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.
<span>The twisted ladder shape of DNA is called a double </span>helix.
<span>There are many indicators for predator presence. Some of them are:
Being able to spot predator marks like scratches or fur.
Being able to feel predator movements.
</span><span>Echo-location </span>For example, moths respond to the echo-location calls from their bat predators; moths drop to the ground once they hear the sound pulse from the bat.
<span>Blowflies burrow into the ground at the completion or, 4th instar stage (17 mm size,) of their larval growth. After burrowing into the ground, the larvae transform into the pupal stage. They remain underground in the pupal stage for 6 to 8 days at which time the adult fly emerges.</span>
Personally, I think since all the changes in the world are affecting the natural environment adaptive traits are important so that they can help maximize its reproductive success so its species can survive.