The answer is D. Most cells have a membrane but some dont
I would try to eat more healthily because eating certain foods are a huge magnet to toxic waste and gas. This creates more pollutions and destroys the o-zone. Another thing it to take my bike instead of car or use a hybrid or an electric car if it is to far ( my destination) for a bike. Cooking food in my house with an oven is MUCH better for the clean air as well for the coal and charcoal used for grill, and wood for fires, causes a massive pinpointed area of smoke and destroy the air causing bug leaks of hydrogen in the air molecules.
<span>Carbon has four valance electrons.
Carbon forms the backbone of all organic molecules.
Carbon can form bonds with four different atoms.
Carbon can from four covalent bonds with another carbon atom.</span>
<span>Carbon is the answer you are looking for. However, not all carbon containing molecules are organic. Examples being carbon oxides such as CO (carbon monoxide) and CO2 (carbon dioxide). Some Chemists classify organic compounds as having a C-H bond present but this is not completely correct as this excludes molecules like benzenehexol (benzene with an alcohol group on each carbon rather than a hydrogen) which are considered organic. A solid definition of an organic molecule is not certainly agreed. Just remember that: all organic molecules contain carbon but not all carbon containing molecules are organic.</span>
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