Why were there only female tortoiseshell kittens ?

Ibelieve that it's : all tortoiseshell  and  tortoiseshell  and white (calico)  cats  are  female. but not  all  gingers are male, though most are. the reason is that in  cats  the colour gene is carried on the x chromosome. this could happen if the father was ginger and the mother  tortoiseshell.

Circulatory and respiratory.

This diagram has to do with the exchange of oxygen  and carbon dioxide, meaning it represents the circulatory system. Additionally, it also features blood cells, representing the respiratory system.

Let me know if this helps!