HD 1004 Lecture Notes - Lecture 3: Acupuncture, Music Therapy, Cerebral Palsy
Document Summary
Support for the embryo. (3) implantation takes place about 10 days after conception with the attachment of the zygote to the uterine wall: the second stage of prenatal development is the embryonic period and it lasts from about. The developing organism is now called the embryo: during this phase, cell differentiation intensifies and some cells form support systems while others develop into organs. These include the following: (1) the amnion is a fluid-filled bag in which the embryo floats. (2) umbilical cord: the umbilical cord contains two arteries and one vein that connect the embryo to the placenta. Small-molecule materials, such as oxygen, water, salt, carbon dioxide, and nutrients can cross back and forth between mother and infant. The fetus shows a preference for a certain position in womb: by the end of the 6th month, eyes and lids have formed, fine hair covers the head, and the grasp reflex is present.
