Chapter 4
Cell Structure
By Boundless
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A cell is the smallest unit of a living thing and is the basic building block of all organisms.
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Microscopes allow for magnification and visualization of cells and cellular components that cannot be seen with the naked eye.
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Cell theory states: living things are composed of one or more cells; the cell is the basic unit of life; cells arise from existing cells.
Cell size is limited in accordance with the ratio of cell surface area to volume.
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A eukaryotic cell has a true membrane-bound nucleus and has other membranous organelles that allow for compartmentalization of functions.
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The plasma membrane is made up of a phospholipid bilayer that regulates the concentration of substances that can permeate a cell.
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Found within eukaryotic cells, the nucleus contains the genetic material that determines the entire structure and function of that cell.
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Mitochondria are organelles that are responsible for making adenosine triphosphate (ATP), the cell's main energy-carrying molecule.
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Although they are both eukaryotic cells, there are unique structural differences between animal and plant cells.
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Vesicles and vacuoles are membrane-bound sacs that function in storage and transport.
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The endoplasmic reticulum is an organelle that is responsible for the synthesis of lipids and the modification of proteins.
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The Golgi apparatus sorts and packages materials before they leave the cell to ensure they arrive at the proper destination.
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Lysosomes are organelles that digest macromolecules, repair cell membranes, and respond to foreign substances entering the cell.
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Peroxisomes neutralize harmful toxins and carry out lipid metabolism and oxidation reactions that break down fatty acids and amino acids.
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Microfilaments, which are the thinnest part of the cytoskeleton, are used to give shape to the cell and support all of its internal parts.
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Microtubules are part of the cell's cytoskeleton, helping the cell resist compression, move vesicles, and separate chromosomes at mitosis.
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The extracellular matrix of animal cells holds cells together to form a tissue and allow tissues to communicate with each other.
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Intercellular junctions provide plant and animal cells with the ability to communicate through direct contact.