Introduction to Cells
• Before the 17th century, no one knew cells existed because they were too small to be seen with the
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unaided human eye.
In the early 17th century, _______________________ were invented which made it possible to see cells
for the very first time.
Anton Von Leeuwenhoek made the ___________ hand-held microscope and viewed microscopic
organisms in water and bacteria from his teeth.
In 1665, Robert Hooke made an improved microscope and viewed thin slices of __________ where he
saw plant cell walls. He names what he saw _____________.
The Cell Theory
The combined work of scientists Schleiden, Schwann, & Virchow is known as the Cell Theory.
Principles of the Cell Theory
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Cell Diversity
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Not all cells are alike
Cells differ in _______________________________________________________.
The female ______ ________ is the largest cell in the body & can be seen without a microscope
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________________ cells are some of the smallest cells & are only visible with a microscope.
Cells come in a variety of shapes, & the shape helps
determine the function of the cell
(e.g. Nerve cells are long to transmit messages in the body, while red
blood cells are disk shaped to move through blood vessels)
Basic Structure of a Cell
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Basic types of cells
Number of Cells
Organisms may be:
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–composed of one cell
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-composed of many cells
Cells May be Prokaryotic or Eukaryotic
__________________________ include _______________ & have NO ______________ or membranebound ____________________.
 _________________________ include most other cells and _____ have a nucleus & membranebound organelles.
Prokaryotic Cells
• Kingdoms:
1.
Monera (Eubacteria)
2.
Archaea (Archaebacteria)
• Characteristics:
1.
are usually _____________ and _______________ than eukaryotes
2.
have NO ______________ or membrane-bound ____________________.
3.
contains a ____________________________ and a ______________________.
Prokaryotes
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Eukaryotic Cells
• Kingdoms:
1.
Protista
2.
Fungi
3.
Plantae
4.
Animalia
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Characteristics:
1.
_____________ a nuclear membrane
2.
_____________ membrane-bound organelles
Eukaryotic Cell
Contain 3 basic cell structures:
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Two Main Types of Eukaryotic Cells
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Plasma (Cell) Membrane
 The boundary of every cell.
 Is said to be ________________________________ because it controls what _______________________
the cell.
 Made of _________________ and _____________________________.
 Other Names:
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Cell Wall
 Main function =
 Located outside the cell membrane
 Found in ____________ and __________ (nearly all eukaryotes but NOT ______________ cells).
 Plant cell wall made out of ______________.
 Fungi cell wall made out of ______________.
 Bacteria cell wall made out of ________________________.
Cytoplasm
 _______________________ substance that holds ________________ in place.
 Entire region between the _____________________________ and the ___________________________.
Cytoplasm
Nucleus
 Only found in _____________________.
 Contains the ___________________________________________.
 Called the _____________ of the cell because it ______________
all cell activities.
Vacuoles
 Large membrane-closed sac used for __________________________.
 Contains ____________, sugars, proteins, and nutrients.
 Called the ________________________ in plant cells because it is much larger.
Other Organelles Found in Cells
 ______________ - makes ribosomes
 ____________________________ - packages and
ships proteins (modifes, stores, and transports
products from the ER to the plasma membrane).
___________________ - site of protein synthesis
___________________ - digests old
worn out cell parts; filled with digestive enzymes
Smooth & Rough Endoplasmic Reticulum
 __________________ - has no ribosomes and makes proteins used in the cell.
 __________________ - HAS ribosomes on its surface and ________________ ribosomes
Mitochondria
 Found in both __________ and _____________ cells.
 Is the site of ___________________________________, a process that uses energy extracted from
organic macromolecules to produce _________ (_______________).
 Also known as the _______________________.
 Has a _____________ membrane.
 Has its own ________.
Chloroplast
 Found in photosynthetic _____________ cells.
 Is the site of ______________________, a process that uses _________ energy (sun) and water to
produce organic macromolecules ( __________________).
Cytoskeleton
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Network of protein filaments that help the cell to maintain its ____________.
Aids in cellular support and _____________________.
Composed of two components:
1.
Microtubules – hollow tubes of proteins, can serve as ___________ along which
organelles move.
2.
Microfilaments - long, thin fibers that function in the ____________________ and
_____________ of cells.
Cilia, Flagella, Pseudopodia
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Extensions of the ______________________________.
Aids in movement…
Cilia =
Flagella =
Pseudopodia =
Differences between plant cells and animal cells
ANIMAL CELLS
PLANT CELLS
Levels of organization
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Cells are grouped together and work as a whole to perform special functions