Answer:
trophic level
Explanation:
Each step of the food chain in the energy pyramid is called a trophic level.
Earth's orbit is the path in which the Earth travels around the Sun. The average distance between the Earth and the Sun is 149.60 million kilometers (92.96 million miles) and a complete orbit occurs every 365.256 days (1 sidereal year), during which time Earth travels 940 million kilometers (584 million miles
The initial stages of human embryogenesis.
8-cell embryo, at 3 days.
Blastocyst with an inner cell mass and trophoblast.
Trophoblast differentiation.
Histogenesis of the three germ layers.
Artificially colored - gestational sac, yolk sac and embryo (measuring 3 mm at 5 weeks)
Embryo attached to placenta in amniotic cavity.
