8 Unit 1 Children and Families in Today’s World Copyright Goodheart-Willcox Co., Inc. that involve children. These stages are described in Figure 1.2. Factors That Infl uence Growth and Development Why is each child different? Two main factors infl uence growth and development. First, each child has unique, inborn traits. Heredity includes all the traits that are passed to a child from blood relatives. Sometimes heredity is called nature. Second, a child’s surroundings also play a large role. Environment includes all the conditions and situations that surround and affect a child. Some- times environment is called nurture. The way these two factors combine also makes children different from one another. Experts are studying how these two factors affect children’s growth and development. They continue to learn, but unanswered questions remain. Heredity You have many traits in common with all the other members of your family. These traits pass to you in complex ways through your parents’ genes at the moment of conception. Babies inherit about 23,000 genes from their parents. Genes are sections of the DNA molecule found in a person’s cells that determine his or her individual traits. Genes carry the inborn instructions that help make you who you are. A person’s genes are called the structural genome (JEE-nohm). Like computer hardware, this genome determines the boundaries of what is possible. Child development researchers have long been interested in the effects of heredity. They noted Figure 1.1 Child Development Domains • How children’s bodies grow and mature. • How children’s large and small muscles develop and aid movement. • How children’s motor skills aid perception and vice versa (called perceptual- motor development). • How children learn. • What children learn. • How language skills develop. • How children develop and sustain relationships with others. • How children develop a sense of self. • How children become dependable. • How children develop morals and character. • How children identify and understand their feelings. • How accurately children can read the emotional states of others. • How children manage strong emotions and express their feelings in constructive ways (called self-regulation). Emotional development Intellectual development Physical growth and development Social development