4.3a Multicellular organisms exhibit complex changes in development, which begin

after fertilization. The fertilized egg undergoes numerous cellular divisions that will

result in a multicellular organism, with each cell having identical genetic information.

4.3b In humans, the fertilized egg grows into tissue which develops into organs and

organ systems before birth.

4.3c Various body structures and functions change as an organism goes through its life

cycle.

4.3d Patterns of development vary among animals. In some species the young resemble

the adult, while in others they do not. Some insects and amphibians undergo metamor-

phosis as they mature.

4.3e Patterns of development vary among plants. In seed-bearing plants, seeds contain

stored food for early development. Their later development into adulthood is character-

ized by varying patterns of growth from species to species.

4.3f As an individual organism ages, various body structures and functions change.