Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Carl P. Gabbard PowerPoint ® Lecture Slide Presentation revised by Alberto Cordova, University of Texas at San Antonio Chapter 5 Factors Affecting Growth and Development

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Chapter Overview Prenatal Maternal (internal) factors External (environmental) factors Postnatal Nutrition Physical activity Hormones (review of chapter 3)

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Prenatal Development Protected by the placenta, but not impervious to the outside environment Teratogen Environmental agent that can cause birth defects or kill the fetus Sensitive Period (Susceptible to insult) Embryonic period (2 to 8 weeks or 1st trimester)

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Teratogenic Effects Interfere with basic biochemical processes Susceptibility varies with developmental stage Act in a specific way Affect organisms differently Concentration and exposure are related to risk May not affect the mother May cause temporary delayed affects or long-term consequences

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Internal (Maternal) Factors Maternal age Nutrition Genetic abnormalities Down syndrome Phenylketonuria (PKU) Maternal Stress

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings External (environmental) Factors Infection and Disease STIs HIV/AIDS Drugs and chemical substances Smoking Alcohol Drugs Low birth weight Catch-up growth

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Low Birth Weight Chief contributor to infant illness and mortality Weight less than 5.5 lbs (2,500 g) VLBW less than 3.3 lbs (1,500 g) Causes deficits in physical growth and motor behaviors Primary causes include: nutrition, smoking, alcohol, drugs, etc. Figure 5.1

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Premature (born preterm) Born prior to 38 weeks after conception 38 to 42 weeks is normal Immature Respiratory Temperature-control Immune Low Birth Weight

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Postnatal Development Nutrition and Physical Activity 65% of adults are overweight. 50% of young people are not physically active. Poor diet and physical activity cause around 300,000 deaths per year. Type 2 diabetes is on the rise. Low physical activity levels have become characteristic of children, leading to more overweight children.

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Malnutrition: Inadequate intake of energy because of a lack of sufficient calories or quality protein Underweight: BMI of 18.5 or 5th percentile on growth charts Undernutrition Figure 5.2

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Overnutrition is consuming too much or the wrong kinds of food. Common outcomes are conditions of overweight and obesity. Heredity versus environment Overweight: BMI 25 to 29.0 Obesity: BMI > 30 or above 95th percentile on growth charts Overnutrition

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Breastfeeding The federal government and major health organizations support the claim that breastfeeding has medical benefits. Benefits include: Lower risk for ear and respiratory infections Lower risk for gastroenteritis Lower risk for type 2 diabetes Lower risk for sudden infant death syndrome (SIDSs) There are also several benefits to the mother.

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Physical Activity Stature Body mass Lean / fat Fat cell theory Body proportion and physique

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Physical Activity Figure 5.3 Skeletal growth and development Mineralization / density Sexual maturation Menarche Muscular development and strength Neural (motor) recruitment Cardiorespiratory development Skill-related fitness

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Glands and Hormonal Activity Pituitary (GH) Thyroid (throxine) Pancreas (insulin) Adrenal Gonads Ovaries and testes

Copyright © 2012 Pearson Education, Inc., publishing as Benjamin Cummings Summary A number of maternal and external factors can have a profound effect on the development of the unborn infant. Exposure to harmful agents (teratogens) can cause negative reactions in the form of birth defects and behavioral dysfunctions. In general, habitual physical activity is shown to have positive effects on the body. One of the most influential factors in physical growth and development throughout the lifespan is hormonal activity.