Eukaryotic
Cell Structure & Function
Figure 7-5 Plant and Animal Cells
Plant Cell
Section 7-2
Smooth endoplasmic
reticulum
Vacuole
Ribosome
(free)
Chloroplast
Ribosome
(attached)
Cell
Membrane
Nuclear
envelope
Cell wall
Nucleolus
Golgi apparatus
Nucleus
Mitochondrion
Rough endoplasmic reticulum
Plant Cell
Figure 7-5 Plant and Animal Cells
Animal Cell
Section 7-2
Nucleolus
b
Nucleus
a
Ribosome
c
(attached)
Nuclear
k
envelope
Ribosome
d
(free)
Cell
e
Membrane
Mitochondrion
f
Smooth
endoplasmic
g
reticulum
Rough
endoplasmic
j
reticulum
Centrioles
h
i
Golgi apparatus
Animal Cell
Function
The Cell Theory
• All living things are composed of cells
• Cells are the basic units of structure &
function in living things
• New cells are produced from existing cells
Organelles & Cell Division
• Cells are made of specialized structures known
as organelles
• Cell biologists divide cells into 2 parts
– Nucleus
– cytoplasm
Cell Membrane (plant & animal)
• Separates inside of cell from the outside
• Phospholipid bilayer and proteins
Cytoplasm (plant & animal)
• Fluid part of the cell that is outside the
nucleus
• Houses the organelles
Nucleus (plant & animal)
• Control center
• Surrounded by nuclear envelope
– 2 membranes with pores
• Allows for movement of information into & out of the
nucleus
• Visible material = chromatin
– DNA bound to protein
• Nucleolus – small dense region where
ribosome assembly begins
Ribosomes (plant and animal)
• Small particles of RNA & proteins found
through out the cytoplasm
• Proteins are made on the ribosomes
– Follow coded instructions from the nucleus
Endoplasmic Reticulum (both)
• Internal membrane system
• lipid components of cell membrane are
assembled
• proteins & other materials are exported from
the cells
Rough & Smooth ER (both)
• Rough ER – involved in protein synthesis
– b/c has ribosomes on surfaces
• Smooth ER – has collections of enzymes
performing specialized tasks
– b/c NO ribosomes
Golgi Apparatus (both)
• Looks like a stack of closely apposed
membranes
• Modify, sort & package proteins & other
materials from ER
• Proteins are shipped from here to their final
destination
Lysosomes (plant and animal)
• Small organelles filled with enzymes
• Gets rid or the “junk”
– Digestion of:
•
•
•
•
Lipids
Carbohydrates
Proteins
Breaks into small molecules to be used by cell
– Break down old organelle
Vacuoles (plant & animal)
• A saclike structure
• A storage place for:
– Water
– Salts
– Proteins
– Carbohydrates
• In plant cells: single, large, provides support
b/c of pressure
Mitochondria (plant & animal)
• The power house
• Convert chemical energy in food into
compounds that are more convenient for cells
• Enclosed by 2 membranes
• Contains it own DNA molecules
• Come from MOM
Chloroplasts (plant only)
• Capture energy from sunlight
• Convert it to chemical energy through
photosynthesis
• Surrounded by 2 membranes
• Contains chlorophyll
• Contains small DNA molecules
Cell Wall (plant only)
• Made of cellulose
• Provides support and
structure
• Surrounds the cell
membrane
Cytoskeleton (plant & animal)
• A system of protein filaments structures
– Provide supports & organization
– Involved in movement
• Microfilaments
• Microtubules
Microfilaments
• Thread like structures made of actin
– Protein
• Tough but flexible
• Movement caused by assembly & disassembly
of these structures
– Allows for crawling such as amoebas
Microtubules
• Hollow structures made of tubulins
– Proteins
• Maintain shape
• Important for cell division
– Form centrioles -- help to organize cell division
• Form projections – cilia & flagellum
– Rapid swimming through liquids
Function
What structures are found in plant
cells but not animal cells? Why are
these structures important for plants?
What are prokaryotic cells?