D. Oxygen
It refers to the pathway by which a chemical element is moved through both the abiotic and biotic compartment of an ecosystem.
A) A flap in the heart located between each atrium and ventricle.
Hope it helps! :)
Answer:
A
Explanation:
This is called the locus and is determined in Meiosis by gametes from parent cells. During meiosis there is this thing called 'crossing over' where the gametes (sperm and egg cells) homologous genes (genes of similar size and shape, such as X and Y chromosomes or X and X) exchange genes on the same locus to provide slightly different characteristics.
Please check this with your teacher but i believe that this is right. Hope this helps. ;)
