CHAPTER 7 –
CELL STRUCTURE AND FUNCTION
7-1 Life is Cellular
Can anyone explain what “life is cellular” means?
Discovery of the cell
Robert Hooke
 The study of cells is known
as cytology.
 Cytology began in 1665,
when Robert Hooke, an
English scientist, first
glimpsed into the
microscopic world of cells
by examining dead cork
cells
 All Hooke was able to
observe were the thick
walls that surrounded
each cell.
Theorize how Mr.
Hooke came up with
the name of “cells”
Discovery of the cell
Anton Van Leeuwenhoek - 1674
 Observed living organisms
in pond water
Cell Pioneers – Cell
Theory
 During the next 170 years, other scientists used
microscopes to further advance their
knowledge of cells.
 Matthias Schleiden - 1838
 Concluded that all plants are made of cells
 Theodore Schwann – 1839
 Concluded that all animals are made of cells
 Rudolph Virchow - 1858
 Said that cells come from cells
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)
 Does have – DNA, cell wall, cytoplasm and ribosomes
 DO NOT have - a Nucleus, Membrane bound organelles
 Examples: bacteria
 Eukaryotes (eukaryotic cells)
 Cells that DO have a nucleus and other organelles
 Examples: plant cells and animal cells
Prokaryotes:
Both:
Eukaryotes:
-No nucleus
-no membrane bound
organelles
-bacteria
-cell wall
-cytoplasm
-ribosomes
-DNA
-nucleus
-membrane bound organelles
-plants/animals/fungi/protists
Identify What kind of cell
Identify What kind of cells
Identify What kind of cell
Identify What kind of cell
CELL STRUCTURES
Chapter 7
Sections 1 & 2
Cell Structures
 Specialized structures that perform specific functions in the cell are
called organelles.
 Organelle means “little organ”.
Example how to take notes:
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: Rigid wall that
surrounds the cell.
4 – Function - How does your picture connect to the function of the cell part?
Example: the cell wall protects and supports the cell. It also helps control what
comes in and out
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; selectively permeable;
support and protection
 Type of Cell: found in all cells
 Analogy: it is like the Shipping/receiving department of a factory
Monday 1/30
 Explain the differences between eukaryotes and
prokaryotes.
 Identify the organelle that acts as the
“Shipping/receiving department ” of the cell
Prokaryotes:
Both:
Eukaryotes:
-No nucleus
-no membrane bound
organelles
-bacteria
-cell wall
-cytoplasm
-ribosomes
-DNA
-nucleus
-membrane bound organelles
-plants/animals/fungi/protists
Monday 1/30
 Explain the differences between eukaryotes and
prokaryotes.
 Identify the organelle that acts as the
“Shipping/receiving department ” of the cell
Cell Membrane
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
 Physical Description: large organelle that is usually near
the center; contains the cell’s genetic material (DNA)
 Function: Controls the cells activities
 Type of Cell: found in 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 eukaryotes
 Analogy: it is like the office of a factory
Nucleolus
 Physical Description: small, dense region in the center of
the nucleus
 Function: produces ribosomes
 Type of Cell: found in eukaryotes
 Analogy: it is personnel department (the people who hire
workers) for a factory
Identify What organelle is called
the “air of the factory.” Site for
chemical reactions
Cytoplasm
Identify What organelle protects and
supports the cell. Not found in
animal cells
Cell wall
Identify What organelle Produces
ribosomes; It is sometimes called
the “Personnel” department of the
Nucleolus
cell
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 CELLS
 Analogy: it is like the workers in a factory
Endoplasmic Reticulum (ER)
 Physical Description: internal membrane system
 2 Types:
 Rough—has ribosomes
 Smooth—NO ribosomes
 Function:
 Rough—modifies proteins
 Smooth—assembles components of the cell membrane
 Type of Cell: found in eukaryotes
 Analogy: it is like the assembly line of a factory
Tuesday
1/31
Get a folder from Mr. Rogers’ Desk
Put your name on the front right corner and wait for
instruction
Golgi Apparatus (aka Golgi Body)
 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 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/maintenance crew of a factory
Vacuole / Vesicle
 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 closet of a factory
Mitochondria
 Physical Description: “bean-shaped” organelle that has a
folded inner membrane (called cristae)
 Function: use FOOD to make high-ENERGY compounds for
use by the cell; SITE OF CELLULAR RESPIRATION
 Type of Cell: found in 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
Centrioles
 Physical Description: bundles of microtubules
 Function: part of the cytoskeleton that aids in cellular
division
 Type of Cell: found only in animal cells
 Analogy: it is like the cranes used to move things in 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 cell’s 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
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
Cells Alive Website
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)
POPQUIZ
Quick Quiz
 1. Organelle that is the internal membrane system. It also
has ribosomes and modifies proteins.
A. Golgi Apparatus
B. Lysosome
C. Rough ER
D. Smooth ER
Quick Quiz
 2. Organelle that attaches carbohydrates and lipids to
proteins; gives proteins the “address” of their final
destination. Mail room of cell
A. Golgi Apparatus
B. Lysosome
C. Rough ER
D. Smooth ER
Quick Quiz
 3. Which one of the following is not a part of the cell theory
A. All living things are composed of cells.
B. All plant cells have a cell wall
C. Cells are the basic units of structure and function in living
things
D. New cells are produced from existing cells.
Quick Quiz
 4. Organelle that breaks down lipids, carbohydrates, and
proteins into useable molecules; break down old or damaged
organelles
A. Cell membrane
B. Lysosome
C. Nucleus
D. Vacuole
Quick Quiz
 5. Organelle that is usually near the center; contains the cell’s
genetic material (DNA) a boss controls his/her employees
A. Cell membrane
B. Lysosome
C. Nucleus
D. Vacuole
Quick Quiz
 Answers
1. C
2. A
3. B
4. b
5. C