<span>More than 50</span>. There are more than 7000 chemicals in cigarette smoke, 250 of which are known to be detrimental to health and 69 chemicals are carcinogenic (can cause cancer). Some of the carcinogenic chemicals in cigarette smoke are: Arsenic, Cadmium, Chromium, Formaldehyde and Nickel.
I think this is correct
1. Organelle, cells, tissues, organs, organ systems, organisms, population, communities, ecosystems and finally biosphere.
2. (Human Body) Bone cells, Fat cells, Nerve cells.
3. neuron, a collection of neurons, nervous system, brain
4. Plants don't have a liver, stomach or lungs, while animal organ systems do.
No, because it says "does not budge" which means it doesnt move at all.
Q: On steep slopes and mountains,____ helps reduce erosion by creating level areas for crops.
A: terracing
The correct answer is mutualism. The bird feeds off the insects and parasites on the alligator, and the alligator doesn't have to worry about those insects and parasites hurting him anymore.
