Males have two dissimilar chromosomes X and Y/heterogametic;
Females have two similar chromosomes X and X/homogametic;
Male gamete/sperms have either X or Y chromosome, while all ova have X chromosome;
If a sperm with X fuses with an ovum a female is formed and if a sperm with Y fuses with an ovum a make is formed;
Sickle-cell trait is heterozygous while sickle cell anaemia is a homozygous condition;
People with sickle cell trait are resistant to malaria; because the plasmodium cannot survive in sickle shaped cells.
adhixbelly answered the question on September 20, 2017 at 09:40
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