Chapter 7 Cellular Structure and

FunctionSection 1

Pages 182-186

What do you know about Cells?

Cells are Tiny!

• No one even knew about cells until the microscope was invented!!

Section 7.1: Cell Discovery and Theory• 1665 – Robert Hooke (U.K.)– Made a simple microscope and used it to observe

cork.– He saw small box-like structures and called them

cellulae (Latin for small rooms).– It is from Hooke’s work that today we have the

term cell(s).

Famous Old Guy1. Robert Hook- coined the term “cell” after

looking at cork.

• A cell is the basic structural and functional unit of all living organisms.

Not that kind of cell!!

History of the Cell Theory• 1683 – Anton van Leeuwenhoek (Dutch)– Designed his own microscope after reviewing

Hooke’s work.– Observed single-celled organisms in pond water,

milk, and other substances.

Famous Old Guy

1. Robert Hook - observed and documented the first cell2. Anton van Leeuwenhoek - invented first microscope; discovered “animal like” unicellular organisms.

Quick Check

• First person to see a cell?

• Person who invented Microscope?

The History Continues…• 1838 – Scientists discover plants are made of cells.• 1839 – Scientists discover that animal tissues

consist of cells.• 1855 – Scientists propose that all cells are

produced from the division of existing cells.

Microscope Technology• Developments in microscope technology

have given scientists the ability to study cells in great detail.

The Cell Theory – Includes Three Principles:

1. All living organisms are composed of one or more cells.

2. Cells are the basic unit of structure and organization of all living organisms.

3. Cells arise only from previously existing cells, with parent cells passing copies of their genetic material on to their daughter cells.

OMG THAT’S TOO MUCH TO WRITE!

Shorter please!

Cell Theory1. Organism = 1 or more cells2. Cells are the basic unit of life3. Cells come from other cells

Microscope Summary

1. Compound Light Microscope - Uses light 2. Electron Microscope- uses electrons and

magnets

• So now using the microscope we can see all kinds of different cells!

• Cells are different from one another just like people are. Cells differ based on the function they serve.

However…..• All cells have

1. A plasma membrane – a special boundary that helps control what enters and leaves the cell.

All cells also have…

2.Genetic Material3.The ability to break down

molecules.

Two Main Types of Cells

1. Prokaryotic Cells pro = beforekary = nucleus

PRO=NO!!2. Eukaryotic Cells eu = truekary = nucleus

Prokaryotic Cells• NO membrane bound organelles.• Most unicellular organisms (bacteria) are

prokaryotes.

Eukaryotic Cells– Bigger than prokaryotic cells– Contain organelles – Have a nucleus

Prokaryotic Cells Vs. Eukaryotic Cells

• Prokaryotic cells are much simpler in structure compared to eukaryotes.

• Scientists believe eukaryotic cells evolved from prokaryotic cells and that prokaryotes were probably the first form of life on Earth.

Organelles• Organelles are specialized structures that

carry out specific functions.

Yes your going to need to know all the organelles but that’s for another day!!

Review

• Name the two types of cells?• Name one similarity.• Name one difference.

7.1 Activity

• Make a Venn diagram of Prokaryotic and Eukaryotic cells.

• Answer the questions on the Back.• If its not done its Homework.