Which of the following best describes an atom? Protons, neutrons, and electrons all grouped together in the center.
A core of negatively and positively charged particles surrounded by neutral particles
A core of positive and neutral particles surrounded by negative particles.
A core of electrons and neutrons surrounded by protons

What factors contribute to the effect an environmental toxin has on the human body?

How do you think earths interior affects what is happening on the surface? 2. how do fossils support the continental drift hypothesis? 3. how does sea- floor spreading support the hypothesis of continental drift? 4.what do scientists observe when they studied the magnetic fields of rocks on the sides of mid-ocean ridges? 5. what is a tectonic plate ? 6. explain mantle convection 7.how can movements of the continents affect earths climate? 8. what occurs during drifting?

How secretion and excretion both are different? explain in simple language.