Watch this video about the stresses on the body caused by carrying heavy backpacks. then design an investigation about the effect of carrying backpacks on students’ health using these steps of the scientific method: make observations or inferences ask questions construct hypotheses and make predictions test hypotheses analyze results your investigation can address any question you have about backpacks and student’s health that you choose.

How many cells are our body made of ? ♡

Afamily has a y-linked disease that affects the father. what is the chance of a male offspring inheriting the same disease? oa. 100% ob. 50% oc. 25% d. 0%

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.