D. The macronucleus does not disintegrate during conjugation.
The macronucleus contains the working copies of genes needed to support an enormous cell. It is formed by a division of the fused diploid nucleus after conjugation followed by multiple rounds of internal gene replication which does not occurs in the micronucleus.
Always report to a teacher or supervisor if anything goes wrong in the lab.
Counter current involves blood in the capillaries flowing in the opposite direction to the flow of water flowing over them. Gases diffuse faster from one area to another when the concentration difference between the two areas is at its greatest, as compared to when the concentration difference is low.
All organisms do have a closed circulatory system
so A <span />
iconic bond -> sharing of many electrons
metallic bond -> sharing of electrons
covalent -> transferring of electrons
hope this helps...
