Answer:
Explanation:
Some cells also feature orderly arrangements of molecules called organelles. Similar to the rooms in a house, these structures are partitioned off from the rest of a cell's interior by their own intracellular membrane. Organelles contain highly technical equipment required for specific jobs within the cell. One example is the mitochondrion — commonly known as the cell's "power plant" — which is the organelle that holds and maintains the machinery involved in energy-producing chemical reactions (Figure 3).
A pie slice diagram shows the proportion of water to typical chemical components in a bacterial cell. Each chemical component is color-coded and is labeled by name and percent.
Figure 2: The composition of a bacterial cell
Most of a cell is water (70%). The remaining 30% contains varying proportions of structural and functional molecules.
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Figure Detail
A diagram of scale shows how different biological features fall along a size gradient. Atoms are represented on the far left side of the scale, while much larger blood vessels are pictured on the far right; molecules, organelles, and cells are arranged in the middle in order of increasing size, between these two extremes.
Figure 3: The relative scale of biological molecules and structures
Cells can vary between 1 micrometer (μm) and hundreds of micrometers in diameter. Within a cell, a DNA double helix is approximately 10 nanometers (nm) wide, whereas the cellular organelle called a nucleus that encloses this DNA can be approximately 1000 times bigger (about 10 μm). See how cells compare along a relative scale axis with other molecules, tissues, and biological structures (blue arrow at bottom). Note that a micrometer (μm) is also known as a micron.
