A Closer Look at Conception Chapter 5 Section 2

The Genetic Package Chromosomes- tiny threadlike particles in the nucleus of every cell. Come in 23 pairs (babies receive 46) Genes- units that determine the child’s inherited characteristics. (genes make up chromosomes as beads make up a necklace)

Dominant and Recessive Genes Dominant genes- stronger genes (Brown hair or brown eyes) Recessive genes- weaker gene (Blonde hair or blue eyes)

Multiple Births When cells continue to divide and grow into separate embryos! Identical Twins Fraternal Twins About 2.5% births are twin births in the United States (fraternal twins occur three times more often) Babies are more likely to be premature Mother is more likely to experience excessive bleeding

Infertility Infertility- the inability to become pregnant Surgery or medication may solve the problem Fertility drugs- help stimulate a woman’s ovaries to release eggs Fertility drugs may cause serious side effects (lung problems, abdominal pain, diarrhea etc..) and increase the chances of multiple birth

Options for Infertile Couples 1. Adoption 2. Artificial Insemination a doctor injects sperm into a woman’s uterus with a special needle. It can come from the husband or a donor

Options for Infertile Couples In vitro fertilization- this process is used when a woman has damaged fallopian tubes that prevent pregnancy. In a small glass dish the doctor combines a mature egg from the woman and sperm from her husband. If fertilization takes place the doctor places the zygote in the woman’s uterus

Options for Infertile Couples Ovum transfer- procedure uses an egg taken from a female donor and in vitro fertilization. It may be used by women who lack working ovaries or who have inherited disorders Surrogate mother- mother is a woman who becomes pregnant for another couple. She may carry a couples fertilized egg.

Do you think these practices raise many ethical questions?