Science Practice Questions

A myocardial infarction (heart attack) results from a blockage in which of the following blood vessels of the heart?

Which of the following skin layers contains stem cells that produce new cells which migrate to the skin surface over time?

In the following balanced chemical equation, how many oxygen atoms are present on each side of the reaction? 2 C2H6 + 25 O2 → 16 CO2 + 18 H2O

How many electrons are found in a neutral boron atom with an atomic number of 5 and a mass number of 11?

A researcher is comparing the surface areas of the following cells under a microscope: a red blood cell, a neuron, a muscle cell, and a bacterial cell. Which of these cells is likely to have the smallest surface area?

A patient goes to the doctor with a cold and sore throat and asks for antibiotics. The doctor refuses to prescribe antibiotics because the illness is caused by which of the following pathogens?

Under a microscope, which of the following is most likely to be seen if the microbe being examined is a fungus?

A researcher wants to gather data on the average wing strength of all birds found in the American Northwest. The researcher only had one small net, so all large birds were excluded from the study. The researcher's results were different than expected, but he believes his data include enough birds to estimate the wing strength of all birds. For which of the following reasons should this data be rejected?

Which of the following enzymes begins the digestion of polysaccharides into simpler sugars?