Growth and Development: Fetal Development

Determinants of Human Health

  • Primary determinants of a child's physical and mental health:

    • Genetic makeup (heredity)

    • Development in the womb

    • Circumstances of childhood

    • Decisions made by the child's parents

  • Primary determinants of health as an individual ages:

    • As a person grows older, their physical, mental, and spiritual health are affected more and more by the choices made by the individual himself.

Conception and the Zygote

  • Beginning of Human Life:

    • Human life begins when a female reproductive cell, known as an egg cell or ovum [o'vum], unites with a male reproductive cell, known as a sperm.

    • Definition of Conception: The union between an egg cell and a sperm cell is called conception, a term that literally means "beginning."

  • Characteristics and Divine Design of the Zygote:

    • The resulting fertilized egg cell is known as a zygote.

    • Within the zygote, God includes the plans for everything this new life is to become, encompassing traits such as gender, skin coloring, and size of feet.

  • Initial Division as Evidence of Life:

    • Within hours after conception, the single-celled zygote begins to divide, serving as evidence of the life it contains.


Conception and early stages of cell division

Early Cellular Division, Travel, and the Blastocyst Stage

  • Progression of Cell Division:

    • The single cell divides into two cells.

    • The two cells divide into four cells.

    • The four cells divide into eight cells.

    • The eight cells divide into sixteen cells, with cell division continuing sequentially.

  • Journey to the Uterus:

    • As cells divide, the newly formed life travels slowly within the mother's body to the uterus [u'ter-us] or womb.

    • Upon arrival in the uterus, the spherical cluster of cells floats weightlessly for a few days.

  • Structural Differentiation and Blastocyst Formation:

    • As cell division continues, cells begin to develop different characteristics in structure and function.

    • Blastocyst Definition: When the dividing cells form a hollow sphere, the structure is referred to as a blastocyst.

  • Process and Timing of Implantation:

    • Implantation is defined as the process where the blastocyst implants, or attaches, to the lining of the uterus.

    • Timeline: Implantation occurs by the end of the 1st week.

Embryonic Development and Tissue Layer Differentiation

  • Definition of Embryo:

    • Once implantation into the uterine lining occurs, the cluster of cells is known as an embryo.

  • Formation of Three Primary Tissue Layers:

    • As the cells of the embryo continue to divide, they organize into three distinct layers of tissue:

    • First Tissue Layer: Formulated to develop into the baby's blood vessels, muscles, bones, and skin.

    • Second Tissue Layer: Formulated to become the baby's respiratory system and digestive system.

    • Third Tissue Layer: Formulated to become the baby's nervous system.

Sorry, I didn't get that. Can you try again?