Cardiac muscle cells have a higher concentration of mitochondria than
skeletal muscle cells. what does the difference in mitochondrial
concentration most likely indicate about cardiac muscle cells compared
with skeletal muscle cells? (why do they have more mitochondria? )

cardiac muscle require lot of energy to perform while skeletal muscle are used in coordinate of bone moments so they require less energy since mitochondria is powerhouse cell so it is highly concentrated in cardiac muscle...

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.

hi~~

i would say that hybridization occurs frequently in nature, because there are many types of hybrids that have occurred naturally, such as the mule (male donkey + female horse)