Presentation on theme: "Cell Structure & Function (What do cells look like?) (What do cells do?)"— Presentation transcript:
Cell Structure & Function (What do cells look like?) (What do cells do?)
2 main types of cells Prokaryotes (Prokaryotic) Eukaryotes (Eukaryotic)
Prokaryotes Simple cells Unicellular only Typical size 1-2 μm in diameter No nuclear membrane or other membrane- bound organelles DNA is in a tangled loop Some prokaryotes have a second loop of DNA called a plasmid Cell walls vary but can be very “tough” to help the cell survive harsh environments
Eukaryotes Complex cells Both unicellular & multicellular organisms. (All multicellular organisms are this type.) Typically about 10x larger than prokaryotic cells Many organelles – some common, some only in plant cells, some only in animal cells DNA is extremely long so the cell condenses it to form chromosomes Some eukaryotic cells differentiate. This means they can become different types of cells: skin cells, muscle cells, blood cells, fat cells, etc. Plants have different types of cells too.
Comparing prokaryotes to eukaryotes Prokaryotic cellEukaryotic cell Simple or Complex? Size of Cell? Unicellular, Multicellular, or Both Any membrane-bound organelles? What does the DNA look like?
Comparing prokaryotes to eukaryotes Prokaryotic cellEukaryotic cell Simple or Complex?SimpleComplex Size of Cell? 1 – 2 μm Typically 10x larger Unicellular, Multicellular, or BothUnicellularBoth Any membrane-bound organelles?NoYes What does the DNA look like? Tangled loop Chromosomes
Organelles Little “organs” inside cells. Only found in eukaryotic cells. Each type of organelle has its own purpose/function for the cell. Organelles may have once been prokaryotic cells that were engulfed and then incorporated into a larger cell instead of being broken down as food.
Nucleus Holds genetic material 2007
Nuclear membrane Selects what can enter and leave the nucleus
Nucleolus An area in the nucleus that makes ribosomes
Nuclear pore Controls what molecules can enter/leave the nucleus re%20%20.jpg
Cell wall Supports and protects the cell. Root cell:
Cell membrane Selects what can enter and leave the cell.
Cytoplasm Includes the internal part of the cell except the nucleus.
Cytosol The gel-like fluid that surrounds the organelles in the cytoplasm.
Lysosomes Decomposes/digests molecules
Ribosomes Makes proteins (protein synthesis) (Tiny dots!)
Endoplasmic reticulum Transports molecules around the cell Rough E.R. has ribosomes on it Smooth E.R. lacks ribosomes
Golgi apparatus Packages molecules to be released
Mitochondria Makes ATP energy from the sugars that you ate earlier com/prod/LC/LCcellunit.html&h=238&w=416&sz=19&hl=en&start=40&tbnid=oAv7kJ4T5Z0hFM:&tbnh=72&tbnw=125&prev=/imag es%3Fq%3Dmitochondria%2BTEM%26start%3D20%26gbv%3D2%26ndsp%3D20%26svnum%3D10%26hl%3Den%26sa%3DN November 2007
Cytoskeleton Supports cells with no cell wall (cyto- means cell) Microtubules: thicker, hollow tubes Microfilaments: thinner strands of protein 3m.jpg&imgrefurl=http://www5.pbrc.hawaii.edu/allen/ch07/11-pmcyp html&h=711&w=640&sz=173&hl=en&start=3&tbnid=eKDoQPVtK0FPzM:&tbnh=140&tbnw=126&prev=/images%3Fq%3Dmicrofilaments%2BTEM%26gbv %3D2%26svnum%3D10%26hl%3Den
Centrioles Helps the cell divide View of one centriole from the end. _TEM.jpg/180px-Spindle_centriole_-_embryonic_brain_mouse_-_TEM.jpg
Chloroplasts Converts light to sugar molecules (photosynthesis)
Where to find these organelles: Cell Wall Cell membrane Nucleus Nuclear membrane Nucleolus Nuclear pore Endoplasmic reticulum Golgi apparatus RibosomesLysosomesVacuolesCentriolesMitochondriaChloroplastsCytoplasmCytosol Cytoskeleton: microstubules Cytoskeleton: microfilamanets Plant cells only Animal cells only All eukaryotic cells
Where to find these organelles: Cell Wall Cell membrane Nucleus Nuclear membrane Nucleolus Nuclear pore Endoplasmic reticulum Golgi apparatus RibosomesLysosomesVacuolesCentriolesMitochondriaChloroplastsCytoplasmCytosol Cytoskeleton: microstubules Cytoskeleton: microfilamanets Plant cells only XX Animal cells only XXX All eukaryotic cells XXXXXXXXXXXXX
Plant Cell & Animal Cell Plant CellAnimal Cell
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