Basic Principles of Development Factors of Growth & Development Pre-Natal development 1-9 months of development Intrauterine Nutrition 6 Mechanisms of Transplacental transfer Adaptive Mechanism of oxygenation Uterine Accomodation Organ development Sensory development Nervous system Circulatory system Respiratory system Blood Immunity Lymphatic system Digestive system Urinary system Skeletal system Muscular system Cutaneous structure
Temperament: A child’s characteristic behavioral response to internal and external stimuli 1. Easy, highly adaptable child 2. Difficult child 3. Slow-to-warm-up Psychological: Child-rearing environment, family functioning, attachment and contingency Attachment: Tendency of a young child to want to be near the parent during times of stress Contingent responsiveness: Reinforcement depending on the behavior of the other Social: Socio-economic status, family system, extended family, subculture, culture and society
Specific Objectives To define & differentiate growth & development To discuss the principles of development and its effects on the child To discuss the factors affecting growth and development To discuss prenatal and organ development Growth An increase in size & mass Quantitative Development An increase in function/skills Qualitative More complex & broader May or may not be interchangeable but actually inseparable from growth Basic Principles of Development 1. Development proceeds in an orderly and predictable sequence -- cephalocaudal direction and proximodistal 2. Development proceeds from general to specific, from the basic to the more specialized 3. Development depends on maturation and learning, on the combination of both genetics (nature) and environment (nurture) 4. Early development is more critical than later development 5. There are developmental domains, within which are developmental lines leading up to developmental tasks for the individual 6. Development is progressive and dynamic 7. The rate of development is unique to each individual 8. Development is interactional
Factors of Growth & Development Biological: Genetics, prenatal factors, postnatal illnesses, nutrition, environment, physical & neurological maturation
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“ it is easier for a camel to pass through the ye of a needle if it is lightly greased.” – Kehlog Albran
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Trophoblasts, outer layer of blastocyst, precursor cells of placenta – first appear 4 days after fertilization Placental supply starts – 3 weeks after fertilization or 1 week after implantation Primitive umbilical ring – end of 5th week after fertilization Placental permeability increases - latter part of pregnancy
A 7.5-day human blastocyst, partially embedded in the endometrial stroma. The trophoblast consists of an inner layer of mononuclear cytotrophoblast and an outer layer without distinct cell boundaries, the multinucleated syncytiotrophoblast. The embryoblast is formed by the ectoderm and endoderm. The amniotic cavity appears as a small cleft.
Six Mechanisms of Transplacental Transfer 1. Osmosis: Electrolytes transfer by simple diffusion 2. Facilitated Diffusion: Substances transfer through carrier system or complexes 3. Active Enzymatic Transfer: Molecules transferred against electro-chemical gradient 4. Destruction: Compounds altered sufficiently destroying their physiological activity 5. Pinocytosis: Whole molecules are engulfed by macrophages 6. Membrane Leakage: Intact cells like red cells transfer from fetus to mother and vice-versa Adaptive Mechanisms for Oxygenation 1. Many times increase in the cardiac output 2. Favorable oxygen dissociation in the fetus 3. Increased oxygen capacity 4. High red blood cell count 5. Capacity to reset to anaerobic metabolism
By the 2nd week
The embryoblast contains both the ectodermal and...