Developmental Psych: CH 2
Evolutionary Development Psychology
- childhood evolved and is longer now (we develop for a lot of years) in order to give us a larger brain to handle the social complexities of being human. sets us apart from apes. - we crave high fat foods because we evolved from scavenging. -evolution gave us the biological changes to adapt to environment, it doesnt dictate behaviour.
How we see variability between people
- through the genotype and phenotype for each genotype a number of phenotypes can be expressed, and environment effects those potentials (nutrition on height)
Genetic Principles- what determines how a genotype is expressed to create a phenotype?
1. Dominant Recessive Genes Principle 2. Sex Linked Genes 3. Genetic Imprinting 4. Polygenic Inheritance
Crossing Over
During Miosis before a pair separates, pieces of each chromosome are exchanged, creating a new combination of genes on each chromosome. this process is called crossing over. SO, when chromosomes from the egg and sperm are brought together in the zygote, the result is a unique combo of genes.
X-Linked Disease- Inheritance
When a mutated gene is carried on the X chromosome. most mutated genes are recessive. women have two XX chromosomes they are rarely affected because the will use the second one if the first one is damaged. Men are more effected. Females with one changed X are called carriers for the disease. Examples: Hemophilia (thin blood), colour blindness, and fragile-x syndrome.
DNA
a complex molecule that contains genetic information (genes)
Sickle-Cell Anemia
a genetic disorder affects the red blood cells and occurs most often in african ppl. red blood cells carry oxygen to the body's cells and usually shaped like disks. this recessive gene causes red blood cells to become a hook shape that does not receive adequate oxygen. 1/400 babies.
phenylketonuria (PKU)
a genetic disorder individual cannot properly metabolize an amino acid. now easily detected but if left untreated, results in intellectual disability and hyperactivity.
turner syndrome
a missing X chromosome in females can cause intellectual disability and sexual underdevelopment. Just one x. Short, unusual neck shape, cardiovascular problems, higher risk of ostio perosis, perminantly sterile, absense in secondary sex characterics, now they would give you female hormones, sometimes lower iq scores, Verbal ability is in tact. treatment: hormone therapy in childhood and puberty 1/2500 female births
sex linked chromosomal abnormalities
a newborn has an X and Y. Embryos must have at least one X chromosome to be viable. The most common abnormalities are the presence of an extra X or Y or the absense of an X in females. klinefelter fragile x-syndrome turner syndrome XYY syndrome
Genotype
a persons actual genetic material. (fly)
meiosis
a specialized form of cell division that forms eggs and sperm. during this processa cell of the testes or ovaries duplicates its chromosomes but then divides twice, forming four cells, each havingonly half of the genetic material of the parent cell. when the chromosomes re-pair, they do not pair with the same ones, its by chance. before a pair separates, pieces of each chromosome are exchanged, creating a new combination of genes on each chromosome. this process is called crossing over. by the end of the process each egg or sperm has 23 UNPAIRED chromosomes.
Gene-Linked Abnormalities
abnormalities produced by harmful genes. phenylketonuria (PKU) Sickle-Cell Anemia
XYY Syndrome
an extra Y chromosome can cause above average height. no treatment 1/1000 male births
the 23rd pair of chromosomes
are the only pair that are different, and it is the x chromosome for females, and in males the 23rd pair consists of XY. the presence of a Y chromosome is what makes a person male or female.
Down Syndrome
caused by the presence of an extra copy of chromosome 21. 1/900
mitosis
cellular reproduction where the cells nucleus duplicates itself with two new cells being formed, each containing the same DNA as the parent cell, arranged in teh same 23 pairs of chromosomes. the process of dividing the duplicated DNA of a cell, into two new nuclei.
Polygenic Inheritence
characterics are determined by the interaction of many different genes. height reflects the interaction of many genes, as well as the influence of the environment.
non-shared environmental experiences
childs unique experiences, both within the family and outside the family. experiences occurring within the familyl can be part of the non-shared environement
active (niche-picking) genotype-environment
correlations that exist when kids seek out environments they find compatible and stimulating. kids select their environment related to their genotype. outgoing kids seek social events.
passive genotype-environment correlations
correlations that exist when the biological parents, provide a rearing environment for a child. ie. parents who are good at reading and like to read, read well to kids, buy them more books. likely kid will be a skilled reader.
evocative genotype-environment correlations
correlations that exist when the childs genotype elicits certain types of physical and social environments. active, smiling kids get more social stimulation than passive quiet ones.
Monozygotic Twins
develop from a single zygote that splits into two genetically identical replicas, each one a person
Dizygotic Twins
develop from separate eggs and separate sperm, making them genetically no more similar than ordinary siblings.
fertilization
egg and a sperm fuse to create a single cell CALLED ZYGOTE.
epigenetic view
emphasizes that development is a result of bidirectional interchange between heredity and environment. environment can change how genes are expressed.
Evolutionary Psychology
emphasizes the importance of adaptation, reproduction, survival of the fittest, in shaping behaviour
Natural Selection
evolutionary process to continue a species survival. the ability to pass genes to the next generation.
Fragile-X Syndrome
genetic disorder, abnormality in X chromosome. X becomes constricted and often breaks. Most common inherited form of intellectual disability. Can cause learning disabilities, short attention aspan. 1/4000 males 1/6000 females treatment: special education, speech and language therapy
4 Chemicals of DNA
guanine adenine thymine cytosine G A T C
Klinefelter
males have extra X chromosome. XXY undeveloped testes, often enlarged breasts, become tall. deficiencies in verbal intelligence, the degree is related to number of extra X's 1/600 male births treatment: hormone therapy
Dominant Recessive Genes Principle
one gene of a pair always shines through because it is dominant, and overrides the potential influence of the other gene (recessive). when both brown haired parents have the dominant gene for brown hair and recessive gene is blond, they have 1 in 4 chance of having a child with blond hair. you only get the recessive gene trait (blond hair) if you are passed down the recessive gene from both egg and sperm, and there is not a dominant gene passed down.
chorionic villus sampling
prenatal medical procedure 11-13 weeks small sample of the placenta is removed. diagnosis of issues takes 10 days, increases risk of miscarriage by 1%
amniosentesis
prenatal medical procedure 16-20 weeks sample of amniotic (thin sack around embryo) fluid is taken with syringe and tested for chromosomal or metabolic disorders. ultrasound sonography is often used. 1/400 risk of miscarriage
shared environmental experiences
siblings common environmental experiences, such as parents personalities and intellectual orientation, the familys socioeconomic status and the neighborhood.
Zygote
the egg and sperm fuze to form one cell. It is the cell, not the process. in this cell 23 unpaired chromosomes from the egg and 23 from the sperm combine to form one set of 23 pairs. each parent contributes half of the offsprings genetic material. The chromosomes in this cell are not exact copies of those in the ovaries and testes.
Gene X Environment (GxE) Interaction
the interaction of a specific measured variation in the DNA and a specific measured aspect of the environment.
Phenotype
the way a person acts in observable and measurable ways (acts like a fly-buzzes)
chromosomes
threadlike structure, comes in pairs of 23 (1 from ea. parent) contain DNA. every cell has 46 chromosomes arranged in 23 pairs, except the sperm and egg
genes
units of hereditary information composed of DNA. Genes direct cells to reproduce themselves and create proteins that proteins that maintain life. scientists used to think we had 100,000. Now they realize iwe have 20,500. they used to think each gene had just one protein, but we have more proteins than we do genes.
Chromosomal Abnormalities
when a gamete is formed, sometimes the males sperm or females ovum do not have a normal set of 23 chromosomes. examples: down syndrome & abnormalities of the sex chromosomes.
Genetic Imprinting
when the expression of a gene has different effects depending on if the mother or father passed on the gene. A chemical processe silences one member of the gene pair.
