I think the correct answer from the choices listed above is option A. Sickle cell disease is caused by a change in allele. It is a disorder of the blood caused by an inherited abnormal hemoglobin. Hope this answers the question. Have a nice day.
It's B
Explanation:
Because the fossil record shows how organisms have evoluate from relatively simple organisms to more complex organisms
A terrestrial ecosystem is a land-based community of organisms.
Answer:
highlighted in bold above, are a struggle for existence, variation and inheritance
Explanation:
i hope this helps
Speciation is the adaptive divergence and gradual that leads to two different species.
Reproductive isolation results in speciation when the processes of evolutionary mechanisms, physiological and behaviours are collected.
Mechanism of reproductive isolation helps in preventing members of different species from producing offsprings. A zoologist is a classified way of reproductive isolation whereby it(zoologist) is classified to the mechanism of reproductive isolation into two categories
(i) Pre-zygotic. This one acts before fertilization or before mating when it comes to animals.
(ii) Post-zygotic. It acts after fertilization.
The mechanisms appear I species which are genetically controlled and whose geographic distribution overlaps or are separated.
