Answer:
3
Explanation:
Male ; EeHh
Female ; EeHh
Then,
possible gametes for each = EH / Eh / eH / eh
where,
EH Eh eH eh
EH EEHH EEHh EeHH EeHh
<em> One eye One eye One eye One eye</em>
<em> One horn One horn One horn One horn</em>
<em />
Eh EEHh EEhh EeHh Eehh
<em>One eye </em><em>One eye</em><em> One eye </em><em>One eye</em><em> </em>
<em>One horn </em><em>Two horn</em><em> One horn </em><em>Two horn</em>
eH EeHH EeHh eeHH eeHh
<em>One eye One eye </em><u><em>Two eye</em></u><em> </em><u><em>Two eye </em></u>
<em>One horn One horn </em><u><em>One horn</em></u><em> </em><u><em>One horn</em></u><em> </em>
eh EeHh Eehh eeHh eehh
<em>One eye </em><em> One eye </em><em> </em><u><em>Two eye</em></u><em> </em><u><em> Two eye </em></u>
<em> One horn </em><em>Two horn </em><em> </em><u><em>One horn</em></u><em> </em><u><em>Two horn </em></u>
<u><em /></u>
Therefore,
One eye, one horn:One eye, two horn:<u>Two eye, one horn</u>:Two eye,two horn
is,
9 : 3 : <em><u>3 </u></em>: 1
This ration proves that the above working is correct and is dihybrid cross.
The right answer is <span>Refractory period.
At the moment when the action potential is emitted, the fiber being depolarized, it is impossible to depolarize it again. It is, therefore, necessary to wait until the membrane potential returns to a value below the critical threshold in order to be able to excite it again. We are thus led to distinguish two periods that characterize its excitability.
An absolute refractory period: during which any stimulation, even supraliminal, is ineffective since the fiber is already depolarized.
A relative refractory period: during which a second action potential can be omitted provided that the depolarization produced by the excitation reaches the critical threshold, which implies that it is more important since the value of the resting potential has not been restored yet.</span>
450 mya, is where you would find fossils.
Explanation:
The first layer would be newer organismis that haven't quite decayed yet.The second and third layer is where the bones of the dead organasims lie, they havent quite been through the whole process yet, but they are nearly complete just about 100,000 years left.The fourth layers have been through alot, and have been there for many many years we can say abot 100,000,000 years.They are ready to become a fossil fuel.