Section 2
Vocabulary – Need 14 Cards
 1. organelle
 A tiny cell structure that carries out a specific function
within the cell.
 2. Cell wall
 A rigid layer of nonliving material that surrounds the
cells of plants and some other organisms.
 3. cytoskeleton
 A protein “framework” inside a cell that gives the cell a
shape.
Vocabulary – Need 14 Cards
 4. cell membrane
 The outside cell boundary that controls which
substances can enter or leave the cell.
 5. nucleus
 The control center of a eukaryotic cell that directs the
cell’s activities and contains the information that
determines the cell’s form and function.
 6. cytoplasm
 The material within a cell apart from the nucleus.
Vocabulary – Need 14 Cards
 7. mitochondria
 Rod shaped cell structures that convert energy in food
molecules to energy the cell can use to carry out its
functions.
 8. endoplasmic reticulum
 A cell structure that forms passageways in which
proteins and other materials are carried through the cell.
 9. ribosome
 A small grain-like structure in the cytoplasm of a cell
where proteins are made.
Vocabulary – Need 14 Cards
 10. Golgi body
 A structure in a cell that receives proteins and other
newly formed materials from the endoplasmic
reticulum, packages them, and distributes them to other
parts of the cell.
 11. chloroplast
 A structure in the cells of plants and some other
organisms that captures energy from sunlight and uses it
to produce food.
 12. vacuole
 A sac inside a cell that acts as a storage area.
Vocabulary – Need 14 Cards
 13. lysosome
 A small, round cell structure containing
chemicals that break down large food particles
into smaller ones. They also break down old cell
parts and release the substances so they can be
used again.
 14. interact (in tur AKT) v.
 To act upon one another.

Most people interact with other employees at work.
Division of Labor
How are jobs in a town
divided up among people?
Why is it effective to
divide the labor in this
way?
Cell wall and Cell membrane
 When Hooke observed cork cells, what he saw was the
cell wall.
 Look at and read the caption for Figure 5.
 What shape do the cell walls give to the onion root cells?

Rectangular
 What is the function of the cell wall?
 It helps protect and support the cell.
 What is the function of the cell membrane?
 It controls what substances come into and out of a cell.
Cell wall and Cell membrane
 Which of these structures do plant cells have?
 Plant cells have both a cell wall and a cell
membrane.
 Which of these structures do animal cells have?
 Animal cells only have cell membranes, not a
cell wall.
 Why does a cell with a cell wall need a cell membrane?
 The cell wall separates the cell from the outside
environment, but it cannot control all substances that
come into and out of the cell.
Plant Cell
Animal Cell
DE Videos
Parts of a Plant Cell
Parts of an Animal Cell
Venn Diagram
Plant
Cell
Animal
Cell
Homework
Study your flashcards!
Complete your
diagrams and labeling!
Functions of the Nucleus
 What is the function of the nucleus?
 The nucleus directs all of the cell’s
activities.
 What keeps material in the nucleus from
spilling out?
 The nucleus is surrounded by the nuclear
envelope.
Functions of the Nucleus
 How does the nucleus “know” how to direct
the cell?
 Thin strands of chromatin in the nucleus
contain genetic material, the instructions
for directing the cell’s functions.
 What is the nucleolus?
 It is where organelles that make proteins
are produced.
Functions of the Nucleus
 Where in the nucleus is genetic material
found?
 Genetic material is found in strands called
chromatin.
 How is the nucleus like the manager of a
company?
 How is a cookbook like the genetic code?
Cytoplasm
Cytoplasm is a clear, thick, gel-like
fluid that is constantly moving.
Inside the cytoplasm are many
organelles.
Each organelle performs a specific
function.
Mitochondria
 Known as the
“powerhouses” of the
cell because they
convert energy in
food molecules to
energy the cell can
use to carry out its
functions.
Endoplasmic Reticulum
 A cell structure that
forms passageways
in which proteins
and other materials
are carried through
the cell.
 Similar to a system
of hallways in a
building.
Ribosomes
 Small, grain-like
 Attached to the
surface of the
endoplasmic
reticulum or floating
in the cytoplasm.
 Protein producing
factories.
Golgi Bodies
 Looks like flattened sacs and




tubes.
Thought of as the cell’s mail room.
Receives proteins and other newly
produced materials from the
endoplasmic reticulum.
Then packages and distributes
materials to other parts of the cell.
Also releases material outside the
cell.
Chloroplasts
 Only plant cells (and
some other
organisms) have
chloroplasts.
 Capture energy from
sunlight and use it to
produce food.
 Make leaves green!
Vacuoles
 Water filled sac
 Floats in cytoplasm
 Storage area of the cells
 Store food, waste products, and
other needed materials.
 Plant cells have one large central
vacuole.
 Some animal cells have smaller
storage organelles
Lysosomes
 Small, round structures
 Contain chemicals that
break down certain
materials
 Break down large food
into smaller food.
 Break down old cell parts
for reuse.
 Can be considered the
cell’s “clean up crew”
Functions of Organelles
 How do ribosomes, Golgi bodies, and the
endoplasmic reticulum work together?
 Ribosomes make proteins that are
released through the endoplasmic
reticulum and moved to the Golgi bodies.
Golgi bodies move materials around and
outside the cell.
Functions of Organelles
 How do chloroplasts, mitochondria, lysosomes,
and vacuoles work together in plant cells?
 Chloroplasts capture the sun’s energy and
use it to make food for the cell. Mitochondria
convert energy in food to energy the cell can
use. Lysosomes break down materials,
including food particles. Vacuoles store food
and other materials the cell needs.
Apply
Why are chloroplasts found
only in plant cells?
Only plants have the ability
to capture energy from
sunlight and make food.
How Cells Differ
 Cells have different structures because of their
functions.
 Compare the nerve cell (Figure 11) to the red blood
cells.
 The nerve cell has extensions, and the red blood cells
look flattened.
 How do you think each cell’s shape helps it do its job?
 The extensions on nerve cells help them reach out and
send messages to other cells; the flatness of red blood
cells helps them squeeze through tiny blood vessels.
Homework
 Pg. 64 Worksheet
 Visit www.exploratorium.edu/traits/cell_explorer.html
 Write down five interesting facts that you learned.
 Write down what you liked about the website.
Project – Due Fri. Dec. 9
 Gelatin Cell: Make your own model of a cell
 Pg. 92 in your text book has directions.
 Tips
 Use a pan for a plant cell. Use a resealable plastic bag for
an animal cell.
 Use warm, not hot, water
 Stir the gelatin until it dissolves completely and chill for
up to an hour before adding the cell structures.
 Bring to class as soon as you finish to share throughout
the week with a key.