Did you say Cells?Yes I said Cells!

YAH CELLS!!!!!!!!!!!!!

The Big Discussion on Cells

Living ThingsAll living things have

a cellular organization, contain similar chemicals, use energy, grown and develop, respond to their surroundings, and reproduce.

These are the 7 major characteristics of life!

What is a Cell?All organisms are

made of small building blocks called cells.

A cell is the basic unit of structure and function in an organism.

Cell Sizes can varyMost cells are small,

about 40 human cells would fit on the dot of this letter i.

Some cells are big, the yolk of a chicken egg is a single cell.

The smallest cells are so tiny that you could fit over a million of them on the period at the end of this sentence.

Cell SizeCells are made of

moleculesMolecules are tiny

particles of matter.Molecules are made

up of atoms.The atom is the

basic fundamental unit of matter. Atoms are made up of

protons, neutrons and electrons.

How Many Cells Make Up Organisms?

Organisms can be composed of only one cell or many cells.

Unicellular or single celled organisms include bacteria the most numerous organisms on Earth.

Multi-cellular organisms are composed of many cells.

You are made up of trillions of cells.

You have specialized cells in your body that perform specific functions.

Chemicals of LifeThe most abundant

chemical in cells is water.Other chemicals are called

carbohydrates and these are the energy source for the cell.

Two other chemicals are proteins and lipids which are the building materials for cells, much like wood and bricks are the building materials of houses.

Finally nucleic acids are the genetic material.

Cells use EnergyThe cells of organisms use

energy to do what living things must do, such as grow and repair injured parts.

Cells are always hard at work.

Right now your cells are busy not only with your eyes and brain but your blood cells are moving chemicals around your body.

White Blood Cells are pictured to the right!

How do we look at Cells?The invention of the

microscope made it possible for people to discover and learn about cells.

A microscope is an instrument that makes small objects look larger.

A light microscope that has more than one lens is called a compound microscope.

The Top 10 Microscope IMAGES!!!

Cool Microscopic Images

Who discovered that we have Cells?

One of the first people to observe cells was the English scientist Robert Hooke.

In 1663, Hooke observed the structure of a thin slice of cork using a compound microscope.

To Hooke the cork looked like rectangular rooms, which he called cells.

Who discovered that we have cells?

At about the same time that Robert Hooke made his discovery, Anton van Leeuwenhoek also began to observe tiny objects with his microscope.

Leeuwenhoek was a Dutch scientists and when he looked at water from a pond he saw tiny single celled organisms.

The Cell TheoryObservations from

Hooke and Leeuwenhoek led to the development of the cell theory.

The cell theory states:All living things are

composed of cells.Cells are the basic unit

of structure and function in living things.

All cells are produced from other cells

Looking Inside CellsCells contain even

smaller structures inside of the cell called organelles.

Organelles were called organelles because early scientists thought they looked like “inner organs” kind of like our heart, kidneys, or brain.

Parts of the Cell: Cell WallThe Cell Wall is a rigid

layer of nonliving material that surrounds the cells of plants and some other organisms.

Cell Walls look rectangular and shape and are only found in plant cells.

A plants cell wall helps to protect and support the cell. It provides a rigid support stand for the cell and also helps keep out some harmful substances.

Parts of the Cell: Cell Membrane

In plant cells the next layer inward is the cell membrane.

In animal cells the cell membrane forms the outside boundary that separates the cell from its environment.

The cell membranes main function is that it controls what substances com into and out of the cell.

For example it will let food and oxygen in but keep out harmful waste products.

Parts of the Cell: NucleusThe nucleus is a large

oval structure inside the cell.

The nucleus is the cell’s control center that directs all of the cells activities.

It’s really the Brain of the Cell!

The nucleus does have a nuclear membrane which is an inner protection system for the cell to protect it’s nucleus.

Parts of the Cell: NucleusInside the nucleus you

have DNA (Deoxyribonucleic acid) This is what helps cells reproduce and tells them what they should do and look like

This is why you look like a combination of your mother and father because you have DNA from both of your parents.

Parts of the Cell: CytoplasmThe region between

the cell membrane and the nucleus is known as cytoplasm.

This is a clear, thick, gel-like fluid.

Many of the cell’s organelles are found in the cytoplasm.

Parts of the Cell: Mitochondria

Inside the cytoplasm you can find rod shaped structures called mitochondria.

Mitochondria are called the powerhouses of the cell because they produce most of the energy the cell needs to carry out its functions.

Muscle cells rely heavily on mitochondria.

Parts of the Cell: Endoplasmic Reticulum

The endoplasmic reticulum (ER) looks like a giant maze of passageways.

The endoplasmic reticulum is responsible for moving proteins and other materials from one part of the cell to another.

Parts of Cells: RibosomesAttached to the outer

surface of the endoplasmic reticulum are small grain-like bodies called ribosomes.

Ribosomes function as factories that produce proteins for the cell.

From the ribosomes and endoplasmic reticulum the proteins are transported to the golgi apparatus.

Parts of the Cell: Golgi BodiesWithin the

endoplasmic reticulum you will find a flattened collection of sacs and tubes. These are called Golgi Bodies.

The Golgi Bodies are like the cells mailroom. They receive proteins , package them, and distribute them to different parts of the cell.

Parts of the Cell: ChloroplastsOnly plant cells and

other protist type cells have chloroplasts.

The chloroplasts help capture energy from sunlight and use it to produce food for the cell.

The chloroplasts give plants their green color.

They are responsible for photosynthesis.

Parts of the Cell: VacuolesThroughout the cell

you can find large water-filled sacs floating in the cytoplasm.

These sacs are called vacuoles. Vacuoles store food and other materials needed by the cell.

All plant cells have a large central vacuole.

Parts of the Cell: LysosomesLysosomes are small

round structures that contain chemicals that break down large food particles smaller ones.

Lysosomes also break down old cell parts and release the substances so they can be used again

Parts of the Cell: Cillia and Flagella

Cillia are hair like structures that are found on bacteria and some protist cells. They are like a bunch of tiny ores that are used for movement

Flagella is a whip like structure that some bacteria and protists cells have. When they whip their tail they propel themselves through the water.

Bacterial CellsBacterial cells are

smaller than plant or animal cells.

Bacterial cells do have a cell wall and membrane but they do not have a nucleus.

Organisms whose cells lack a nucleus are called prokaryotic or the organsims prokaryotes.

Animal or Plant CellsAnimal and Plant

cells both have a nucleus so we call their cells eukaryotic or the organisms eukaryotes.

Bacteria vs. Plant vs. Animal Cell

How are Plant Cells and Animal Cells Different?

Plant Cells are rectangular in shape due to their Cell Walls.

Plant cells have chloroplasts which perform photosynthesis.

Plant cells have a large central vacuole. This helps regulate how much water the plants lets in or keeps out. It regulates osmosis!

Draw an Animal Cell

Draw a Plant Cell

Draw a Bacteria Cell

The Importance of CellsThink about every time you

need energy to move your cells have to actively be working so that you can move.

Think about every time you breathe in your individual cells have to take in oxygen and use it to make energy.

All of our energy needs are met by small tiny parts of our body that we barely even think of.

Transport within Cells Diffusion is the movement of

molecules from a high concentration to low concentration.

Diffusion does not require energy use. It’s kind of like riding your bicycle down hill. You still get somewhere and you still move but you don’t have to use the pedals.

Diffusion is a type of passive transport.

Sometimes protein channels can help in moving materials into the cells. They are embedded in the cell membrane.

Transport within CellsActive transport is the

movement of materials through a cell membrane using energy.

By doing so cells have move molecules into the cell that they need but this requires energy because there is not a concentration difference.

This type of transport is kind of like riding a bicycle up hill you get to your destination but it requires energy to do so.

Osmosis and DiffusionRemember that diffusion is

when you have particles move from high concentration to low concentration.

Remember that osmosis is when you have water move from high to low concentrations.

This is important when plants regulate their water supplies.

Red Blood Cells can burst if they don’t use osmosis correctly.

What causes Diffusion?Molecules are always

moving. As they move, the molecules bump into one another. The more molecules there are in an area, the more collisions there will be.

Collisions cause molecules to push away from one another.

Over time, the molecules of a substance will continue to spread out.