Cell Structure and Function
Chapter 5
Organelles
• There are many small structures
located inside the cell.
• These structures are called
organelles (little organs).
• These organelles perform functions
that keep the cell alive.
• Some organelles are found only in
plant cells, and only in animal
cells.
Do Now!
•Answer questions in
UPCO page 65, # 1,2.
Cell Membrane
• Also called plasma membrane.
• Acts as a barrier between the cell and
the outside environment.
• Maintains the shape of the cell.
• Protects the cell.
• Is a phospholipid bi-layer (fluid
mosaic model).
• Is semi-permeable (allows only
certain things in or out of the cell).
• Aids in maintaining homeostasis.
Cell Membrane
Do Now !
Answer questions in
UPCO, page 67, # 1,2
(top).
Cell Membrane- Let’s
go to the Video
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Passive Transport
• Is the passage if materials into and out
of the cell without the use of energy.
• Most commonly involves Diffusion.
• Osmosis is diffusion through water.
• Diffusion is the movement of molecules
from an area of higher concentration to
an area of lower concentration.
• Equilibrium is reached when the two
areas (high and low concentration)
become equal concentrations.
• The concentration gradient is the
difference between the concentration of
two areas.
Let’s go to the Video!
QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
Active Transport
• Cellular energy is used to move
particles through a membrane.
• This movement is from lower
concentration to higher concentration.
• It is against the concentration gradient.
• Pinocytosis- large dissolved molecules
are taken into the cell.
• Phagocytosis- large undissolved
molecules are taken into the cell.
Let’s go to the Video!
QuickTime™ and a
Cinepak decompressor
are needed to see this picture.
Pinocytosis
• A type of active
transport.
• Large dissolved
molecules taken
into the cell by
formation of
vacuoles.
• C.M. forms an
indentation and
pinches off w/ the
dissloved
molecule and
forms a vacuole.
Phagocytosis
• A type of active
transport.
• Large undissloved
molecules are
taken into the
cell.
• Cytoplasm flows
around the
particles and
engulfs them.
Let’s go to the Video!
Surface to volume ratio:
QuickTime™ and a
Sorenson Video decompressor
are needed to see this picture.
Cytoplasm
• Jelly-like substance inside
the cell.
• Gives the cell it’s shape.
• Contains the organelles.
• It is located between the
C.M. and the Nucleus.
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
•Answer questions 1-3,
on page 67 in UPCO.
Nucleus
• Large round structure located
inside the cytoplasm.
• Contains genetic material
(DNA).
• Has a nuclear membrane
(semi-permeable).
• Contains a Nucleolus (makes
Ribosomes).
• Controls the activity of the cell.
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
•Answer questions 1-3, on
page 68 (top) in UPCO.
Mitochondria
• The “powerhouse” of the cell.
• Function in Cellular
Respiration.
• Produce energy in the form of
ATP (adenosine triphosphate).
• Have DNA.
• Folded inner membranes are
called Cristae.
Mitochondria
Let’s Go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
Answer questions 1-8 on
page 69 in UPCO.
Chromosomes
•Long thread-like
structures found in the
nucleus of the cell.
•Contain hereditary info.
•Genes are hereditary
units made up of DNA.
Chromosomes
Do Now!
Answer questions 1,2 on
page 68 (bottom) in
UPCO.
Endoplasmic
Reticulum
• A system of channels or
canals w/i the cytoplasm,
that transports materials.
• Smooth E.R. has no
ribosomes on it.
• Rough E.R. has ribosomes.
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
Answer questions 1,2 on
page 70 (top) in UPCO.
Ribosomes
•Make proteins.
•Can be found attached to
the E.R., or floating
freely in the cytoplasm.
Do Now!
Answer questions 1,2 on
page 70 (middle) in
UPCO.
Golgi Complex
• A stack of membrane bound
channels and vacuoles.
• They synthesize, package,
and secrete cell products
(proteins).
Golgi Complex
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
Answer question 1 on
page 70 (bottom).
Vacuoles
•Sac-like structures.
•Store food, water,
wastes.
•Located in the cytoplasm.
•Plants have a large
central vacuole.
Vacuoles
Do Now!
Answer question 1 on
page 71 (top).
Lysosomes
•Membrane bound sacs.
•Contain digestive
enzymes.
•Destroy damaged or old
cell parts, invading
pathogens.
Lysosomes
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
Answer question 1 on
page 71 (middle) in
UPCO.
Chloroplasts
• Organelle involved with the
manufacture of food in plants.
• Located in the cytoplasm.
• Contain Chlorophyll (green
pigment).
• Contains enzymes, grana,
stroma.
• Function during
photosynthesis.
Chloroplasts
Do Now!
Answer questions 1-7 on
page 72 in UPCO.
Centrioles
•Found in animal cells.
•Function during cell
division.
•Look like cylinders and
are found in pairs near
the nucleus.
Centrioles
Do Now!
Answer question 1 on
page 72 in UPCO
(bottom).
Cell Wall
•Found only in plant cells.
•Made up Cellulose, a
non- living material.
•Protects and shapes the
cell.
Do Now!
Answer questions 1,2 on
page 73 in UPCO.
Comparing Plant & Animal Cells
Do Now!
Answer questions 1-3 on
pages 73-74 in UPCO.
Cell Specialization
• Certain cells do certain jobs.
• Cells are very specific to what
they do.
(ex.- Blood Cells: carry O2 to
cells, Nerve Cells: carry
impulses, Muscle Cells: move
parts of an organism,
Xylem/Phloem Cell: transport
materials throughout plants).
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
Answer question 1 on
page 74 (bottom) in
UPCO.
Cell Organization
• Cells are grouped together into
units or levels.
• These specialized units
perform similar functions.
• Groups of cells make up
tissues, groups of tissues make
up organs, groups of organs
make up organ systems,
groups of organ systems make
up an organism.
Let’s go to the Video!
QuickTime™ and a
Sorenson Video 3 decompressor
are needed to see this picture.
Do Now!
Answer questions 1-4 on
page 75 in UPCO.