Cells

• Mitochondria are the powerhouses of the cell, producing energy through cellular respiration.
• The modern cell theory includes:

  • The cell is the smallest living unit in all organisms
  • All living things are made of one or more cells
  • All cells come from other pre-existing cells
• Cells can be divided into prokaryotes and eukaryotes

  • Prokaryotes (pro rhymes with no) have no nucleus and no membrane-bound organelles
  • Eukaryotes (eu rhymes with do) have membrane-bound organelles
• Cell membrane is selectively permeable and maintains homeostasis by controlling what goes in and out of the cell
• Cytoplasm is a jelly-like material that surrounds internal cell structures and provides support for organelles
• Ribosomes are not membrane-bound organelles and are responsible for making proteins
• In eukaryotes, the nucleus holds genetic material (DNA) and controls cell activities

  • Nucleus has a nucleolus where ribosomes are produced
• Endoplasmic reticulum (ER) processes molecules, transports them, and can be rough (with ribosomes) or smooth (without ribosomes)

  • Rough ER is involved in protein production and transporting
  • Smooth ER can detoxify and make lipids
• Golgi apparatus receives molecules from ER, modifies them, sorts them, and determines where to send them

  • Golgi apparatus can send molecules to the membrane for secretion
• Mitochondria produce ATP energy through cellular respiration using glucose and oxygen

  • Mitochondria are like a power plant for the cell
• Plant cells have chloroplasts that perform photosynthesis to make glucose using light energy

  • Chloroplasts have a pigment that captures light energy and reflect green light
• Plant cells have a cell wall for additional protection and shape maintenance that animal cells do not have
• Vacuoles in cells can act as storage of materials

  • Plant cells can have a central vacuole while animal cells can have several smaller vacuoles
• Proteins are made based on DNA instructions in the nucleus, produced by ribosomes, and can be sent out of the cell through vesicles from the Golgi apparatus
• Bacterial cells and fungal cells are very different cell types
• Prokaryotes are unicellular organisms and can be bacteria and archaea
• Eukaryotes may be protists, plants, animals, or fungi and can be unicellular or multicellular
• Prokaryotic cells have no nucleus to contain their DNA
• Prokaryotic cells have no membrane-bound organelles
• Eukaryotic cells have a nucleus to contain their DNA
• Eukaryotic cells are more complex and larger than prokaryotic cells
• Eukaryotic cells have different types of membrane-bound organelles depending on the cell type
• All living things are made of one or more cells
• Prokaryotic cells and eukaryotic cells both have DNA, ribosomes, cytoplasm, and a cell membrane
• Many eukaryotic cells, like plant and fungus cells, can have cell walls
• Animal cells are an example of eukaryotic cells that do not have cell walls