Chapter 4
The Cell In Action
Pseudomonas aeruginosa
What would happen if…
•If a factory’s power
supply was cut off or if its
supply of raw materials
never arrived?
•If the factory could never
get rid of its garbage?
•If a cell couldn’t exchange
nutrients, vital materials, and
waste with its environment
HOW DO MATERIALS MOVE IN
AND OUT OF CELLS?
Phosphoflourescent Injection of bacteria into macrophage sample
Diffusion
• Gelatin/Dye Experiment
• At first it is easy to see where the gelatin
ends and the dye begins.
• What happens over time?
• Why does this happen?
Diffusion
• The particles of dye and gelatin slowly begin to mix
because of diffusion.
• Diffusion – the movement of ______________________
_____________________________. (Until __________ is
reached or a __________ resists the process).
• Note: all substances are made of particles of varying
size
• In other words they travel from ______________ to
________________ until the crowds are ____________
______________________________________________.
Diffusion
Consider 2 rooms filled with people
Cell
Membrane
Diffusion
to
Equilibrium
Cell
Membrane
•
•
•
•
•
•
http://www.biosci.ohiou.edu/introbioslab/Bios170/diffusion/Diffusion.html
http://www.biosci.ohiou.edu/introbioslab/Bios170/diffusion/Diffusion.html
http://www.biologycorner.com/bio1/diffusion.html
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBooktransp.html#C
ells%20and%20Diffusion
http://highered.mcgraw-hill.com/olc/dl/120068/bio03.swf
http://en.wikipedia.org/wiki/Diffusion
Equilibrium
• When the concentration of a substance on
the outside of the semi-permeable
membrane ________________________
________________ on the inside of the
semi-permeable membrane.
• FACT – All organisms
need water to live
• FACT – The cells of
living organisms are
surrounded by and
filled with fluids that
are made mostly of
water.
OSMOSIS
• Osmosis – the diffusion of ________ through the
cell membrane from ______________________
________________________________________
• FACT – water is made up of particles. Pure
water has the highest concentration of water
particles.
• How would you lower the concentration of pure
water?
OSMOSIS JONES
The Cell and Osmosis
• Water particles will
move from areas of
high concentration to
areas of lower
concentration.
• The direction of flow
depends
only on the
h
level of concentration.
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
Osmosis
H2O
NaCl
Diffusion
NaCl
H2O
H2O
NaCl
Osmosis links
•
http://zoology.okstate.edu/zoo_lrc/biol1114/tutorials/Flash/Osm
osis_Animation.htm
•
http://www.stolaf.edu/people/giannini/flashanimat/transport/osm
osis.swf
•
•
http://www.tvdsb.on.ca/westmin/science/sbi3a1/Cells/Osmosis.htm
http://www.mhhe.com/biosci/esp/2001_gbio/folder_structure/ce/m3
/s3/cem3s3_3.htm
•
http://www.bbc.co.uk/education/asguru/biology/01cellbiology/05p
athways/10osmosis/index.shtml
Red Blood Cells
• Link to Red blood cell lysing
Plant Cells
Crossing Membranes Demo
• Try dried grapes – in pure water will swell
up
• - in water mixed with a lot of sugar or salt it
will shrink
• Do the iodine-water-starch demo in front of
class
• Many particles, such as water and oxygen
can diffuse though the semi-permeable
phospholipid cell membrane because of
their small size.
• But what happens to molecules that are
too large such as sugars or amino acids?
Passive and Active Transport
In order to understand these types of
transport you have to know that these
types of transport ___________________
___________________________________;
allowing particles to travel in and out.
•
1. The activities of a cell depend on
the materials that enter and leave
the cell.
2. To stay alive, a CELL MUST
EXCHANGE Materials such as
Food and Waste With Its
ENVIRONMENT.
3. These materials must cross the
Cell Membrane.
4. Small molecules like WATER,
OXYGEN, AND CARBON DIOXIDE
can move in and out freely.
5. Large molecules like PROTEINS
AND CARBOHYDRATES CANNOT.
6. The Cell Membrane is
SEMIPERMEABLE.
7. A SEMIPERMEABLE
MEMBRANE OR SELECTIVELY
PERMMEABLE ONLY ALLOWS
Certain molecules tp pass through
• Passive Transport – the diffusion of particle
through the proteins.
– ____________________________________
– ____________________________________
– (just like diffusion but can only occur at the protein
doorways)
Passive Transport
•
Active Transport
• Active Transport – the movement of
particles through the protein doorways
– ____________________________________
___________________________________
– ___________________________________
– ____________________________________
• ACTIVE TRANSPORT
- is especially IMPORTANT in
MAINTAINING ION
CONCENTRATION IN CELLS
AND BETWEEN CELLS
• http://www.bbc.co.uk/education/asguru/biol
ogy/01cellbiology/05pathways/07passivefa
cilitated/index.shtml
Other Means of Transport
• Endocytosis – the cell
membrane _________________
_________________ it in a vesicle
formed from the pinched off
circular piece of cell membrane.
• Exocytosis – ____________are
formed at the endoplasmic
reticulum or at the golgi complex
and carried to the ___________
__________ where the vesicle __
__________________ the
contents of the vesicle
MINI QUIZ
1) What part of the cell do materials pass
through to get into and out of the cell?
2) What is osmosis?
3) How do large molecules move through
the cell (and at what structure)?
Why do you get hungry?
• It’s your body’s way of telling you that your
cell’s need energy.
(Just like feeling the need to breathe it’s cells
craving oxygen)
It All Starts With the Sun
(and it all stops without the sun)
Nearly all the energy that fuels life ___________________
Its light is changed into food by plants through the process
of photosynthesis.
The food that plants make not only supplies them with
energy but also for organisms that that eat the plants.
Photosynthesis
• Occurs inside of chlorophyll which is inside
of chloroplasts
•
Light
_____________ Energy
_________________
Light
_____________ Energy
_________________
______________
_________________
Glucose
• __________________________________
___________________________________
• Carbohydrates are a storable form of
energy
Oxygen
• Necessary for all life
How is energy derived from Food?
• Food molecules (ie. Sugars) must be
__________________________________
•
This is accomplished via 2 different
processes:
1) _______________________
2) _______________________
Cellular Respiration
= aerobic respiration
– Uses _______________
– Glucose + Oxygen
________________________________
(The waste products of cellular respiration)
• Most of the energy released is in the form
of heat. The rest is ATP.
• In eukaryotes the cellular respiration takes
place in ______________________
Fermentation
= anaerobic glycolysis
- does not use oxygen
- leads to the production of small amounts
of ATP
- produces by-product = lactic acid
Mini Quiz
True or False
1) Plants and animals capture their energy
from the sun.
2) Cellular respiration describes how a cell
breathes.
3) Fermentation produces ATP and lactic
acid.
•
The Cell Cycle
In the human body, 10,000,000
new cells are produced every
minute.
The cell cycle begins when the _____________ (or after
the last division and ends _________________; at which
point it begins again.
Note: The cell cycle does not end when the cell dies.
Before a cell divides it must:
• __________________
• __________________
• Done in the process of copying the
chromosomes.
• How many chromosomes are there in a
human? Fruit Fly? A potato?
• Human -
46 chromosomes
» (23 pairs)
• Fruit Fly -
8 chromosomes
» (4 pairs)
• Potato -
48 chromosomes
» (24 pairs)
• The number of chromosomes has nothing to do
with the complexity of an organism
Question???
What does DNA code for?
Prokaryotic Cell Division
• Cell division is called ________________.
• Simple because a bacteria only has a
single circular DNA and some ribosomes
Eukaryotic Cell Division
More complex because there is so much
DNA and because the DNA incorporates
proteins into its structure.
3 stages of eukaryotic cell division
1) Stage 1 – The cell grows and copies its
organelles and chromosomes
2) Stage 2 – Chromatid Separation =
Mitosis
3) Stage 3 – Cell division into two cells
identical to the original cell
_________ = eukaryotic cell
division
• The process of _____________________
• Ensures that each cell receives a copy of
each chromosome.
• 4 phases
Mitosis
• D____________
• L____________
• S____________
• Do demo with hands.
Definitions
Homologous Chromosomes (Pairs) – similar
chromosomes which pair up during cell division.
(ie. Humans have 46 chromosomes which are
23 pairs)
Chromatid – After each chromosome is duplicated
the two copies are called chromatids
Centromere – the point at which the 2 chromatids
are held together
Prior to Mitosis
• The ______________________ are
copied
• At this stage each chromosome now
consists of 2 chromatids.
• Centrioles are copied
Mitosis Stage 1 (Prophase)
• The nuclear membrane breaks down
• Chromosomes condense into compact
structures
• Centrioles move to opposite sides of the
cell
• Fibers form between the two centrioloe
and connect to the centromeres of the
chromsomes
Mitosis Stage 2 (Metaphase)
• The chromosomes are lined up along the
equator (center of the cell)
Mitosis Stage 3 (Anaphase)
• The chromatids separate and are pulled to
opposite sides of the cell by the fibers
attached to the centrioles.
Mitosis Stage 4 (Telophase)
• Anuclear membrane forms around the now
2 sets of chromosomes.
• The chromosomes unwind
• The fibers disappear
After mitosis
• The ____________________ (cytokinesis)
• There are now 2 cells where there was
once one. They are identical to each
other.
Cytokinesis
• In animals – the membrane simply pinches
off
• In plants – a cell plate forms in the middle
of the dividing cell ad becomes the new
membrane that will separate the 2 cells.
2 Chromosomes
*Parent Cell
Doubles to 4 chromosomes
“DUPLICATE”
“LINEATE”
“SEPARATE” = cytokinesis
*Daughter Cells
http://www.cellsalive.com/mitosis.htm
Mini Quiz
1) What is Cell Division?
2) How do prokaryotic cells make more
cells (what is the process called)?
3) How do eukaryotic cells make more cells
(what is the process called)?
Cell Division (Mitosis)
•
Cell division allows an organism to :
1) _______________
2) _______________
3) _______________
– Prior to division the cells copies its DNA
– Cell Division is cellular reproduction
– The daughter cell has the ____________ of
chromosomes as the parent cell.
Interphase
This is how all
cells look
before
mitosis.
Please be
aware that
Interphase
is a phase
of the cell
cycle, but
NOT a
stage of
mitosis.
• Mitosis - Early Prophase To begin mitosis, the nuclear
membrane breaks down, while the chromosomes
shorten and thicken (here, a chromosome is two
chromatids, bound at a point called the centromere,
making an "X" shape). The other structures important for
mitosis are also forming (i.e. the centrioles).
•
Mitosis - Metaphase The mitotic
spindle apparatus has now
formed and lies on the poles of
the nucleus (but remember, the
nuclear membrane has broken
down, so there is no distinctly
delineated nucleus). The
chromosomes are lined up along
the cell's equator, also known as
the equatorial plate, and are
attached to the mitotic spindle
apparatus via microtubules (to
try and visualize the
microtubules extending from the
poles to the chromosomes on
the equator, think of the Earth it's as if rope was extending from
the chilly north and south poles
to the chromosomes basking in
the sun at the equator). Here's
the confusing part - When the
individual chromatids (½ of the
"X") are separated from the
chromosome (the "X"), they are
now each referred to as a
chromosome (i.e. In metaphase,
the chromosome, composed of
two chromatids, separates into
the individual chromatids, which
are then renamed
chromosomes, even though they
were only one half of a
chromosome only moments
before!) - Whew!
• Mitosis - Anaphase The newly formed chromosomes
(which were recently chromatids while they were still ½
of the "X") are pulled along the microtubules toward
opposite poles of the cell (like Monarch butterflies
migrating back to Canada and the southern tip of South
America (toward the poles) from Mexico (near the
equator).
•
•
Mitosis - Telophase
The chromosome
have finished their
migration to the
poles and the
mitotic structures
breakdown. The
plasma membrane
of the cell pinches
down along the
equator creating
two separate cells
(similar to twisting a
long balloon and
forcing it to pinch in
the middle). At this
time, the
chromosomes
become indistinct
(as they are during
Interphase), the
nuclear membrane
forms again and the
nucleolus
reappears.
Classification
Midterm Review
Lab Safety
• The number one rule is to Follow
directions
Measuring
• In Science we use the metric system
Length –measured in meters
Mass – the amount of matter in a substance
- measured in grams
- measured with a triple beam balance
Volume- the amount of space something occupies
- measured in cm3 (solids)
- measured in liters (liquids)
- measured with a graduated cylinder
Temperature - measured in Celsius
Scientific Method
•
1)
2)
3)
4)
5)
6)
Scientific Method – The orderly and
universally accepted steps that a scientist
uses to answer and solve problems.
Ask a question
Form a hypothesis
Test the hypothesis
Analyze the results
Draw Conclusions
Communicate the results
Scientific Method
1) Ask A Question – Good questions come
from good observations. Observations are
only useful if they are accurately made
and recorded.
– Tools to assist in observation
• Eyes, ears, noses, microscopes. Telescopes,
graduated cylinders, clocks, rulers, etc.
Scientific Method
2) Form a Hypothesis – “educated guess”
You must think logically and creatively
Can you have different hypotheses for the
same problem?
Scientific Method
3) Test the Hypothesis
a) Controlled Experiment – one variable
1) variable- the single factor that is different or
changed in an experiment
2) ‘If – Then’ statements
3) Collect the Data
4) Law of large numbers (number of tested groups
or the number of times an experiment is
repeated)
Control – the group that does not receive the
variable
Scientific Method
4) Analyze the Results
– organize the data
(tables, graphs)
100
80
60
40
20
0
East
West
North
1st 2nd 3rd
Qtr Qtr Qtr
4th
Qtr
Scientific Method
•
5) Draw Conclusions – Do the results of
the experiment support the hypothesis.
–
If Not? What have you accomplished? You
have proven and learned that the
hypothesis is wrong.
»
»
»
Options
Repeat
Find another explanation for what you have
observed
Scientific Method
6) Communicate the results – How?
You want to see if mice grow larger
when they eat swiss cheese.
•
•
•
•
Design an experiment to test this theory.
State the hypothesis
List the materials needed
What steps would you take.
Characteristics of Life
• Living things sense and respond to
change
• Living things reproduce
• Living things have DNA
• Living things use energy
• Living things grow and develop
Necessities of Life
•
•
•
•
Food
Air
Water
A place to live
Organization of Life
Cells
Tissues
Organs
Organ Systems
Organisms
Microscope
1) Made of 2 lenses which multiply
magnification
a) Ocular lens or eyepiece
b) Objective lens
Magnification = ocular mag. x objective mag.
Cell Theory
1) Cells are the basic unit of life
2) All living organisms are made of 1 or
more cells
3) All cells come from existing cells
Review Review
1) C
2) A
3) D
4) B
5) A
6) C
7) D
8) B
9) D
10) C
Measures mass
Measures liquid volume
Measures centimeters
Measures Celsius
Measures milliliters
Measures grams
Measures length
Measures temperature
Measures meters
Measures the amount of matter in a
substance
11) 3 ml
What is the volume in the
cylinder?
12) 2.6 cm What is the length of the
wooden block?
13) 4
Which group of measurements
contains only metric units?
14) 4
Which lab equipment is correctly
paired with a unit of measure?
15) C
The amount of matter in a substance?
16) A
The basic unit in the metric system
used to measure mass?
17) E
An instrument used to measure the
volume of a liquid is a(n)?
18) C
A substance in outer space will have
no?
19) E
The prefix “centi” means?
20) A
The amount of space a substance
takes up is called its?
21)9.2 cmThe earthworm is how many
centimeters long?
A) 0.5 cm
B) 5 cm
C) 5.5 cm
D) 6.5 cm
What are the masses?
22) 175.7 g
23) 622.9 g
24) 286.2 g
What volume is indicated on each graduated
cylinder?
25) 47 ml
26) 32 ml
27) 13 ml
What temperature is indicated on each
thermometer?
28) 68°C
29) -11°C
30) 11°C
31) Scientists use a system of measurement called
the metric system.
32) Length
2 cm
width
2.5 cm
height
2 cm
Volume
10 cm3
33) 25 ml What was the volume of the water
before adding the rock?
34) 30 ml What is the volume of the water and
the rock together?
35) How can you find out the volume of just the
rock?
Subtract (volume of water) from
(volume of water + the rock).
36) 5 ml converts to 5 cm3 What is the volume of
the rock?
Page 7-8
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
14)
15)
D A variable in the investigation
B Which group was the control group
C What hypothesis could be possible for this
experiment
B ( bad question)
A What set of conditions must be kept the same through the
whole experiment
E “We would like to find out which grow better”
E “ I think bean plants grow better with fertilizer than without”
D What sequence of steps is best
E The experimental group with normal conditions used for
comparison
B The single or one factor that is changed
B A way to test a hypothesis is to
C The first step in the scientific method
A ???
D
b
16) 2 Which was the control group?
17) Sterilized
What do we call anything boiled
for 10 min. to kill bacteria
18) D is the control and a,b,& c are the variable
groups
19) Iodine
20) Amount of iodine
21) D because it had no iodine
22) D the most and C the least
23) The greater the amount of iodine the lesser the
populations of bacteria.
Page 11-12 (matching)
1) Diffusion
2) Compound microscope
3) Chromosomes
4) Classification
5) Kingdoms
6) Magnification
7) Osmosis
8) Mitosis
9) Photosynthesis
10)Organic compounds
d
j
f
i
b
g
h
a
e
c
11) Hypothesis
12) Variable
13) Experiment
14) Control
15) Osmosis
16) Problem
17) Diffusion
18) Conclusion
19) Molecules
20) Information
i
d
g
h
b
j
e
c
a
f
21) 1) respond to stimulus
2) grow and develop
3) have DNA
4) reproduce
5) Use energy
6) have cells
22) 1) food
2) air
3) water
4) a place to live
23) Photosynthesis and cellular respiration
24) Consumption of food and cellular respiration
25) Cellular respiration
26) To build organelles and grow
27) slide, slip, specimen, water
28) Flip it and turn it upside down
29) Moves the opposite way
30) 1) position the specimen exactly in the center
of the field
2) focus in med. Power
3) refocus with fine focus
4) turn the objective lenses
31) 1) follow directions
2) goggles
3) clean up spills
4) never taste anything
5) don’t wear dangling clothes or open toed
shoes
Scientific Method Questions
1) Do irradiated radishes grow better
2) Irradiated radishes will grow larger than normal ones
3) Soil, light, water, control, experimental groups
4) Radiation
5a) normal radishes
5b) soil, light, water
6a) 1) hypothesis
2) experiment
a) control group
b) experimental group
c) collect data
3) analyze data
4) conclusion
5) communicate results
6b) height of the plants in each group
7) Taller plants from irradiated beans
Would prove it
Cells Section
1) Cell membrane
2) Nucleus
3) Chloroplasts or organelles
4) vacuole
5) cytoplasm
6) Cell wall
7) Cell membrane
8) Nucleus
9) Cytoplasm
10) vesicle
11) Other cells
12) For cellular activities and building blocks
13) Cell wall and chloroplast
14) Cell
15) 1 or more cells
16) Nucleus
17) Chloroplast
18) Cell membrane
19) Cell wall
20) Cytoplasm or cytosol
21) ER
22) Energy
23) Small enough to diffuse through the membrane
24) DNA structures
25) In the nucleus
26) Mitosis
27) Reproduction
28) a) Nucleus
b) Cytoplasm
c) cell membrane
29) Division
30) Reproduction and growth
31) Healing and replacement
32) Cells
33) Parent cell
34) Daughter cells
35) They are the same *****
36) Diffusion
37) Tissues – organs – organ systems - organisms