Mendelism 
the case of what he called alternating characters, 
that only one or other of the pair can appear in 
the offspring, that they will not blend. If both 
parents display one of the opposing characters, 
the offspring will of course show it. But if one 
parent display one character and the other the 
opposing character, the hybrid offspring will dis- 
play one only, and that which is dominant. The 
other character is suppressed for the time being. 
When, however, these hybrids are bred zuter se, 
their gametes or sexual cells split up into their 
component parts, and then the recessives are free 
to unite with other recessives and thus produce 
offspring which show the recessive character. 
His results can be set forth in symbols. 
Let T stand for the tall form and D for the 
dwarf form. Since the offspring are composed 
of both the paternal and maternal gamete, we 
may represent them as TD. But dwarfness is, 
as we have seen, recessive, so that the offspring 
all look as though they were pure T’s. When, 
‘however, we come to breed these TD's zxtfer se, 
the gamete or sex-cell of each individual crossed 
breaks up into its component parts T and D, 
which unite with other free T or D units 
to form TD’s or TT’s or DD’s. What are 
the possible combinations? A D of one parent 
may meet and unite with a D of the other 
parent, so that the resulting cells will be pure 
D, ze. DD, and will give rise to pure dwarf 
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