An atom of calcium contains 20 protons. how many electrons does it have?

What is the difference between the conducting zone and the respiratory zone of the respiratory system? the conducting zone is a series of cavities and tubes that move air to the respiratory zone where gases exchange with the bloodstream. the conducting zone exchanges gases between the lungs and the alveoli and the respiratory zone is a series of cavities and tubes that move air to the conducting zone. the conducting zone moves oxygen into the cells and the respiratory zone takes carbon dioxide away from the cells. the conducting zone moves oxygen into the bloodstream and the respiratory zone takes carbon dioxide away from the bloodstream.

Genetic disorders can result when sister chromatids fail to seperate properly. during what phase is this problem most likely to occur?

What happens when a plant is losing too much water through transpiration? question 14 options: stomata open stomata close guard cells swell respiration increases