Transcript AP Biology Cells Unit 2_1

AP Biology
Cells
Monday, Sept. 23rd
 Learning Target: Students will recall their knowledge of cells
and understand why cells are small.
 Go Over Test.
 Brain Storm – Everything you remember about cells.
 Prep for lab on Wednesday – Part 1 Diffusion and Osmosis
Tuesday, Sept. 24th
 Learning Target: Students will understand the relationship
between cell volume, surface area, rates of diffusion and cell
efficiency
 Why are cells so small?
 Differences between the categories of cells.
 Compare and Contrast Different Types of Cells.
 Prep for Cell Surface to Volume Lab.
 Lab – Part 1
 Write up in Notebook
Cell Size
 In graph one as surface area…
volume …rate.
 In graph 2 as the length of the
side … the surface to volume
ratio …
 Based on the data table what
conclusions can you make about
surface area and volume.
.
Cells
All Cells
1.
2.
3.
4.
5.
Eukaryotic Cells
1.
2.
3.
4.
Animal Cells
1.
2.
3.
Prokaryotic Cells
1.
2.
3.
Plant Cells
1.
2.
3.
Terms:
Cytosol
Plasma Membrane
Chromosomes
Ribosomes
Nucleus
Cytoplasm
Nucleoid
Endoplasmic Reticulum
Cell Wall
Central Vacoule
Chloroplasts
Golgi Apparatus
Nucleolus
Mitochondria
Centrosome
Cytoskeleton
Wednesday, Sept. 25th
 Learning Target: Students will understand the relationship
between cell volume, surface area, rates of diffusion and cell
efficiency
 Complete: Surface Area to Volume Lab
 Lab – Part 1
 Write up in Notebook
 Due: Friday, Sept. 27th
 Students will investigate the relationship of among surface area, volume,
and the rate of diffusion by designing an experiment with the use of agar
gells.
 Table of Contents: Cell Size and Diffusion Rates
 Title
 Introduction: Brief statement of purpose, background knowledge of the concepts, and
hypothesis. (less the 100 words)
 Materials and Procedures: Brief explanation of what you will do and what you will
use.
 Results/ Data Collection and Analysis: Data Tables, Graph with title, X and Y
Labeled.
 Conclusions and Discussion: Results summarized, Errors identified, compare to
hypothesis, conclusions stated, suggestions for improvement
 Questions: What are questions for further investigation? What new questions arise?
Questions to Address
 Which surface area-to-volume ratio gave the fastest diffusion
rate?
 Which surface area-to-volume ratio had the greatest diffusion
depth?
 How might a cell’s shape influence the rate of diffusion?
 What factors affect the rate of diffusion and how can these be
tested?
Sample Data
Cell
Dimensions
Surface Area
Volume
Surface
Area to
Volume
Ratio
Rate of
diffusion
(Show
Calculations)
.
Percent of
Discoloration
after 10 min
Thursday Sept. 26th
 Learning Target: Students will understand the relationship of
cell size and diffusion rates. Students will be able explain the
endosymbiotic theory and the evidence for it.
 Go over Lab
 Endosymbiosis
Thought Questions…
 Why are prokaryotic cells so much smaller than eukaryotic
cells?
 Which type of cell was first on the planet? Why? What was
the order of cellular diversity?
 Which type of cell has been more successful in terms of
evolution, survival and populating the planet?
 How did we evolve from prokaryotic life into eukaryotic life?
 Define and draw your interpretation of the evolution from
prokaryotic life to eukaryotic life.
 Define the evidence we have for this process?
 What three main categories of life does it create?
 Pgs. Biology in Focus 484 - Red Book 529, 541
Endosymbiosis
What we know:
 Prokaryotic Life originates between 3.5 to 3.9 billion years
ago
 Chemiosmotic Mechanism of ATP Synthesis
 Use Molecular Hydrogen, Methane Hydrogen Sulfide for
energy
 VERY DIFFERENT BUT THE SAME
What we know:
 Prokaryotes evolve from chemiosmotic mechanisms to
photosynthesis
 Creates a Oxygen rich atmosphere.
 BAD and GOOD
Eukaryotic Life 2.7 BYA
 Cytoskeleton –
 Big Deal
 Evolutionary Advantages
to folding of membranes?
Figure 4.16
Endoplasmic
reticulum
Engulfing of oxygenusing nonphotosynthetic
prokaryote, which
becomes a mitochondrion
Nucleus
Nuclear
envelope
Ancestor of
eukaryotic cells
(host cell)
Mitochondrion
Nonphotosynthetic
eukaryote
At least
one cell
Engulfing of
photosynthetic
prokaryote
Chloroplast
Mitochondrion
Photosynthetic eukaryote
Endosymbiosis Evidence:
Mitochondria and Plastids (chloroplasts)

Enzymes and Transports systems same as modern prokaryotes
 Replicates by binary fission same as prokaryotes
 Contain their own DNA (Plasmids same as prokaryotes)
 Contain their own ribosomes to make their own proteins
Three Distinct Lineages…
 Domain Eukarya (Eukaryotic)
 Domain Bacteria (Prokaryotic) - Normal
 Domain Archea (Prokaryotic) – EXTREMOPHILES
 Thermophiles – TEMP.
 Halophiles – SALT
 Methanogens – USE Carbon Dioxide and Hydrogen gas to
make energy – creates methane gas – sewage treatment, guts
Friday, Sept. 27th
 Learning Target; Students will be able to identify and explain
the functions of the various structures that make up the
endomembrane system.
 Reading Check
 Turn in Lab Notebooks
 http://www.youtube.com/watch?v=yKW4F0Nu-UY
 Discussion: Endomembrane System
Write a Narration for the video.
 Must include the following structures with their functions.
 Typed
 Due: Tuesday
 Cytoskeleton, Cell membrane, plasma membrane, microtubules,
microfilaments, intermediate filaments, motor proteins, mitochondria,
nucleus, nuclear pores, nuclear envelopes, Endomembrane system,
Ribosomes, Golgi Apparatus, Cis face, Trans face, Vesicle, exocytosis,
Smooth ER, Rough ER, extracellular matrix, transport vesicles, motor
protein, glycoproteins, mitochondria, centrosomes.
Figure 4.15-1
Nucleus
Rough ER
Smooth ER
Plasma
membrane
Figure 4.15-2
Nucleus
Rough ER
Smooth ER
cis Golgi
trans Golgi
Plasma
membrane
Figure 4.15-3
Nucleus
Rough ER
Smooth ER
cis Golgi
trans Golgi
Plasma
membrane
Figure 4.13
Vesicle containing two
damaged organelles
1 m
Mitochondrion
fragment
Peroxisome
fragment
Lysosome
Peroxisome
Mitochondrion
Vesicle
Lysosomes: Autophagy
Digestion
 Compare and contrast the roles of smooth ER with rough
ER. What type of cells would expect to find the two
different types.
 A protein that functions in the ER but requires modification
in the Golgi apparatus before it caqn achieve function.
Describe the protein’s path through the cell, starting with the
mRNA molecule that specifies the protein.
 Compare and contrast mitochondria and chloroplasts with
regard to structure and function.
Tuesday, Oct. 1st
 Objective: Students will understand the basic structure and
function of the cytoskeleton, cell wall, extracellular matrix,
cellular junctions and the cell membrane.
 task card.
 Discussion Cell Membrane
Table 6.1 The Structure and Function of the Cytoskeleton
Write a Haiku poem that
describe the cytoskeleton.
Remember Haiku’s are 5, 7, 5
syllable poems.
Figure 6.28 Plant cell walls
Central
vacuole
of cell
Plasma
membrane
Secondary
cell wall
Primary
cell wall
Central
vacuole
of cell
Middle
Lamella
(Pectin)
1 µm
Plasmodesmata
Figure 6.29 Extracellular matrix (ECM) of an animal cell
Collagen fibers
Polysaccharide
molecule
EXTRACELLULAR FLUID
.
proteoglycan
Core
protein
Fibronectin
Plasma
membrane
Integrin
Carbohydrates
Integrins
Microfilaments
CYTOPLASM
Proteoglycan
molecule
Figure 6.31 Exploring Intercellular Junctions in Animal Tissues
TIGHT JUNCTIONS
Tight junction
Tight junctions prevent
fluid from moving
across a layer of cells
0.5 µm
At tight junctions, the membranes of
neighboring cells are very tightly pressed
against each other, bound together by
specific proteins (purple). Forming continuous seals around the cells, tight junctions
prevent leakage of extracellular fluid across
a layer of epithelial cells.
DESMOSOMES
Desmosomes (also called anchoring
junctions) function like rivets, fastening cells
together into strong sheets. Intermediate
filaments made of sturdy keratin proteins
anchor desmosomes in the cytoplasm.
Tight junctions
Intermediate
filaments
Desmosome
Gap
junctions
Space
between
cells
Plasma membranes
of adjacent cells
1 µm
Extracellular
matrix
Gap junction
0.1 µm
GAP JUNCTIONS
Gap junctions (also called communicating
junctions) provide cytoplasmic channels from
one cell to an adjacent cell. Gap junctions
consist of special membrane proteins that
surround a pore through which ions, sugars,
amino acids, and other small molecules may
pass. Gap junctions are necessary for communication between cells in many types of tissues,
including heart muscle and animal embryos.
 Compare different aspects of cell structure
 What structures best reveal evolutionary unity?
 Provide examples f diversity related to specialized
modifications.
 Recreate the diagram on your whiteboard label as much as you possibly
can with structure and function.
 Label the hydrophobic and hydrophilic regions.
 The term fluid mosaic model is often used to describe the cell membrane what
is meant by this term and list and what factors contribute to its fluidity? Be
specific to the role of cholesterol
 Describe three ways in which molecules can move across a cell membrane.
 Unsaturated Phospholipids
 Increase fluidity
 Cholesterol
 Temperature buffer
 Integral Proteins?
 What are the functions of membrane proteins?
Wednesday, Oct. 2nd
 Objective: Students will understand the fundamental
processes that drive movement across the cell membrane.
 Discussion
 Lab Prep.
 Active vs. Passive Transport (Concentration Gradient)
Passive Transport – No energy, High To Low Conc.
Diffusion
What types of molecules? Why?
Things that affect the rate of diffusion
 Why differentiate between simple diffusion and facilitated diffusion?
 What are the characteristics of the proteins? Why are they necessary?
Osmosis: Diffusion of Water (Aquaporins)
Hypotonic, Hypertonic, Isotonic
Osmosis
 What about plants and prokaryotic cells in fresh water
environments?
Cell Wall = Pressure
Water Potential = waters ability to move
 Always from high to low water potential.
 Pressure is positive (Increases waters ability to move)
 Solute Potential
 Always negative
 More solute water less likely to move
 Hypotonic (Cell Wall) = Water moves in until pressure builds up to
equalize water potential = cell doesn’t lyse.
Thursday, Oct. 3rd
 Learning Target: Students will understand how water moves
across cell membranes.
 Lab: Diffussion and Osmosis
 Potato Challenge – Water Potential – Potatoes cannot be left
over a weekend
 Formal Lab: Due Tues. Oct. 8th
Friday, Oct. 4th
 Learning Target: Students will understand how water moves
across cell membranes.
 Complete lab.
Monday Oct. 7th
 Learning Target: Students will understand how water moves
across cell membranes.
 Finish Lab Write Up.
Tuesday, Oct. 8th
 Objective: Students will be able to compare and contrast
active and passive transport.
 Lab Due
 Task Cards
 Discussion
 Proton Pump
 Cotransport
 Bulk Transport
 Endocytosis
 Exocytosis
 Sodium Potassium Pump
 Active Transport
 Electrochemical gradient
 Sodium Potassium Pump
 Active Transport
 Electrochemical gradient
Wednesday, Oct. 9th
 Objective: Students will understand the how cells
communicate.
 How doesSarin Gas Work
 Read: How Caffeine Works.
 Focus:
o What is going on in your brain in the absence of Sarin?
o What is going in your brain and body in the presence of Sarin?
 Group:
 Diagram the answer to both of the above questions.
 Discussion: How Cells communicate.
 The Signal Transduction Pathway
 http://www.youtube.com/watch?v=jjfYQMW_nek
Types of Cellular
Communication
Local Regulators
(Cell to Cell)
Growth Factors
Stimulate cell
growth
(animals – Paracrine)
Synaptic Signaling
Neurotransmitters
(between nerve
cells)
Long Distance
Signaling
Hormones
Endocrine
Signaling
Partner
 Identify the three stages of cell communication – the signal
transduction pathway.
Reception
 Ligand – Molecule that binds to another molecule, generally
a larger one.
Intracellular Receptors
 Receptors in Cytoplasm or
Nuclear membrane
 Must pass through the cell
membrane
 Small
 Non – polar molecules
(steroids)
 Sentence stem:
 The steroid… and…
which results in…
Three Types of Membrane Receptors
 G-Protein Linked Receptors
 Receptor Tyrosine Kinase
 Ligand Gated Ion Channel
G-Protein Linked Receptors
 The ligand… which… the cellular response.
Receptor Tyrosine Kinase
 The signal Molecule… which… The cellular response.
Ligand Gated Ion Channel
 The
neurotransmitter…
which causes…
Transduction Pathways
 Protein Kinases: Enzyme that transfers phosphate group
from ATP to a protein.
 Second Messengers
 Cyclic AMP
 Calcium
Phosphorylation Cascade
Phosphorylation Cascade
 A phosphorylation cascade is like a … because…
Second Messenger c-AMP
 Adenylyl Cyclase
 Phosphodiesterase
Second Messenger c-AMP
 Explain
Response
 Control
 Amplification
 Specificity of Cell Signaling
Response – Specificity of Cell Signaling
Friday, Oct. 11th
 Learning Target: Students will understand the purpose and
mechanism of cellular reproduction and its connection to
disease.
 Discussion
Questions For You!
 What is the purpose of
reproduction?
 Is all reproduction accomplished
the same way?
 What is the difference between asexual and sexual
reproduction?
Vocabulary Practice
 What is a genome?
 What is a chromosome? And What it is it made of?
 What is the difference between somatic cells and gametes?
 Why do somatic cells have chromosomes in pairs and gametes
don’t?
 If a cell is going to undergo asexual reproduction what must
happen to its chromosomes first?
 Why is there a purple and blue chromosome?
 Why is there to halves to each chromosome? What are they called?
 The circle in the middle is a ____________ and it…
Questions for you!
 Asexual reproduction requires cells to do what with their
genome?
 During asexual reproduction their genome is…
 This results in cells that are…
 Cell Cycle
 Interpret
 Group: Draw the phases of mitosis and describe each phase in
one sentence.
 What board and notebook
Monday, Oct. 14th
 Objective: Students will understand the overall purpose of
mitosis in cell division and the different phases of mitosis.
 Discussion: Purpose and Stages of Mitosis
 Lab: Counting Phases / Determining Time
 Prophase
 Chromosomes
 Mitotic Spindle
 Prometaphase / Metaphase
 Chromosomes
 Mitotic Spindle / Kinetochore
 Anaphase
 Chromosomes
 Microtubules
 Telophase
 Cytokinesis
Mitosis
1. Using on onion root tip identify cells in the different stages of the cell cycle.
2. Count at least two full fields of view. If you have not counted 200 cells, then count a third field of
view.
3. Calculate the estimated time spent in each phase. It takes24 hours (or 1,440 minutes) for onion roottip cells to complete the cell cycle.
Percent of cells in stage X 1,440 minutes = ___________ minutes of cell cycle spent in stage.
Questions:
4. Would the percentage of cells in mitosis be the same for all of the tissues in a plant?
5. Using the same basic techniques predict how cancerous cells would be different?
Percent of
Total Cells
Counted
Number of Cells
Field 1
Interphase
Prophase
Metaphase
Anaphase
Telophase
Total Cells Counted
Field 2
Field 3
Total
Time in Each Stage
Tuesday Oct. 15th
 Objective: Students will understand the control mechanisms
of the cell cycle.
 Discussion: Cell Cycle Control
 Test.
Check points and G0
 Control of the cell cycle is like a… because…
 The checkpoints represent… because…
 If a cell passes the G1 check point it will go on to divide.
 If not it stays in G0
How Check points work
 Players:
 CDK (Cyclin Dependent Kinases)
 Kinases – activate or inactivate
proteins by phosphorylating them.
 CDK – activity is dependent on
another protein cyclin.
 Cyclin – Proteins whose
concentration fluctuates throughout
the life of the cell.
 MPF – Maturation promoting factor
or mitosis promoting factor
Concentration of cyclin vs. MPF activity
 Starting at G1 cyclin concentration… and then…
 As cyclin concentration … MPF activity…
 Concentration of cyclin rises, activates MPF (CDK complex)
 Cell goes through mitosis – signal transduction pathway
G2 check point
 MPF activity is controlled by…
 MPF will stimulate the cell to go through mitosis (signal
transduction pathway)
Cancer cells
 Based on the G2 checkpoint hypothesize on two mutations that
might cause cancer.
Cancer cells
Tumor Suppressing
genes don’t activate
to degrade cyclin
Oncogene:
Mutation that
causes cyclin
concentration
to stay elevated
 Based on the G2 checkpoint hypothesize on
two mutations that might cause cancer.
Cancer Connection
 Test: Wednesday Oct. 16th and 21st
Mode of
Nutrition
Autotroph
Carbon – CO2
Photoauotroph
Energy – Light
Chemoautotroph
EnergyInorg. Compounds
Heterotroph
Carbon – Organic
Compounds
Photoheterotroph
Energy – Light
Chemoheterotroph
Energy –
Org.Comp.
Monday, Sept. 26th
 Objective: Students will Complete osmosis lab
 Lab: Diffusion and Osmosis.
 Potato:
 Diagram of your lab set up.
 Data table.
 Molarity of the potato – How did you determine it?
 Graph?!?!
Tuesday, Sept. 28th
 Objective: Students will be able to explain the data from
their lab.
 Collect Data – % differences on board – Class average.
 Explain the results from your potato lab.
 Discussion – The cell membrane.
Wednesday, Sept. 28th
 Objective: Students will understand the structure and
function of the cell membrane.
 Turn in Lab (One per group)
 Data Tables
 Graph
 Analysis Paragraph
 Task Card
 Discussion
Figure 6.20 The cytoskeleton
Microtubule
0.25 µm
Microfilaments
 Hypertonic Solution = More solute in solution; less solute in cell =
Higher water potential in cell
 Hypotonic Solution = Less solute in solution; more solute in cell =
Higher water potential outside of cell.
 Isotonic = All is even