Answer:
Ions are atoms with a positive or negative charge.
Explanation:
Ions are atoms or molecules that, when subjected to the phenomenon of ionization, gain or lose electrons, ceasing to be neutral and acquiring an electric charge.
The charge that atoms or molecules possess can be positive —if it has lost electrons— or negative when it acquires electrons. The negatively charged particle is called anion, and when it is positively charged cation.
The other options are not correct because of:
- <em>There are usually as many or more neutrons than protons.
</em>
- <em>Uncharged atoms are neutral.
</em>
- <em>The number of protons or neutrons does not affect the electric charge of the atom.</em>
- <em>Atoms that joined in fixed proportions can form molecules.</em>
Answer:
Explanation:
This is usually because when they first became fossils, they embedded into the ground. Over many years afterwards, more layers came to cover that layer and so on. Newer fossils would be embedded into newer layers. That's why the older ones tend to be found the deeper you look.
Answer:
Properties of life include the use of <u><em>energy</em></u> to power an organisms activities.
Explanation:
Energy is the driving force which allows every cell to perform its functions. Organisms like humans tend to gain energy by the process of cellular respiration. Cellular respiration can be described as a process in which organisms make carbon dioxide and water from glucose (from food) and oxygen (from air). Huge amounts of ATP is also released during this process. In plants, the process of photosynthesis and cellular respiration supplies them with the energy sources.
-Plant cells are more rigid due to the cell wall.
Answer:
a) Natural selection may lead to the evolution of prezygotic reproductive isolation in organisms that already have postzygotic isolation to prevent wasted reproductive effort
Explanation:
Prezygotic reproductive isolation produces postzygotic reproductive isolation because this mechanism lead to genetic differences that impair the pairing of homologous chromosomes during meiosis.