Cell theory power point 2

ZOOLOGY!!!! 3…2..1.HERE WE GO!

What we will be learning in this Unit • Basic Scientific concepts

o Theory vs law o Scientific m ethod o Scientific term inology

• Cells: o Cell theory o Cell organelles o Cellular mem branes

ß Types of transport o Types of cells o The origin of cells o Cellular respiration

• Basic Taxonomy o Kingdom names and characteristics o Order of taxonomy

o Basic classification

My hypothesis: expect a test in 3-4 weeks

Common Scientific Laws and Theories:

What we will be focusing on today:

Scientific MethodTheory Vs. Law

SC.912.L.14.2: Describe the scientific theory of cells (cell theory and relate the history of its discovery to the process of science

Going over how we take notes in this class

Explore: Cell TheoryBe the next Redi…

1.) Start with an observation that evokes a question - for each observation write one inference 2.) Use logic and previous knowledge to state a Possible answer = Hypothesis:3.) Perform an experiment or test4.) Publish your findings: (aka write all of this down)5.) Verification by other scientists: make sure that Your other group members test your experiments and agree on the conclusions 6.) Test and retest… and retest.. And test again if multiple experiments continue to support your Hypothesis you have a theory!

How certain are you of your answers: 10%, 90% sure?

What other types of tests would you like to do (besides opening the bag and looking inside) to be able to tell what is inside? (x-ray, scale, etc)

Theories vs. Laws

•A Scientific Theory ▫ a well tested explanation that unifies a

broad range of observations. It is not just a guess but something that has

been repeatedly tested and proven

•How were our conclusions about the items in the socks similar to theories?

Theory vs. Law

•Scientific Law: ▫ This is a statement of fact meant to

describe an action or set of actions and generally accepted to be true and universal.

▫ They are accepted at face value based upon the fact that they have always been observed to be true. Ex: Law of Gravity

Theory vs. LawHow I think of it….

The biggest difference between a theory and a law is: that a theory is much more complex and dynamic - A law describes a single action. Theory describes an entire group of related phenomenon

Analogy:

A law is a sling shot: one moving part. It is what it is. Predictable.

A theory is an automobile: complex piece of machinery. Sometimes improvementsAre made to one or more components but the function remains the same

Cell Theory

What did people think before they knew there were cells?•Leading Theory: Spontaneous

Generation▫ People thought that living things came

from inanimate objects. For example: maggots would just appear out of nowhere in meat!

Where did the maggots come from?•One scientist named Redi observed that

flies were always on the meat before there were maggots.

•He thought that the maggots came from the flies, to prove this he designed an experiment….

Redi’s Experiment…

Spontaneous generation was disproven by Francesco Redi using meat and jars

•What did this experiment prove?▫LIVING THINGS ONLY COME FROM

OTHER LIVING THINGS▫ What do you think would have been the implications if we had

kept on believing that life comes from inanimate objects?

How we discovered cells.• Robert Hook

▫ In 1665 Robert Hook looked under a microscope and this is what he saw

• This is a picture of what a piece of dead plant looks like under a microscope.

• What observations can we make?

• What would you call these?

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First to View CellsFirst to View Cells

•Hooke’s Contribution▫Hooke is

responsible for naming cells Hooke called them “CELLS” because they looked like the small rooms that monks lived in.

Building off Hook

•How we discovered cells:

•Schleiden, Schwann amd Vorchow

How we discovered cells.• Scheliden

▫ In 1838 Matthias Scheliden looked under a microscope and this is what he saw

• This is a picture of living plant tissue.

• What observations can we make?

• What inference can we make about plants? Are they made of cells?

How we discovered cells.• Theodore. Comparing

Cell Discovery ▫ The next year,

Theodore Schwann looked under a microscope and this is what he saw This is a picture of

living animal tissue.• What observations can we

make?• What inference can we

make about animal tissue? Are they made of cells?

How we discovered cells.• In 1855, Rudolph

Virechow looked under a microscope and this is what he saw…

• What observations can we make?

• What inference can we make about where cells come from?

• http://www.youtube.com/watch?v=rgLJrvoX_qo&feature=related

All organisms are made of one or more cells.▫Some organisms are made up of one cell ▫Others are multicellular or made up of

many cells

Principal # 1

Skin CellsEwwww!

The cell is the most basic unit of life.

Principal # 2

All existing cells are produced by other living cells.

Principal # 3

Finishing up today.. Prepare for next class •Exit Slip •Homework:

▫Next class: bring: Eager minds! :) Text book Composition notebook Binder

Unit 5 – Cell SpecializationCell TheoryPlant vs Animal CellsEukaroytic vs Prokaryotic

Daily Objectives1. Understand the difference between a theory

and a law.

2. Outline the three assumptions of cell theory

3. Distinguish between a prokaryotic and eukaryotic cell

4. Identify the structures that differentiate between prokaryotic and eukaryotic cells.

Engage: How Small is a Cell?

•Predict: How many cells could fit in the period of this sentence?

•http://learn.genetics.utah.edu/content/begin/cells/scale/

A. Tend to be microscopicB. Have a few key structures:

i. are enclosed by a membrane.ii. are filled with cytoplasm.

I. All Cells

Bacterium(colored SEM; magnification

8800x)

cell membrane

cytoplasm

2 types of cells…

•Prokaryotic and Eukaryotic:

▫“Pro” means “before”▫“Karyon” means “kernel” (referring to the

nucleus)▫“Eu” means “true”

•So what does Prokaryotic mean?•What does Eukaryotic mean?

▫Smaller and simpler.▫Prokaryotic cells do not

have a nucleus.

▫Prokaryotic cells do not have membrane-bound organelles.

▫Example: bacteria

nucleus

cell membrane

organelles

cytoplasm

Prokaryotic Cells

There are many different types of bacteria▫Some can cause disease▫Some recycle important natural resources

through decomposition▫We use some bacteria to make food, particularly

milk products Cheese, yogurt, sour cream, buttermilk

Bacteria

▫Larger and more complex▫Eukaryotic cells have a

nucleus and membrane-bond organelles

▫Prokaryotic cells do not have membrane- bound organelles.

▫Example: Plant and animal cells.

Eukaryotic Cells

nucleus

cell membrane

organelles

Prokaryotes Eukaryotes

▫ Smaller and simpler

▫ Do not have a nucleus.

▫ Do not have membrane-bound organelles.

▫ Larger and more complex.

▫ Eukaryotic cells have a nucleus and membrane-bound organelles

▫ Contain genetic information.

Remember, eukaryotic cells are those that have a true nucleus and have organized, complex organelles.

Both PLANT and ANIMAL cells fall under the category of Eukaryotic Cells.

** Eukaryotic Cells: **

Challenge Question (1 point)

•Which of the following is considered the basic building block of life?a) The cellb) The organc) The tissued) The organism

Challenge Question 2 (1 point)

Which statement is TRUE?▫All cells contain membrane-bound

organelles.▫All organisms have specialized cells to

perform life’s functions.▫All cells come from other pre-existing

cells.▫All cells arise from inorganic materials

through spontaneous generation.

Super Challenge! (2 points)

•What part of cell theory is the diagram to the right evidence of?

Super Challenge #2!! (2 points)•Are all cells microscopic?

▫If yes, explain why.▫If no, provide an example.

An ostrich egg is a single cell and is the biggest cell known!

Practice!

•Is it prokaryotic or eukaryotic?

Is it prokaryotic or eukaryotic?

Is it prokaryotic or eukaryotic?

Challenge Question! (1 point each)•What is structure 1?•What is structure 3?•Is this a plant or animal cell? Why?

1

2

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Independent Practice (BY YOURSELF)Either write the question or answer in complete sentences.

•Page 1 of the homework packet.