Answer:
From fertilization and to the end of the second week.
Explanation:
The development of the fetus is divided into three periods, established by most embryologists: pre-embyonic period, which goes from fertilization to the second week of development, embryonic period, which goes from the third week to the eighth week, and the fetal period, which goes from from the third month until the end of pregnancy.
The pre-embyonic stage begins at fertilization and remains until gastrulation. By the end of the second week the embryo already has the neural tube formed, although it is still open at both ends.
A 67-year-old male presents with weakness, dizziness, and melena that began approximately 2 days ago. He denies a history of trauma. His blood pressure is 90/50 mm Hg and his pulse is 120 beats/min and thready. You should be most suspicious that this patient is experiencing:
gastrointestinal bleeding.
Terms such as behavioral interdependence, need fulfillment, and emotional availability describe which type of relationship?
a. behavioral
The primary visual cortex is what sends information to the secondary visuals, which are important for color, motion, and depth perception. If the primary visual is damaged, then it can cause problems for the secondary visuals, which are important for the three reasons listed ^.
You use it by first making a observation, second ask questions, third do background research, and fourth form a hypothesis