WARM UP: Tues, Oct 1• In your 3 brad folder:

• Define homeostasis in your own words.

(Hint: look in cell theory notes)

Cellular ProcessesDay 1

Objectives

1. Define homeostasis.2. Describe the Fluid Mosaic Model.3. List items that enter & exit the cell .

Homeostasis

= ability to maintain internal equilibrium– Maintain = keep– Internal = inside– Equilibrium = stable or balanced

Why is maintaining homeostasis in our body & cells important?

An imbalance = disease or death!

Cell Membrane• Function: 1) Regulates what enters & exits cell

2) Provides protection & support

Cell Membrane AKAs• AKA: Plasma Membrane• AKA: Phospholipid Bilayer• AKA: Fluid Mosaic Model

Fluid Mosaic Model• Fluid = not solid, membrane moves• Mosaic = made of many parts

Parts of a Plasma Membrane• Different Macromolecules in membrane:

1) Lipids = create bi-layer2) Protein = create channel to pass large items3) Carbohydrate Chains = identifying markers

A Closer Look at the Cell Membrane

Phosphate head

Fatty Tails

Lipid Bi-Layer = 2 layers

Phospholipid Bilayer

Latin Root: Bi = 2

• Phospholipid = hydrophilic head + hydrophobic tail BILAYER

• Hydrophilic = water loving• Hydrophobic = water fearing• Water & Oil do not mix

What Enters?

• What the cell needs for survival1) Nutrients2) Water3) Oxygen 4) Nucleic Acids (blueprint)

What Exits?• What the cell needs to remove for survival

(wastes)1) Carbon Dioxide2) Excess water 3) Urea 4) Other cellular wastes

Membranes1) Permeable = anything can cross

2) Impermeable = nothing can cross 3) Selectively Permeable = some substances can cross, but not others

AKA Semipermeable

***Most membranes are selective***

Phospholipid Bilayer and maintaining homeostasis

• Keep Balance = membrane selectively permeable

NO ENTRYENTER

Egg Lab: Day 11. Paste chart onto spare

sheet of notebook paper you picked up at the door

2. Write your name, date, and period at top right corner of

notebook paper3. Hypothesis: I believe the

egg shell will _______ with vinegar.

Egg Lab: Day 2

Answer questions 1-2 in complete sentence

Hypothesis Day 2: “ I believe…”- Will the syrup level go up or down?- Will the egg get larger or smaller?

WARM UP: Wed, Oct 2• In your 3 brad folder:

• What is the difference between a permeable and impermeable membrane?

Cellular ProcessesDay 2

Objectives

1. Define diffusion & osmosis.2. Explain the 3 types of osmosis.3. Define osmotic pressure.4. Predict the results of an osmotic lab

experiment.

How “things” get selected to come into and out of the cell…

DIFFUSION OSMOSIS

PASSIVE TRANSPORT

DIFFUSION= movement of particles from high to low

- Goes w/ the crowd - w/ the concentration gradient

• Does NOT require energy • Diffusion stops when 2

areas are EQUAL (homeostasis)

Low High

Facilitated Diffusion = movement larger molecules w/ “help” from protein channels• Does NOT require energy

OSMOSIS = diffusion (movement) of water

- From high to low- W/ the crowd- Does NOT require energy

Solvent & Solute

• Solvent = the liquid portion– i.e. the water in a salt water

mixture• Solute = the part that is

mixed in– i.e. the salt in a salt water

mixture

3 Types of Osmosis1) Hypertonic Solution = > (greater)

concentration of solute outside the cell than inside

- Cell Shrink

Latin root: Hyper = over, more, higher

3 Types of Osmosis 2) Hypotonic Solution = < (lower)

concentration of solute outside the cell than inside

- Cell Burst

Latin root: Hypo = under, less, lower

3 Types of Osmosis 3) Isotonic Solution = concentration solute

outside = concentration inside- Cell stays the same

Osmotic Pressure

= pressure exerted on a cell membrane due to concentration gradient

= different conc. on either side of the cell membrane

Egg Lab: Day 2

Answer questions 1-2 in complete sentence

Hypothesis Day 2: “ I believe…”- Will the syrup level go up or down?- Will the egg get larger or smaller?

Egg Lab: Day 3

Answer questions 3-7 in complete sentences

Hypothesis Day 3: “I believe…”- Will the water level go up or down?- Will the egg get larger or smaller?

WARM UP: Thurs, Oct 3• In your 3 brad folder:

• What is the difference between a hypertonic solution & a hypotonic solution?

Cellular ProcessesDay 3

Objectives 1. Define active transport.2. List the types of active transport.3. Define concentration.4. Predict the results of an osmotic lab

experiment.

Osmotic Pressure

= pressure exerted on a cell membrane due to concentration gradient

= different conc. on either side of the cell membrane

Active Transport= movement of molecules against the

concentration gradient***Low to High***

– Against the crowd– REQUIRES energy– ATP = energy in cell ATPRequiresEnergy

Endosytosis= take materials into cellLatin root: endo = inner

Endosytosis• Type 1:

Phagosytosis= engulf and ingest

particles= “cell eating”- EX: white blood

cells eating invading bacteria cells

• Type 2: Pinocytosis= ingest extracellular

fluid & its contents= “cell drinking”– EX: human egg cells

drinking nutrients from surrounding cells while maturing in ovary

Endosytosis

Exosytosis= cell releases materials to the outside

- discharge as membrane-bounded vesicles - pass through the cell membrane

= “out of the cell”

Latin root: Ex = outer, away from

Egg Lab: Day 3

Answer questions 3-7 in complete sentences

Hypothesis Day 3: “I believe…”- Will the water level go up or down?- Will the egg get larger or smaller?

WARM UP: Fri, Oct 4• In your 3 brad folder:

• Define the term equilibrium

Egg Lab: Day 4

- Answer questions 8-12 in complete sentences

Friday, Oct 4

• Periods 1, 2, & 5 = Cell Process worksheets

WARM UP: Mon, Oct 7• In your 3 brad folder:

• What are the 3 macromolecules found in the plasma membrane?

WARM UP: Wed, Oct 9• In your 3 brad folder:What type of active transport is shown in this diagram?

Cellular ProcessesDay 4

Objectives

1. Describe the difference between positive (+) and negative (-) feedback.

2. Define solution & concentration 3. Define concentration gradient.

Solution & Concentration

Solution = mixture 2+ substancesConcentration = amount of substance

(solute) in liquid (solvent)

– Cytoplasm = one concentration– Outside of cell = another concentration*** Want balance (homeostasis)***

Concentration • Concentration gradient = unequal

distribution on either side of a membrane

• Equilibrium = concentration same on both sides of cell

Feedback Mechanism = loop system in which system responds in

either: 1) same direction (positive feedback) 2) opposite direction (negative

feedback)

Feedback Mechanism

Feedback Mechanisms • Channels = allows larger particles to

come in. (Gate/Door)• Receptors = signal (Intercom) • Markers = identify the type of cell (ID Badge)

Positive Feedback = results in amplification or growth of output

signal

• Ex: If you eat a McDouble at McDonalds, a hormone is released to your brain to signal satiation. You will feel the same “happiness” each time you eat the hamburger.

Negative Feedback = results in system responding in the

opposite direction• EX: Regulation of blood glucose levels.

– Blood glucose levels continue to rise – May result in diabetes

• EX: Sweating

Egg Lab: Day 4

- Answer questions 8-12 in complete sentences

Feedback Research 1. Using a laptop, research an example of positive or

negative feedback. 2. Use the next blank page in your spiral to write a 6-8

sentence summary of the article you found. Be sure to write if it is a POSITIVE or NEGATIVE feedback.

3. Write the website that you found your information from at the bottom of your page.

4. This will be worth 4 stamps.

Login: first 5 letters of last name; first 3 letters of first name; 000 ( try 001 if you have the same name as someone else in the school) Password: student ID #

Avid Thinking Strategy • Map News! Page 9 #19 

Title of News Article or Topic

How does thisAffect me? Name of

SourceDate

Science Fact

ConclusionCluesEvidence

New Vocabulary

Branch ofScience

WARM UP: Tues, Oct 8• In your 3 brad folder:1) List two types of passive

transport. 2) Is the movement from high to

low or low to high w/ passive transport?

Tues, Oct 8

Latin Roots Quiz& Osmosis/Diffusion

Worksheets

Latin Roots Quiz

1. Bi = ______ 6. Macro = _____

2. Mono = _____ 7. Endo = ______3. Bio = ______ 8. Hypo = ______4. Poly = ______ 9. Hyper = _____5. Di = ________ 10. Ex = _______

Bonus: Cyto = ______

WARM UP: Wed, Oct 9• In your 3 brad folder:What type of active transport is shown in this diagram?

Wed, Oct 9

Stations Review

WARM UP: Thurs, Oct 10• In your 3 brad folder:• What process is shown in the

diagram?

Thurs, Oct 10

Gems of Wisdom

WARM UP: Fri, Oct 11• In your 3 brad folder:• Define the term positive

feedback and give an example.

Fri, Oct 11

Test

Alternate Assignment for Field Trip

1. Research a saltmarsh & wetlands habitat. 2. Look up the Galveston Bay Foundation & their Hip to Habitat program.3. Write a 2 page essay on how GBF helps preserve/restore saltmarsh habitat in our area.