It’s the first choice because the C at the end does not pair with anything, it was an extra pair that was made
The controlled experiments are performed by the scientists, when they want to study the changes in the sample on changing a single variable. So, the correct answer is option (b).
In case, all variables are kept same, no changes would be observed in the experiment sample. A controlled experiment can be performed on living thing as well as non living. But, controlled experiment cannot be performed on the things which are influenced by a lot of variables, as they cannot create realistic results. So, the option (a), (c), and (d) are incorrect.
D because to help preserve environment everyone has to work together
Answer:
DIFFUSION
Explanation:
Water, carbon dioxide, and oxygen are among the few simple molecules that can cross the cell membrane by diffusion (or a type of diffusion known as osmosis ). Diffusion is one principle method of movement of substances within cells, as well as the method for essential small molecules to cross the cell membrane.
Answer: The following is a <u>postzygotic isolating barrier </u>:
- The hybrid offspring of two species of crocodiles can produce normal gametes but cannot obtain a mate.
Explanation:
<em><u>Reproductive isolation </u></em>occurs when <em>barriers prevent</em> two populations from interbreeding , <u>keeping their gene pools separate.</u>
We can find the Prezygotic isolation that occurs<u> before fertilization </u>can happen.
And the Postzygotic insolation barriers are the reproductive insulation processes that<u> act after the mating</u>. They are all that concern the viability of the individuals produced.
Prezygotic isolation barriers can be temporal, behavioural, geographic , ecological or mechanical; whereas postzygotic isolation barriers include the inviability, infertility or breakdown of hybrid organisms