Chp 8 The developmental perspective

Human development

Is the scientific study of changes that occur in people as they age from conception until death

longitudinal design

is a research design in which one participant or group of participants is studied over a long period of time the participants are measured repeatedly over time to show related changes

Cohort effect

is a Impact on development when a group of people share common time period or life experience 

Cross- sectional design 

is a research design in which several different age groups of participants are studied at one particular point in time

Cross -sequential design

is a research design in which participants are first studied by means of a cross sectional design and then the researcher then follows all these groups and retest them at multiple points in the time hybrid design

Nature

the influence of our inherited characteristics on our personality , physical growth , intellectual growth and social interactions

Nurture 

is the influence of the environment on personality , physical growth  , social interactions  and intellectual growth 

Genetics

is the science of inherited traits

Dna

is a special molecule that contains the genetic material of the organism

the chemical makeup of Dna is 

Adenine, thymine, guanine and cytosine 

you read a Dna from

5 to 3

Gene

is a section of DNA having a certain pattern of chemical elements

Chromosome 

is a tightly wound  strand of genetic material or dna 

Humans

have 46 chromosomes in each non reproductive cell in our body’s 23 from the mother and 23 from the father

conception

The union of the sperm and the ovum

Ovum 

the female  sex cell or egg

Zygote

is a cell resulting from the uniting of the ovum and sperm that divides into many cells eventually forming the body

Monozygotic twins : identical twins

Is formed when one Zygote splits into two separate masses of cells , each of which develops a separate embryo

Dizygotic twins 

is also called fraternal twins  occur  when two eggs get fertilized by two different sperm , resulting in the development of two zygotes in the uterus at the same time  

The three stages of development

1 Germinal period , embryonic period , Fetal period and Critical periods

Germinal period

is the first two weeks after fertilization during which the zygote moves down to the uterus and begins to implant in the lining

Embryonic period 

is the period from two to eight  weeks after fertilization  during which  major organs and structures of the organism develop or major organogenesis occurs 

Embryo 

is the name for the developing organism from  two weeks  to  eight weeks  after fertilization 

Fetal period

the time from about eight weeks after conception until the birth of the child

Fetus

is the name for the developing organism from eight weeks after fertilization to the birth of the baby

Viability 

is the point  at which it is possible for an infant to survive outside the womb usually about 22-26 weeks 

Critical periods

is the times during which certain environmental influences can have an impact on the development of the infant 3-12 weeks after fertilization

Teratogen

is any factor that can cause a birth defect

Thalidomide 

is a factor that can cause  a  birth defect  because its made to  regulate the immune system but is used for  morning sickness for mothers . as a result it can cause congenital defects 

Reflexes that infants are born with

Grasping , moro (startle), rooting ,stepping ,sucking

Startle reflex

is also know as the the moro reflex when you touch a baby,s cheek it will turn toward your hand and open its mouth in search for the mothers breast

stepping reflex and sucking reflex

are infant reflexes that can be used to check the health of an infants nervous system . if a reflex is absent or abnormal it may indicate brain damage or some other neurological problem

Motor development

is tremendous motor development from birth to age 2

Infant’s brains consists of 

86 billion neurons 

synaptic pruning

is unused synaptic connections and nerve cells cleared away to make way for functioning connections and cells

Adults have

7-8000 synapse per neurons

babies at birth have 

2,500 synapse per neuron 

Senses

Expect for vision senses are fairly well developed at birth .at birth babies prefer black and white contrast at a very short distance

babies color vision comes

at 4 months old

the six motor milestones are

raising head , rolling over , sitting up with support , sitting up without support , crawling and walking 

Raising head and chest

happens around 2- 4 months in a babies life

Rolling over

this stage happens 2- 5 months in a babies life

sitting up with support 

this stage  happens around 4-6 months old in a babies 

sitting up without support

this stage happens around 6-7 months in a babies life

Crawling

this stage happens around 7-8 months in a babies life

walking 

this stage happens around 8-18 months in a babies life 

cognitive development

is the development of thinking , problem solving and memory

Jean Piaget

developed a four stage theory of cognitive development based on observation of infants and children