cellular structure and function unit 3; chapter...

Name: _______________________________________________

Cellular Structure and Function

Unit 3; Chapter 7 Date Classwork Homework

Notes: History of Cells Read/Questions Chapter 7.1 and 7.2 Venn Diagram

Origins of Eukaryotic Cells Finish Origins Reading/Questions

Notes: Membranes Membrane Lab

Read/Questions Chapter 7.3

Notes: Organelles Color/label Cell Diagrams Cell Flip Book, Day 1 Cell Flip Book, Day 2 Finish Cell Flip Book Cell Lab – Comparing Plant and Animal Cells Finish Cell Lab Cell City Analogy

Review Sheet Finish Review Sheet (page 31)

Notes: Transport Gummi Bear Lab, Day 1

Read/Questions 7.4

Gummi Bear Lab, Day 2 Notes: Transport (finish) Osmotic Solutions Worksheet

Finish Osmotic Solutions Worksheet

Gummi Bear Lab, Day 3 Endocytosis Lab

Finish lab questions

Work on Potato Lab Study for Test Finish Potato lab

Test Review Finish Lab questions Complete packet and study

Test Prepare for next unit

Rubric:

Out of Your Score Reading Questions 40 PowerPoint Notes 20 Venn Diagram 10 Origins of Eukaryotic Cells

10

Membrane Lab 20 Flip Book TBA Comparing Lab 20 Osmotic Solutions 10 Gummy Bear Lab 20 Endocytosis Lab 10 Potato Lab 20

Total

Reading Questions 7.1

Before You Read:

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2.

3.

4.

5.

7.2

Before You Read:

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2.

3.

4.

5.

7.3

Before You Read:

1.

2.

3.

4.

5.

6.

7.

7.4

Before You Read:

1.

2.

3.

4.

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What did Robert Hooke call the boxes that he observed in cork?

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Why should I care?

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So, what is a cell?

Smallest _____________________ that can

support life

A bacterium is ________________ self-

sustaining cell

You are made up of trillions of

_____________________cells

Too small to see without a microscope

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Problem?

Miss Apgar wants to view a bacterial cell that needs to be magnified 1000 times in order to see it. Her compound light microscope has a 10X ocular lens. Which objective lens should she use to see the bacterium?_____________

Where is the ocular lens?____________________

Where is the objective lens? _________________

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What do we remember about microscope history?

Robert Hooke

Named the cell

Cell – Structural and

functional unit of life

Made sketches of the

microscopic world

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Anton van Leeuwenhoek

Perfected a single lens microscope

Examined _____________________ and

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Called creatures he saw “cavorting wee beasties”

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Some More History

Matthias Schleiden Studied plants Determined that all

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Theodor Schwann Studied animals Determined that all

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Some More History

Rudolf Virchow

German physician

Proposed that cells ______________________

to form new cells

Used his theory to diagnose patients

Father of pathology

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Cell Theory - putting their work together

All organisms are made of cells __________________________________________________________

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The cell is the basic unit of organization in living organisms __________________________________________________________

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All cells come from pre-existing cells __________________________________________________________

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How do we know that cells come from other cells?

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Two types of cells…

Prokaryotic cells

Simple interior

Considered to be the

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Eukaryotic cells

Complex interior

Considered to be the

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Prokaryotes

Simple interior

DNA in central ___________________________

region

Cellular _______________________ happen in open

space

Single cell organisms

Bacteria

Archaea

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Inside a Prokaryote

The _____________________ is where cell life takes place

DNA is concentrated in the nucleoid region

Ribosomes make proteins

The Flagellum provides _____________________

Capsule, cell wall, and cytoplasmic membrane provide __________________________________________

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Eukaryotes Complex interior

DNA is neatly packaged and protected by _________________________

___________________________________ perform cellular functions

Single and multiple cell organisms

Amoebas – single celled

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4 Kingdoms Animalia

Ex:_______________________________________ Plantae

Ex:_______________________________________ Fungi

Ex:_______________________________________ Protista

Ex:_______________________________________

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Inside a Eukaryote

The ______________________ is where the organelles are located

DNA is housed in the __________________________

Ribosomes make proteins

There are many other organelles each covered by a __________________________

Each organelle has its own function

__________________________ provides protection

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More on the Eukaryote cell

Important terminology

DNA –

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Organelle – _________________________________________

that carry out

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Means “little organ”

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First up: the plasma membrane

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The Cell Membrane

The cell membrane is selectively permeable

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Cell membranes are made from a

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Phospholipid Bilayer Structure

Each phospholipid has a ________________________

head and two ____________________________ tails

Polar head is attracted to water

Nonpolar tails are repelled by water

Outsideof cell

Insideof cell(cytoplasm)

Cellmembrane

Proteins

Proteinchannel Lipid bilayer

Carbohydratechains

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Phospholipid Bilayer Function

Allows some things in and not others

Polar molecules do not ___________________pass

H2O is an exception because it is small

Keeps the outside ___________________ and the inside __________

The plasma membrane is always in motion

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Fluid Mosaic Model

Fluid

Membrane is ____________________________________

Membrane is ____________________________________

Mosaic

There are molecules ___________________________________

in the bilayer

The _______________________________________________

looks like a mosaic

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Animal Cells vs. Plant Cells

Eukaryotic cell which makes up tissues in animals

Lack ______________ and _______________, and have smaller vacuoles.

Appears to be __________________because of the lack of a rigid cell wall.

Eukaryotic cell that makes up plants

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Animal Cell

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Plant Cell

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Cell Wall

Mesh of __________________________that

surrounds the

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Protects and supports the cell

Made of carbohydrate -

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Cytoplasm

Semi-fluid material inside the plasma membrane

Consists of _______________________and the

cellular organelles (all organelles except the

_________________________________________)

Cytosol - __________________________________

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_____________________________

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Cytoskeleton

Network of long, thin protein fibers provide an

____________________ for organelles

_____________________________- long hollow cylinders

that assist in

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within the cell

______________________________- thin threads that give

the cell shape and enable the cell to

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Nucleus

Contains genetic material (DNA)

Nuclear envelope

Nuclear pores allow ___________________________________

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in center

Very dense center

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Ribosomes

Produce ___________________________________

Made of RNA and protein

Made in the ________________________________

Some _________________________in the cytoplasm

Others ________________________ to endoplasmic

reticulum

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Endoplasmic Reticulum

Interconnected network of tubules

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Two types of Endoplasmic Reticulum

Rough ER Smooth ER

Where

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attach and make proteins

Appear to create bumps

and rough areas on the

membrane

No ribosomes

Produces complex

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and

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Golgi Apparatus

Modifies, sorts, and packs

proteins in sacs called

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Vesicles fuse with plasma

membrane

They release proteins which

move through membrane to

get outside of the cell

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Vacuoles

_____________________storage for materials in the cytoplasm

Store, transport, or digest food and waste

Plant cells – 1 large vacuole Animal cells – several little

vacuoles

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Lysosomes

Vesicles that contain

____________________________________________

to digest excess or worn-out organelles and food particles

They also digest bacteria and viruses that enter the cell

They are _____________________________________

in the Golgi apparatus.

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Centrioles

Made of Microtubules

Found near nucleus

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only

Assembled right before replication

Aid in cell ____________________

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Mitochondria Powerhouse Converts organic materials into ____________________ ATP

Outer and inner membranes with lots of folds

Provides large surface area to break

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(produce energy)

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Chloroplasts- Plant only

Capture

______________________

and convert it to

______________________

through photosynthesis

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Photosynthetic Animals

2010 - found an animal that makes proteins essential

for photosynthesis

Elysia chlorotica – sea slug that looks like a giant swimming leaf

Stole _____________________________________from algae it eats

can live up to 9 months without eating

Appears __________________________because of stolen chlorophyll

Lives - Eastern coast of the United States and Canada

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Cilia and Flagella

Cilia- _______________________, hair-like projections Move back and forth like oars on a rowboat Move substances along surface of the cell

Flagella- rather ________________hair-like projections Whip-like motion

Both are composed of microtubules _________________ cells through

watery environment

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Cell Transport

Passive Transport Active Transport

Does not use energy Goes

_____________________ the concentration gradient

3 types diffusion facilitated diffusion osmosis

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Goes ___________________ the concentration gradient Endocytosis Exocytosis

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Cell Transport

Diffusion -net movement of particles from

________________concentration to

_________________concentration

Doesn’t require energy because the particle are in motion

passive transport

Dynamic equilibrium- the overall concentration does

not change, but molecules are still

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What affects the rate of diffusion?

What makes molecules move faster? High _________________________________ High _________________________________ High _________________________________

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Facilitated Diffusion

Some ions and molecules can’t ____________________ across the cell membrane

Facilitated diffusion – uses ___________________________________________to help move some molecules across the plasma membrane

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Osmosis

Osmosis – diffusion of ___________________ Most cells undergo osmosis because they are

surrounded by water

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Hyper—Hypo– Iso tonic Solutions These are comparing words Hypertonic -____________________________________ Hypotonic- _____________________________________ Isotonic- _______________________________________

What would happen if you Put a red blood cell in a hypertonic solution? Put a red blood cell in a hypotonic solution? Put a red blood cell in an isotonic solution?

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What happens to a red blood cell when…?

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Active Transport

Goes from ____________ to __________________ concentration

Requires Energy ATP

Moves __________________________________________

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Endocytosis

Endocytosis- moving large substances into the cell

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Exocytosis

Exocytosis- moving large substances out of the cell

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Comparing Prokaryotic and Eukaryotic Cells

Prokaryotic Cells Eukaryotic Cells

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Reading Questions:

1. Who proposed the endosymbiont hypothesis?

2. Billions of years ago chloroplasts and mitochondria were ____________________

_____________________________________________________.

3. What is symbiosis? Give a detailed description.

4. What does the prefix endo- mean?

5. Explain what an endosymbiont is.

6. What is a common example of an endosymbiont?

7. Explain in detail the beneficial relationship between hydra and algae. (Must be 3 or more sentences)

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8. What evidence suggests that algae are beneficial to the hydra?

9. How do the mollusks harvest the energy from the algae?

10. What is the benefit to the mollusk with the algae compared to mollusks without algae?

11. What happens when the chloroplasts in the mollusk stop functioning?

12. How does this relate to the endosymbiont theory?

When you are finished work on your homework reading and questions

27

Cell Membrane Lab Problem: Is the cell membrane a selective barrier?

Hypothesis:

Materials:

• Microscope • Microscope slides and cover slips • Yeast • Methylene blue stain (Be careful!!) • Water

• Heated water • Eye droppers/pipettes • 2 - 500mL beakers • Stirring rods

Procedure:

1. Done for you: Place a packet of dry active yeast in a beaker. Add 400mL of water and stir. a. One per class.

2. Done for you: Boil 400mL of water and one packet of yeast for 10 minutes and let cool. a. One per class.

3. Prepare a slide of the yeast in the warm water: a. Place a drop of the solution on a clean slide. b. Place a drop of Methylene blue onto the drop of yeast solution. c. Carefully cover it with your cover slip, remembering to drop it at an angle.

4. Look at the slide under the microscope, remembering to start focusing with low power first. 5. Find a good example of the yeast under high power and draw what you see in the data section below. 6. Repeat steps 3-5 for the yeast that has been boiled.

Data:

___________x ___________x Yeast Cells in Warm Water Boiled Yeast Water Mixture Conclusion:

1. Explain how boiling affected the yeast cells.

2. Why does the color of the two groups of cells differ? (remember to consider the role of the plasma membrane)

3. Are the plasma membranes selective barriers? Explain your answer.

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Cell Flip Book Assignment Your task is to create a cell flip book that you can use to study for this chapter. This is an INDIVIDUAL assignment. You must include all of the organelles listed below and the following for each organelle:

• Colored hand drawing • Organelle function • Where it is found (Prokaryotes: Bacteria and Archaea, Eukaryotes: Plantae, Animalia, Fungi, and

Protista)

Organelles:

1. Cell Membrane 2. Cell Wall 3. Nucleus 4. Nucleolus 5. Cytoplasm 6. Ribosome 7. Smooth Endoplasmic Reticulum 8. Rough Endoplasmic Reticulum

9. Golgi body 10. Chloroplast 11. Mitochondria 12. Centriole 13. Lysosome 14. Peroxisome 15. Vacuole 16. Cilia/Flagella

Rubric

Organelle Drawing Function Where Found Good (1) Poor (0) Good (1) Poor (0) All (1) Missing (0)

Cell Membrane Cell Wall Nucleus Nucleolus Cytoplasm Ribosome SER RER Golgi Body Chloroplast Mitochondria Centriole Lysosome Peroxisome Vacuole Cilia/flagella

Total Points: ___________ (out of 48)

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Color and Label the Plant Cell

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Color and Label the Animal Cell

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Color and Label the Bacteria (Prokaryotic) Cell

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Lab Comparing Plant and Animal Cells

Objective

In this investigation, you will compare the structure of a typical plant cell (elodea) and a typical animal cell (human).

Materials:

• Elodea leaf • Microscope slide • Toothpick • Compound Light Microscope • Methylene blue (be careful!!)

Procedure Part A: Examining Plant Cells

1. Place a drop of water in the center of a clean microscope slide.

2. Remove a leaf from the elodea plant and place it on the drop of water on the slide

a. Make sure the leaf is flat, if it is folded unfold it 3. Carefully place a coverslip over the elodea 4. LOW POWER- locate the leaf 5. Switch to medium or high power objective lens. 6. Observe the cells of the Elodea leaf. Draw and label what

you see

Part B: Examining Animal Cells

1. Place a drop of methylene blue on your slide a. The less the better.

2. Gently rub a clean toothpick along the inside of your cheek. 3. Rub the same toothpick on the methylene blue. 4. Carefully place a coverslip over the cheek cells 5. LOW POWER- locate the cells 6. Switch to medium or high power objective lens. 7. Observe the cells of the cheek cell. Draw and label what you

see

_________x

_________x

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Observations

1. What is the shape of an elodea cell?

2. What is the general location of the nucleus in an elodea cell?

3. What is the shape of a human skin cell?

4. What is the general location of the nucleus in a human skin cell?

5. How are plant and animal cells similar in structure?

6. How are plant and animal cells different in structure?

7. Explain why you cannot use an oak leaf in this investigation?

8. In general, the surface of a tree has a harder feel than the surface of a dog. What characteristics of each organism can be used to explain the difference?

9. If you were given a slide containing cells of an unknown organism, how would you identify the cells as either plant or animal?

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Cell City Analogy In a faraway city called Grant City, the main export and production product is the steel widget. Everyone in the town has something to do with the steel widget making and the entire town is designed to build and export widgets. The town hall has the instructions for widget making; widgets come in all shapes and sizes and any citizen of Grant can get the instructions and begin making their own widgets. Widgets are generally produced in small shops around the city; theses small shops can be built by the carpenters’ union (whose headquarters are in the town hall).

After the widget is constructed, they are placed on special carts which can deliver the widget anywhere in the city. In order for a widget to be exported the carts take the widget to the postal office, where the widgets are packaged and labeled for export. Sometimes widgets don’t turn out right and the “rejects” are sent to the scrap yard where they are broken down for parts or destroyed altogether. The town powers the widget shops and carts from a hydraulic dam that is in the city. The entire city is enclosed by a large wooden fence, only the postal trucks (and citizens with proper passports) are allowed outside the city.

Match the parts of the city (underlined) with the parts of the cell.

Organelle City Analogy

Mitochondria

Ribosomes

Nucleus

Endoplasmic reticulum

Golgi apparatus

Protein

Cell membrane

Lysosomes

Nucleolus

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Cell Organelle Review Sheet

Fill in Check Boxes Part of the Cell Structure Function Bacteria Plant Animal

Cell Membrane

Cell Wall

Nucleus

Nuclear Membrane

Nucleolus

DNA

Cytoplasm

RER/SER

Ribosomes

Golgi Apparatus

Mitochondria

Chloroplast

Vacuole

Lysosome

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Flow Chart – Identify organelles found in each

All Organisms

Domain Prokayote

Bacteria

Domain Eukaryote

Animalia Plantae Fungi Protista

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Osmotic Solution

1. Osmotic Solution: __________________________

Direction of the Movement of Water __________________________

What will happen to the cell? __________________________










RBC

100% H2O

RBC

40% H2O

RBC

80% H2O

RBC

85% H2O

Note: A RBC is 85% H2O and15% Solutes.

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RBC

90% H2O

RBC

75% H2O

90% H2O

80% H2O

70% H2O

70% H2O

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For 10-12: = water molecule

10.

Osmotic Solution: __________________________



11.




12.




30% H2O

40% H2O

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Gummi Bear Osmosis

Background Information:

Molecules are in constant motion, and tend to move from areas of higher concentrations to lesser concentrations. Diffusion is defined as the movement of molecules from an area of high concentration to an area of low concentration. The diffusion of water molecules through a selectively permeable membrane is known as OSMOSIS; water molecules move from an area of high concentration to an area of low concentration.

Question: How will soaking Gummy Bear candies in distilled water affect the size of the candy? Hypothesis: Materials:

• Plastic cup • Tap water • Saturated salt solution

• 1 Gummy bear • Ruler • Permanent marker

• Balance • 1 aluminum screen

Procedure:

Day 1: 1. Label your plastic with your names and mods, using the permanent marker. 2. Find the mass of your bear using the balance and record your data. 3. Use the ruler to measure your bear top to bottom (length), side to side (width) and front to

back. Calculate volume (L x W x H) and record your data. 4. Fill your plastic cup ½ way full with tap water. 5. Put your candy bear in the water. 6. Set the cup aside for one day.

Day 2

1. After the candy bear has been in the tap water overnight, pour the water with your gummi bear over an aluminum screen into the sink. Be very careful because the candy is now extremely breakable.

2. Blot the screen dry by placing it on a paper towel. 3. While the bear is on the screen, measure your bear top to bottom (length), side to side (width)

and front to back. Calculate volume (L x W x H) and record your data. 4. Find the mass of the bear. Do this by placing the entire screen with the bear on the balance.

Record the total mass. Then carefully slide the bear back into the empty cup. a. Find the mass of the screen alone and calculate the mass of the bear. Record your data.

5. Cover the bears with the saturated salt solution. Set aside overnight.

Day 3

1. Find the mass and dimensions of the bear using the same procedure as noted on Day 2. 2. Record all data. Calculate volumes.

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Data: Data Table for Mass

Mass (g) Before Soaking (Day 1)

After Tap Water (Day 2)

After Salt Water (Day 3)

Mass of screen and gummi bear

Mass of screen

Mass of gummi bear

Data Table for Volume

Dimensions Before Soaking (Day 1)

After Tap Water (Day 2)

After Salt Water (Day 3)

Length (cm)

Width (cm)

Depth (cm)

Volume (cm3)

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Questions & Analysis: 1. What happened to the candy after soaking in tap water overnight? Why?

2. Do you think you would get different results if you used distilled water instead of tap water? (Distilled water has fewer solutes than tap water).

3. What happened to the candy after soaking it in salt water overnight? Why?

4. What do you think would have happened to the bears if, after the last day, they were placed again in tap water?

5. Calculate the percent change in volume after each step of the experiment. a. % change in volume = (final volume – initial volume) / initial volume x 100 b. Record calculates below

% Change in Water % Change in Salt Water

Bear 1

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Endocytosis Lab Objective: Using the materials available you will demonstrate how a cell performs a type of endocytosis.

Materials:

• Paper bag • String

• One piece of candy • Scissors

Procedure: The paper bag represents your cell membrane. The air inside the bag is the cytoplasm. Your cell needs to “eat” a large molecule, like a protein or starch. You, working as an extension of your paper bag cell, need to get the large molecule (your candy) into the cell without exposing the inside of your cell to the outside air.

You may not put the molecule in through the bag opening. You MAY put your hand into the cytoplasm through the top of the bag to help with the procedure.

Analysis:

1. What organelle did you create in your paper bag cell during endocytosis?

2. Describe the difference between endocytosis and exocytosis.

3. Draw a detailed, labeled sketch of the process you used to show endocytosis in this lab. You should include a least three steps/stages and explain what is happening in each. Be sure to label the parts of the cell/bag involved

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Potato Lab Objective:

• Understand Diffusion and Osmosis • Be able to determine the solute concentration of a potato

Part A: Diffusion of Iodine and Starch

1. Obtain a 30cm piece of dialysis tubing, tie one end off 2. Add 15ml of Starch solution to the tubing and tie the other end off 3. Fill a 250mL beaker 2/3rd full of tap water. 4. Add 4 mL of Lugol’s solution to the beaker 5. Allow to sit for 30 minutes

1. What does iodine test for? ____________________________________________________________

2. Which substances are entering the bag? Which substances are leaving the bag? How do you know this?

_______________________________________________________________________________________

_______________________________________________________________________________________

____________________________________________________________

3. Based on your observations rank the following by relative size, beginning with the smallest: Iodine (IKI),

starch, Water (H2O)

______________________________________________________________________________

Initial Contents

Solution Color Initial Final

Bag Starch Water

Beaker Water Iodine

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Part B: Determine the Molarity of a Potato

Materials:

• 50mL Water • 50mL 0.2M sucrose • 50mL 0.4 M sucrose • 50mL 0.6M sucrose

• 50mL 0.8M sucrose • 5 small plastic cups • Plastic wrap

Procedure:

1. Pour 50mL of each solution in a small plastic cup 2. Use a Number 2 cork borer to cut 3 potato cylinders into 3cm sections. Remove all of the skin 3. Determine the mass of the three cylinders and record the mass in table 1.2 4. Put the 3 cylinders in the cup with water, cover with plastic wrap and let stand overnight. 5. Repeat procedure 2-4 for each remaining cup (0.2M, 0.4M, 0.6M, and 0.8M) 6. Remove the cores from the beaker, blot them gently on a paper towel, and determine their total

mass. 7. Record the final mass in the table below. 8. Graph your data on graph on the next page.

Data:

Contents in Beaker Initial Mass Final Mass Mass Difference

(initial mass – final mass)

Percent change in mass (mass difference/initial mass)X

100 0.0 M Water

0.2 M sucrose

0.4 M sucrose

0.6 M sucrose

0.8 M sucrose

Lab Station #7

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9. Determine the molar concentration of the potato core. This would be the sucrose molarity in which the mass of the potato core does not change. To find this, add a line of best fit to your graph. Then, the point at which your line crosses 0% change.

Molar concentration of sucrose __________________M.

10. Your friend asks you to determine the molar concentration of Gatorade. Design an experiment to test this.

cellular structure and function unit 3; chapter...

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