- a cell of the testes or ovaries duplicates its chromosomes but then divides twice, thus forming four cells, each of which has only half of the genetic material of the parent cell
- by the end of meiosis, each egg or sperm has 23 unpaired chromosomes

Fertilization

an egg and a sperm fuse to create a single cell, called a zygote.

Zygote

- the 23 unpaired chromosomes from the egg and the 23 unpaired chromosomes from the sperm combine to form one set of 23 paired chromosomes
- one chromosome of each pair from the mother's egg and the other from the father's sperm.Mutated gene

Identical twins

- monozygotic twins
- develop from a single zygote that splits into two genetically identical replicas, each of which becomes a person

Fraternal twins

- dizygotic twins
- develop from separate eggs and separate sperm, making them genetically no more similar than ordinary siblings

Mutated Gene

a permanently altered segment of DNA, a mistake by cellular machinery, or damage from an environmental agent such as radiation.

Genotype

made up of all of a person's genetic material.

Phenotype

consists of observable characteristics including physical characteristics (such as height, weight, and hair color) and psychological characteristics (such as personality and intelligence).

Dominant-Recessive Genes Principle

- in some cases, one gene of a pair always exerts its effects; it is dominant, overriding the potential influence of the other gene, called the recessive gene
- a recessive gene exerts its influence only if the two genes of a pair are both recessive

X-linked Inheritance

when a mutated gene is carried on the X chromosome.

Males

individuals (gender) who mostly have X-linked diseases because they only have one X chromosome.

Females

individuals (gender) that are known as "carriers" and they usually do not show any signs of the X-linked disease.

Autosomal

diseases related to 23 chromosomes

Genetic Imprinting

occurs when the expression of a gene has different effects depending on whether the mother or the father passed on the gene.

Polygenic Inheritance

- most are determined by the interaction of many different genes
- 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 Abnormalities

occurs when a gamete is formed and the male’s sperm and/or the female's ovum do not have their normal set of 23 chromosomes.

Down Syndrome

- caused by the presence of an extra copy of chromosome 21
- round face, a flattened skull, an extra fold of skin over the eyelids, a protruding tongue, short limbs, and retardation of motor and mental abilities

Klinefelter's Syndrome

- genetic disorder in which males have an extra X chromosome, making them XXY instead of XY
- undeveloped testes, and they usually have enlarged breasts and become tall

Fragile X Syndrome

- results from an abnormality in the X chromosome, which becomes constricted and often breaks
- mental deficiency often is an outcome, but it may take the form of mental retardation, a learning disability, or a short attention span
- occurs more frequently in males than in females, possibly because the second X chromosome in females negates the effects of the other abnormal X chromosome

Turner Syndrome

- chromosomal disorder in females in which either an X chromosome is missing, making the person XO instead of XX, or part of one X chromosome is deleted
- short in stature and have webbed neck, they might be infertile and have difficulty in mathematics, but their verbal ability is often quite good

XYY Syndrome

chromosomal disorder in which the male has an extra Y chromosome.

Gene-linked Abnormalities

- abnormalities produced by harmful genes
- more than 7,000 genetic disorder

Phenylketonuria

- genetic disorder in which the individual cannot properly metabolize phenylalanine, an amino acid
- results from a recessive gene and occurs about once in every 10,000 to 20,000 live births
- excess phenylalanine builds up in the child, producing mental retardation and hyperactivity
- occurs primarily in whites
- treated by a diet that prevents an excess accumulation of phenylalanine
- heredity-environment interaction (the presence of a genetic defect does not inevitably lead to the development of the disorder if the individual develops in the right environment)

Sickle Cell Anemia

- genetic disorder that impair the body's red blood cells
- recessive gene causes the RBC to become a hook-shaped "sickle" - cannot carry oxygen properly and dies quickly
- occurs most often in African Americans

Hemophilia

- prolonged bleeding or oozing following an injury, surgery, or having a tooth pulled
- X-linked recessive pattern

Hemophilia A

- also known as classic hemophilia or factor VIII deficiency
- is the most common type of the condition; 1 in 4,000 to 1 in 5,000 males worldwide are born with this disorder

Hemophilia B

- also known as Christmas disease or factor IX deficiency
- occurs in approximately 1 in 20,000 newborn males worldwide

Tay Sach's Disease

- rare inherited disorder that progressively destroys nerve cells in the brain and spinal cord
- infants with this disorder typically appear normal until the age of 3 to 6 months, when their development slows and muscles used for movement weaken
- affected infants lose motor skills such as turning over, sitting, and crawling
- also develop an exaggerated startle reaction to loud noises
- children with Tay-Sachs disease experience seizures, vision and hearing loss, intellectual disability, and paralysis
- mutations in the HEXA gene
- autosomal recessive pattern

Ultrasound

- parental medical procedure in which high-frequency sound waves are directed into the pregnant woman's abdomen
- the echo from the sounds is transformed into a visual representation of the fetus' inner structures
- no risk to the woman or fetus in this test

Magnetic Resonance Imaging

- uses a powerful magnet and radio images to generate detailed images of the body's organs and structures
- can provide more detailed images than ultrasound
- detect better than sonography such as certain central nervous system, chest, gastrointestinal, genital/urinary, and placental abnormalities

Chorionic Villus Sampling

- prenatal medical procedure in which a small sample of the placenta (the vascular organ that links the fetus to the mother's uterus) is removed
- diagnosis takes about 10 days
- a small risk of limb deformity when used
- done at 10th to 12th weeks of pregnancy

Amniocentesis

- prenatal medical procedure in which a sample of amniotic fluid is withdrawn by syringe and tested for chromosomal or metabolic disorders
- done at 15th and 18th weeks of pregnancy
- may take two weeks for enough cells to grow and test results to be obtained
- brings a small risk of miscarriage: about 1 woman in every 200 to 300 miscarries after this procedure

Maternal Blood Screening

- identifies pregnancies that have an elevated risk for birth defects such as spina bifida and down syndrome
- done at 16th and 18th weeks of pregnancy
- triple screen because it measures three substances in the mother's blood

Noninvasive Prenatal Diagnosis

- mainly focused on the isolation and examination of fetal cells circulating in the mother's blood and analysis of cell-free fetal DNA in maternal plasma
- successfully test for genes inherited from a father that cause cystic fibrosis and Huntington's disease

Infertility

- defined as the inability to conceive a child after 12 months of regular intercourse without contraception
- woman may not be ovulating, she may be producing abnormal ova, her fallopian tubes by which ova normally reach the womb may be blocked, or she may have a disease that prevents implantation of the embryo into the uterus
- man may produce two few sperm, the sperm may lack motility or her may have a block passageway

In Vitro Fertilization

procedure in which eggs and sperm are combined in a laboratory dish.

Adoption

the social and legal process by which a parent-child relationship is established between persons unrelated at birth.

Behavior Genetics

- the field that seeks to discover the influence of heredity and environment on individual differences in human traits and development
- try to figure out what responsible for the differences among people - that is, to what extent do people differ because of differences in genes, environment, or combination of these
- often use either twin or adoption situations

Twin Study

the behavioral similarity of identical twins is compared with the behavioral similarity of fraternal twins.

Adoption Study

investigators seek to discover whether the behavior and psychological characteristics of adopted children are more like those of their adoptive parents, who have provided a home environment, or more like those of their biological parents, who have contributed their herdity.

Heredity Environment Correlations

means that an individual's genes may influence the types of environments to which they are exposed.

Sandra Scarr

- behavior geneticist
- described three ways hereditary and environment are correlated

Passive Genotype-Environment Correlations

occur because biological parents, who are genetically related to the child, provide a rearing environment for the child.

Evocative Genotype-Environment Correlations

occur because a child's characteristics elicit certain types of environment.

Active Genotype-Environment Correlations

occur when children seek out environment that they find compatible and stimulating.

Niche-picking

refers to finding a setting that is suited to one's abilities.

Robert Plomin

has found that shared environment accounts for little of the variation in children's personality or interest.

Gilbert Gottllieb

emphasizes the epigenetic view, which states that development is the result of an ongoing, bidirectional interchange between heredity and the environment.

Gene X Environment Interaction

the interaction of a specific measured variation in the DNA and a specific measure aspect of the environment.

38-40 weeks

average weeks of pregnancy.

Germinal Period

- the period which takes place in the first 2 weeks after conception
- it includes the creation of the fertilized egg (zygote), cell division, and the attachment of the zygote to the uterine wall

Blastocyst

inner layer of cells that develop in the germinal period and later develop into the embryo.

Trophoblast

outer layer of cell that develops in the germinal period and cells provide nutrition and support and support for the embryo.

Implantation

attachment of the zygote to the uterine wall takes place about 11-15 days after conception.

Embryonic Period

- the period of prenatal development which occurs 2-8 weeks after conception
- during this period, the rate of cell differentiation intensifies, support systems for the cells form, and organs appear

Embryo

consists of 3 layers of germ cells.

Endoderm

inner layer of cells, which will develop into the digestive and respiratory systems.

Mesoderm

middle layer, which will become the circulatory system, bones, muscles, excretory systems, and reproductive system.

Ectoderm

outer layer, which will become the nervous system and brain, sensory receptors (ears, nose, eyes), and skin parts (hair and nails),

Amnion

a bag or envelope that contains a clear fluid in which the developing embryo floats.

Umbilical Cord

containing two arteries and one vein that connects the baby to the placenta.

Placenta

consists of a disk-shaped group of tissues in which small blood vessels from the mother and offspring intertwine.

Organogenesis

organ formation that takes place during the first 2 months of prenatal development.

3rd week after conception

the neural tube that eventually becomes the spinal cord forms.

About 21 days

the eyes begin to appear

24 days

the cells for the heart begin to differentiate.

5 to 6 weeks

there should be a heartbeat heard from the ultrasound.

4th weeks

the urogenital system becomes apparent and arm and leg buds emerge, four chambers of the heart take shape, and blood vessels appear.

5th to 8th week

- arms and legs differentiate further
- at this time, the face starts to form but still is not very recognizable
- the intestinal tract develops and the facial structures fuse

8 weeks

the developing organisms weighs about 1/30 ounce and is just over 1 inch long.

Fetal Period

- lasting about seven months
- is the prenatal period between two months after conception and birth in typical pregnancies

First 3 months of pregnancy

delicate period during pregnancy.

Neural Tube

- forms at about 18-24 days after conception
- develops ot of the ectoderm

Neurogenesis

massive proliferation of new immature neurons begins to take place about the fifth prenatal week and continues throughout the remainder of the prenatal period.

Neuronal Migration

- 6-24 weeks after conception
- occurs which involves cells moving outward from their point of origin to their appropriate locations and creating the different levels, structures and regions of the brain.

Teratogen

any agent that can potentially cause a birth defect or negatively alter cognitive and behavioral outcomes.

Teratology

field of study that investigates the causes of birth defects.

Behavioral Teratology

some exposures to teratogens do not cause physical birth defects but can alter the developing brain and influence cognitive and behavioral functioning.

Dose
Genetic Susceptibility
Time of Exposure

factors of a teratogen that influences both the severity of the damage to an embryo or fetus and the type of defect

Prescription Drugs

- antibiotics, such as streptomycin and tetracycline; some antidepressants; certain hormones, such as progestin and synthetic estrogen; and accutane
- there are only a few drugs that are safe for pregnant woman

Nonprescription Drugs

e.g. diets pills and high dosages of aspiring

Psychoactive Drugs

- drugs that act on the nervous system to alter states of consciousness, modify perceptions, and change moods
- include caffeine, alcohol, nicotine, cocaine, methamphetamine, marijuana, and heroin

Fetal Alcohol Spectrum Disorders

are a cluster of abnormalities and problems that appear in the offspring of mothers who dirnk alcohol heavily during pregnancy.

Nicotine

- identified as a risk factor for the development of ADHD
- linked to increased risk of low birth weight in offspring
- preterm births. and low birth weights, fetal and neonatal deaths, respiratory problems, sudden infant death syndrome, and cardiovascular problems are common to infants whose mothers who consume this.

Cocaine

- associated with reduced birth weight, length, and head circumference
- linked to lower arousal, less effective self regulation, higher excitability, and lower quality of reflexes at 1 month of age
- impaired motor development at 2 years of age and a slower rate of growth through 10 years of age
- to deficits in behavioral self-regulation
- to impaired language development and information processing including attention deficits (especially in sustained attention) in preschool and elementary school children
- to increased likelihood of being in a special education program that involves support services

Methamphetamine

- babies are at risk for a number of problems, including high infant mortatility, low birth weight, and developmental and behavioral problems
- memory deficits in children