Explain how a trait might seem to “disappear” for a generation, and then “reappear” in the following generation.

If all of the individual in a generation receives one dominant allele and one recessive allele, then they will all show the dominant trait.

If they are bred, they will pass on the dominant allele to some of their offspring and recessive allele to others.

If an offspring receives two recessive alleles, it will show the recessive trait and therefore it will reappear.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.

sorry, is there a picture? i do not see any arrows.

wut? unius0123 wut?