When a cell is in G2 phase, it has already doubled in S phase its DNA, meaning that for each chromosome we have two chromatids -> 2n(number of chromosomes)×2(number of chromatids per chromosome)=number of chromatids. If 160 is the number of chromatids on G2 phase of a chicken cell, it means that the cell has 80 chromosomes (2n), and after meiosis, process to form a sperm cell, will only have 40 chromosomes (n).
The correct answer among the choices provided is option A. Lung capillaries are responsible for exchanging carbon dioxide for oxygen from the air. Blood that comes from the heart gets oxygen from the alveoli. The carbon dioxide in the blood goes into the alveoli at the same time.
Plants and trees couldn't thrive without capillary action. Capillary action helps bring water up into the roots. With the help of adhesion and cohesion, water can work it's way all the way up to the branches and leaves.