Not always.
Two eggs are released and both get fertilised.
Identical and Fraternal There are identical and fraternal. Fraternal twins happen when 2 different embryos start growing at the same time, so you get a brother and a sister or 2 sisters or 2 brothers that are the same age. Identical twins happen when 1 embryo splits into 2 embryos when it is only a few cells big, so both babies have the same genes.
Yes babies can be called twins. Also when they grow up they"ll still be called twins.
A set of twins (2 babies) is called twins. Seven sets would still be twins. 7 babies born together (not twins) would be called septuplets.
Conjoined twins. The older terminology was Siamese twins, after the first recorded twins in the country of Siam (now called Thailand).
siblings
Cleopatra's twins were called Alexander Helios and Cleopatra Selene.
A set of seven twins is called septuplets.
Neptune and uranus are called twins. The Earth and Venus are called twins because of the similarity in size. See the related link for more information. The Earth and mars are not considered twins.
The cell disappears...
the twins were thomson and thopson.