The lymph is moved through the body in its own vessels making a one-way journey from the interstitial spaces to the subclavian veins at the base of the neck. Since the lymphatic system does not have a heart to pump it, its upward movement depends on the motions of the muscle and joint pumps.
The only independent variable in this experiment is the amount of nitrogen Sarah uses. All of the other variables are dependent on other factor and processes, but Sarah controls the amount of nitrogen that she uses for each plant.
Cyanobacteria are primitive organisms where chloroplasts are believed to be originated. Now, with the theory of endosymbiosis, this suggests that these organelle from cyanobacteria was engulfed by other organisms which has helped them process light with the help of chloroplasts.
Neanderthals have contributed approximately 1-4% of the genomes of non-African modern humans, although a modern human who lived about 40,000 years ago has been found to have between 6-9% Neanderthal DNA