Human growth phases
Human growth phases
Prenatal stage three trimesters 9 months from contraception.
Germinal stage. 0 to 2 weeks
of sperm and ovum.
Confined within glycoprotein shell called zona pellucida.
Blastocyst reaches uterus at 5th day. Gets implanted.
Embryonic stage. 3 to 8 weeks
ectoderm endoderm and mesoderm.
Spinal cord and central nervous system and brain develop
4th week eyes nose ears mouth
Rapid growth cell differentiation happens. Various organs created
blood, kidney, nerve cells.
most critical period smoking alcohol
radiation nutrition deficiency be avoided.
5th week arms and legs
8 week basic organs are developed except sex organs
Fetal stage. 9th week.
third month. 12 week.
Second tri mester
fingernails hair ear and eyelashes
increase in size
Brain mature by 28 weeks
muscles 36 fully developed
40 weeks full development
Factors influence. Reilly 2017. Wendell 2013 etc.
•Soci economic, condition. Age of mother. Above 35 potential risk. Behaviour drugs alcohol. Effect of disease like HIV AIDS. Nutrition of mother. Stress in life.
Graph. Length of crown height velocity centimetre/ 4 weeks
Second graph height centimetre start from 16 end with 40.
Neonatal period first month.
Infancy second month till end of lactation 3rd year.
Childhood 3 to 7 years.
Late childhood 7 to 10 for girls and 7 to 12 for boys.
adolescence- 5 to 10 years after puberty.
Most rapid growth during infancy. Deciduous dentition.
like walking and running develop in first two years and cognitive abilities rapidly develop.
acquisition. 1 to 3 years.
Gain 400 gram
every month in first year. Five times birth weight by age of 2.
in 4 years
months rolling. Crawling by 10. Baby steps at 1 year. Climbing stairs by 2 or 3.
Eye coordination at 4 months. Hand mouth coordination 18 months
rapidly growing brain requires rich diet in fat protein energy. Learn behaviour. Butt
digestive system and dentition still weak.
2 kg every year between 3 and 7 thereafter 3kg every year till puberty.
at 6 permanent teeth
brain growth is complete.
First permanent molar appears. Full brain capability allows education and social learning.
Sensory motor and
higher cognitive acquisition during critical periods of plasticity. Hesch 2005
5 centimetre every year height gain
Motor skills. Head lift at 3 months. 8 2 to 5 years for writing skills.