Me 3.2a Physical Development Across the Lifespan: Prenatal Development, Infancy, and Childhood Flashcards
Conception
One of several million sperm cells penetrate a mature egg creating a fertilised egg or zygote.
zygote
Fertilised egg in a woman
how many zygotes survive past 2 weeks?
No more than half.
germinal stage
the stage where the zygote begins to divide in order to implant into the uterine wall. Once implantation is complete, the embryonic stage begins.
First week after concpetion
Cell division produces some 100 IDENTICAL cells.
After first week of conception
Cells begin to differentiate - specialise in structure and function.
placenta
An organ that forms in the womb, also called the uterus, during pregnancy. It is the life-link that transfers nutrients and oxygen from mother to embryo. Outer cells become this.
Embryo
The inner cells of the zygote turns into this: the baby.
next 6 weeks
Over the next 6 weeks, the embryo’s organs begin to form and function.
fetus
From around nine weeks after conception until birth, the developing human organism. Unmistakably human.
threshold of viability
the baby has developed enough and is likely to survive if born prematurely.
Since when can fetuses hear sound
6 months after conception
Why do babies prefer mother’s voice and language over others?
They hear that in the womb.
When can fetuses learn?
2 months before being born.
Teratogens
agents, such as chemicals and viruses, that can reach the embryo or fetus during prenatal development and cause harm.
