The answer is adenine.
The nitrogenous base pairings are always adenine with thymine and cytosine with guanine.
I remember this as
· the two round letters (C and G) pair together
· the two straight-edged letters (A and T) pair together
Hopefully that helps.
Answer: Lungs
Explanation: The pleura encloses each lung by a double layered serous membrane
The correct answer should be A. spores
Ferns don't have seeds and they reproduce using spores. Cones have seeds in them and seeds fall out. Pollen enters a flower and then the flower becomes a fruit. This is sexual reproduction of plants. Since ferns don't have this, they have to reproduce with spores.
