Transcript The Building Blocks of Life

Cell Structures
The Cell Theory
 All
living things are composed of
cells.
 Cells are the basic units of
structure and function in living
things.
 New cells are produced from
existing cells.
2 Basic Types of Cells
 Prokaryotes
(prokaryotic cells)
– Cells that DO NOT have a nucleus
– Examples: bacteria
 Eukaryotes
(eukaryotic cells)
– Cells that DO have a nucleus and
other organelles
– Examples: plant cells and animal
cells
Cell Structures
 Specialized
structures that perform
specific functions in the cell are
called organelles.
 Organelle means “little organ”.
1 - Name: Cell Wall
2 - Picture – this should be an illustration that shows
what the structure does; what is the function of the
structure? NOT a picture straight from textbook.
3 - Description of the picture that you came up with;
Example: the offensive line protects the quarterback.
4 – Function - How does your picture connect to the
function of the cell part? Example: the cell wall is like
the walls of the factory because it supports and
protects the factory.
5 - Type - Plant or Animal cell; Prokaryote or
Eukaryote; Example: found in all prokaryotes, fungi
and, plant cells; NOT found in animal cells!!!
Cell Membrane
 Physical
Description: thin, flexible
barrier around the cell (just inside
the cell wall OR the outside border of
animal cells)
 Function: controls what enters and
leaves the cell; support and
protection
 Type of Cell: found in all cells
 Analogy: it is like the security guard
of a factory
Cytoplasm
 Physical
Description: the fluid-like
material inside the cell membrane
 Function: contains the organelles;
“cell jelly”
– Site for chemical reactions
 Type
of Cell: found in all cells
 Analogy: it is like the air of a factory
Nucleus
Physical Description: large organelle that
is usually near the center; contains the
cell’s genetic material (DNA) a boss
controls his/her employees
 Function: controls the cells activities and
 Type of Cell: found in all eukaryotes
 Analogy: it is like the boss of a factory

Nuclear Membrane
(aka Nuclear Envelope)
 Physical
Description: double layered
membrane that surrounds the
nucleus; has pores
 Function: Protects the nucleus; pores
allow material in and out of the
nucleus.
 Type of Cell: found in all eukaryotes
 Analogy: it is like the office of a
factory
Endoplasmic Reticulum (ER)
 Physical
Description: internal
membrane system
 2 Types: Rough—has ribosomes
Smooth—NO ribosomes
 Function: Smooth—assembles
components of the cell membrane;
Rough—modifies proteins
 Type of Cell: found in all eukaryotes
 Analogy: it is like the assembly line
of a factory
Ribosomes
 Physical
Description: very small,
round structures either attached to
the endoplasmic reticulum or free
(floating in the cytoplasm)
 Function: makes proteins
 Type of Cell: found in all eukaryotes
AND some prokaryotes
 Analogy: it is like the workers in a
factory
Golgi Apparatus
 Physical
Description: stack of
membranes in the cytoplasm
 Function: attaches carbohydrates
and lipids to proteins; gives proteins
the “address” of their final
destination
 Type of Cell: found in all eukaryotes
 Analogy: it is like the mailroom or
packaging department of a factory
Lysosome
 Physical
Description: small, round
sacks in the cytoplasm
 Function: breaks down lipids,
carbohydrates, and proteins into
useable molecules; break down old
or damaged organelles
 Type of Cell: found in all eukaryotes
BUT are very rare in plant cells
 Analogy: it is like the janitor of a
factory
Vacuole
 Physical
Description: large, spacious
sack in the cytoplasm
 Function: stores materials for the cell
(water, food, waste, etc…)
 Type of Cell: found in all eukaryotes
(usually one large vacuole in plants
and many small vacuoles in animals)
 Analogy: it is like the storage
warehouse of a factory
Mitochondria
 Physical
Description: “bean-shaped”
organelle that has a folded inner
membrane (called cristae)
 Function: use FOOD to make highENERGY compounds for use by the
cell
 Type of Cell: found in all eukaryotes
 Analogy: it is like the power plant or
coal-burning furnace of a factory
Chloroplast
 Physical
Description: tubular
organelle that contains chlorophyll (a
green pigment)
 Function: use energy from
SUNLIGHT to MAKE FOOD molecules
through photosynthesis
 Type of Cell: found in plant cells
 Analogy: it is like the cafeteria OR
solar energy panels of a factory
Cytoskeleton
 Physical
Description: a network of
protein filaments in the cytoplasm;
made of microtubules and
microfilaments
 Function: helps support the cell and
maintain its shape; moves organelles
within the cell; aids in cell movement
 Type of Cell: found in all cells
 Analogy: it is like the support beams
and cranes of a factory
Centrioles
 Physical
Description: bundles of
microtubules
 Function: part of the cytoskeleton
that aids in cellular division
 Type of Cell: found in animal cells
 Analogy: it is like the cranes used to
move things in a factory
Plant Cells vs. Animal Cells
 Cell
Wall
 Chloroplasts
 No Centrioles
 Lysosomes are
rare
 1 Large Vacuole
 No
Cell Wall
 No Chloroplasts
 Centrioles
 Lysosomes are
common
 Several Small
Vacuoles
Animal Cell
Plant Cell
Job of Cells
The
main job of all cells is to
make proteins
 Different
cells make different types
 Protein production:
– Ribosome 
– Endoplasmic Reticulum 
– Golgi Apparatus 
– Final Destination of the Protein
(may be outside of the cell)