principles of growth Flashcards
what 4 periods can growth be divided into
intrauterine, infancy, childhood, adolescence.
nonpathological factors affecting growth
genetics, age, sex, nutrition, socioeconomic status, environmental influences.
what is meant by intrauterine environment
placental function (the nutrient supply!), maternal size and length of gestation.
what determines size at birth
Genetics and the intrauterine environment
after the first year of life what is the major determinant of of growth
life environment and nutrition
later on in childhood what is the major determinant of of growth
thyroid and growth hormone will largely determine growth and problems here if there are any will be picked up
At puberty and into adulthood what is the major determinant of of growth
the sex steroids will shape secondary sexual characteristics and further growth.
actions of Growth Hormone
ncreasing lipolysis, protein synthesis and gluconeogenesis it stimulates release of IGF-1 from the liver
effect of IGF-1
its effects on chondrocytes and growth plate of bones.
endocrine drivers at fetal/infant
Insulin and IGF2
endocrine drivers at child
Growth hormone and IGF1
endocrine drivers at adolescent
Growth hormone and sex steroids
gestational week 10-12 what happens
- tooth buds appear, these will form the baby teeth
- limbs are long and thin
- foetus can make a fist with its fingers
- genitals appear well differentiated by this point
- Erythrocytes start to be produced in the liver and heartbeat can be detected by ultrasound
gestational week 13-16 what happens
At week 15, the main development of external genitalia is complete
gestational week 22 what happens
- The foetus reaches a length of 28cm and weighs about 500g
- The eyebrows and eyelashes are well formed and all of the eye components are developed
- The foetus now has the startle reflex
- Footprints and fingerprints continue to form
- Alveoli forming in the lungs