CellsBasic unit of life!

Everything from a bacteria to you and I are made up of cells

We have more than 100 trillion cells in our bodiesThe brain has over 30 billion cells

Groups of cells make up TISSUES in your body

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Groups of TISSUES make up Organs

Groups of ORGANS make up Organ Systems

Cells - basic unit of life

History of Cell Discovery

1665 - Robert Hooke saw cells in cork

Cellulae - tiny rooms

1675Anton van Leeuwenhoek

looked at different samples of blood, rainwater, and even his own teeth scrapings

In rainwater he saw tiny “animals”

BACTERIA

1831Robert Brown

Discovered the nucleus in plant cells

During the next 200 years a lot happened

Matthais Schleiden - 1838 all plants are made up of cells

Theodor Schwann - 1839 all animals are made up of cells

Rudolph Virchow - 1855 all living cells come from other living cells

Cell Theory

All living things are made of cellsCells are the basic units of structure and function

Living cells only come from living cells

Today - There are even more facts

Cells have different shapes and sizes

Cells have different internal organization

Prokaryotes - do not have a nucleus or membrane bound organelles

Pro - means before (before the nucleus)

Eukaryotes- Have a nucleus and membrane bound organelles

Prokaryotes Eukaryotes

Tissues

Organs

Organs systems

Cells

Cells; The Basic Units of Life

                                  

Cell Theory

• All Living things are made of cells• The cell is the basic unit of life• All cells come from other living things

What are the two types of cells?

• Eukaryotic- because they have nuclei (all other living kingdoms) video

• Prokaryotic- they DON’T have nuclei (bacteria) (video)

Types of Cells

Major Organelles of the Cell

      

Cell MembraneMade of proteins and lipids that separates the

inside cytoplasm & organelles from the outsideAllows few things to enter the cell.Allows many things to exit the cell.

Functions of the cell membrane

• Protection of organelles inside the cell

• Permeation of substances• Gives the cell its shape• Selectively permeable membrane

that allows only certain substances through

Cell Wall (bacteria)

Cell Wall (plant cell)

Nucleus• The control center of the cell.• DNA is present here in the form of

chromosomes• It has its own protective membrane.• It is responsible for the overall function of

the cell. (The Brain of the Cell)• The nucleolus (dark spot inside the

nucleus) makes new ribosomes.

Nucleus

What allows certain things to enter the nucleus?

• The nuclear envelope; which is a membrane around the nucleus only. It has small pores in it to allow information and ribosomes to leave the nucleus, but keeps everything else from entering the nucleus.

Functions of cytoplasm: (sometimes called protoplasm)

• It keeps all the organelles protected.

• It gives the cell its shape.• The actual liquid is called the

CYTOSOL, the area is called the cytoplasm. (video)

Mitochondria

Functions of mitochondria:

• It is the powerhouse of the cell because it converts nutrients into energy.

• It takes the energy we eat and converts it into a usable form through a process called GLYCOLYSIS (cutting of glucose)

ChloroplastResponsible for converting sunlight into energy

Functions of chloroplasts:

• It is responsible for trapping sunlight for energy.

• Photosynthesis takes place in this organelle.

• Chlorophyll is the chemical that causes plant cells to be green.

Ribosomes

• Responsible for assembling proteins.• Located throughout the cytoplasm.• Also found on the endoplasmic reticulum.

Functions of ribosomes:

• They assemble nutrients into molecules of protein to be used by the mitochondria.

Endoplasmic ReticulumTransports nutrients throughout the cell

What is the function of the ER?

• It transports materials to be used throughout the cell.

• There are two types:• 1. Rough ER - appears bumpy• 2. Smooth ER

What is the difference between smooth er and rough er?

• Smooth ER does not have ribosome on it.– Functions: produces lipids and detoxifies drugs

and poisons, also helps with muscle contraction

• Rough ER has ribosomes found on it.– Antibody production occurs here. The Rough

ER is also involved in production of damaged membranes

LysosomesResponsible for cleaning the inside of the

cell.

What is a lysosome?

• It is the cleaning organelle. It breaks up all the waste and dead material found in the cell.

• Also recycles cells when damaged.• Its enzyme, lysozyme, inside has a

pH of 5 which breaks down materials quickly

Golgi Apparatus- Storage area for proteins

Functions of the Golgi Apparatus:

• It breaks down large molecules so that they can be utilized throughout the cell.

• Usually called the post office - sends, stores and ships molecules

• Series of flattened membranous sacs, which release vesicles delivering proteins and other materials to the rest of the cell

Vacuoles- Storage for nutrients in plant and animal cells- Contains unused water and/or nutrients

What is the function of a vacuole?

• It stores all nutrients and reserve energy. (video)

What are some differences between plant & animal cells???

• Presence of a chloroplast in plant cells

• Presence of a cell wall for prevention of water loss and structure in plant cells

• Large vacuole in a plant cells for long-term nutrition and storage

Homemade Playdoh Recipe

• 3 c Flour

• 1 1/2 c Salt

• 3 tbsp Oil

• 1 c Water

• 1 tbsp Food coloring

• Mix all ingredients in a big bowl. May be separated into 4 to make 4 different colors.

Cell Quiz

• 1. What organelles the NUCLEUS hold? What is its function?

• 2. What are 2 functions of the cell membrane?

• 3. What are the 3 parts of the cell theory?

• 4. What is the liquid AREA of the cell called?

• 5. What processprocess takes place in the CHLOROPLAST?