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Growth & Development

  Heredity & Environment
- Genetic Code -

Growth & Development

Ψ  The Beginnings of life

•  The name for a human reproductive cell is gamete, they are either sperm or ovum.
 •  When a sperm & ovum fuse a living cell called a zygote is formed.

Ψ  The genetic code

•  The genetic code is a sequence of chemical compounds (called bases) that is held within DNA molecules & directs development, behavior & form.
•  The basic unit of genetic instruction is the gene, which is a discrete segment of a chromosome (gene carrier).
•  Genes can have several variations (alleles).
•  A karyotype portrays a person's 46 chromosomes (23 pairs).
•  Sex is determined by the 23rd chromosome pair; XY is male, XX is female.

•  The human genome is like a blueprint for creating humans. Your genome contains all the genetic (gene) information needed to create you, & to determine how your cells function throughout your whole life. Every one of your body cells, contains a copy of your genome. The human genome contains about 25,000 genes.

It's a Mickey Mouse World , isn't it?

Growth & Development
Robert C. Gates