http://www.ck12.org Chapter 1. Human Biology
FIGURE 1.137
This baby is six months old, and his baby teeth have started to come in.
Babies often chew on toys or other objects when they are getting new
teeth. They may even chew on their toes.also develop quickly during this stage. By age three, most children can run and climb steps. They can hold crayons
and scribble with them. They can also feed themselves and use the toilet.
From age three until the teens, growth is slower. The body also changes shape. The arms and legs get longer
compared to the trunk. Children continue to develop new motor skills. For example, many young children learn
how to ride a tricycle and then a bicycle. Most also learn how to play games and sports (Figure1.138). By age six,
children start losing their baby teeth. Their permanent teeth begin coming in to replace them. They also start school
and learn how to read and write. They develop friendships and become less dependent on their parents.
FIGURE 1.138
Children develop better motor skills as they get older.Vocabulary
- childhood: Phase of life that begins after the first year and continues until the teen years.
- infancy: First year of life after birth in humans.
- toddler: Child aged one to three years.