Reproduction is very important for the organisms. The organisms reproduce to produce young ones like them. It helps to carry on their generation. If reproduction does not take place, no living being will survive on the earth.
The correct answer is protons and electrons.
Atoms are made of particles called protons (p+), neutrons (n0), and electrons (e-).
Protons and neutrons are located in the center of the atom, making up the nucleus and electrons surround the nucleus.
The charge on the proton and electron are exactly the same size but opposite and their number in the atom is the same when we talk about neutral atoms. Ions are charged atoms, so the number of their electrons and protons are different (for example, positive ions have more protons).
Answer:
The earth’s crust is broken into separate pieces called tectonic plates (Fig. 7.14). Recall that the crust is the solid, rocky, outer shell of the planet. It is composed of two distinctly different types of material: the less-dense continental crust and the more-dense oceanic crust. Both types of crust rest atop solid, upper mantle material. The upper mantle, in turn, floats on a denser layer of lower mantle that is much like thick molten tar.
Each tectonic plate is free-floating and can move independently. Earthquakes and volcanoes are the direct result of the movement of tectonic plates at fault lines. The term fault is used to describe the boundary between tectonic plates. Most of the earthquakes and volcanoes around the Pacific ocean basin—a pattern known as the “ring of fire”—are due to the movement of tectonic plates in this region. Other observable results of short-term plate movement include the gradual widening of the Great Rift lakes in eastern Africa and the rising of the Himalayan Mountain range. The motion of plates can be described in four general patterns:
<p><strong>Fig 7.15.</strong> Diagram of the motion of plates</p>
Collision: when two continental plates are shoved together
Subduction: when one plate plunges beneath another (Fig. 7.15)
Spreading: when two plates are pushed apart (Fig. 7.15)
Transform faulting: when two plates slide past each othe
Explanation: