Examlex
If the rotational speed of the gas in the disk of a spiral galaxy is 200 km/s at a distance of 80,000 light-years from its center,then what is the mass enclosed within this radius?
Embryonic Period
The period from 2 to 8 weeks after fertilization, during which the major organs and structures of the organism develop.
Zygote
Cell resulting from the uniting of the ovum and sperm.
Umbilical Cord
The flexible cordlike structure connecting a fetus to the placenta, delivering nutrients and oxygen and removing waste.
Psychological Closeness
The perception of being emotionally intimate or connected with another person or group.
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