What are all living things made of?

All living things are made up of cells.cells.

You have seen two cells, an amoeba and a paramecium. What did you notice about their sizes?

They are really small, microscopic.

What is needed in order to see cells?The microscope needed to be invented and improved in order to see cells clearly

If you couldn’t see something, how would you know it exists?

The invention of the compound microscope by Zacharias Janssen in the late 1500’s allowed for the study of cells to occur

– Cytology Cytology is the study of cellscells

Cell Study and DiscoveryCell Study and Discovery

• Anton van Leeuwenhoek (1678) - Used simple scopes to see “animalcules”– First to observe bacteria and protists

• Robert Hooke (1665) – Observed cork. First to use the term “cells”“cells”

• Matthias Schleiden (1888) – All plants are made up of cells

• Theodore Schwann (1889) – All animals are made up of cells

• Rudolph Virchow (1889) – Cells come from pre-existing cells.

**The Cell Theory****The Cell Theory** • All living things are made up of cells

• Cells are the basic unit of structure and function in all living things

• Cells come from pre-existing cells

All living things are made up of cells.

What in this room is like a cell?

What is a cell?

Cell Cell – Basic unit of structure and function in all living things

Would a microscopic organism like a bacteria need to be very complex?

Bacteria are simple, very small organism that can control what comes in and out of them, and can reproduce themselves because they have DNA and structures called ribosomes (for protein synthesis)

Types of cellsTypes of cells 1.1. Prokaryotic cellsProkaryotic cells

– Primitive cells – “before the nucleus”

– *No *No nucleus*nucleus*– No organelles

surrounded by a membrane

– Found in bacteria– Have only a cell wall, cell

membrane, cytoplasm, DNA & ribosomes

Cell Wall

DNA

DNA

What about our cells that are specific to their function? Do they need to be more complex?

Yes or No? Why?

Since our cells have specific functions, there is a greater level of complexity

2.2. EukaryoticEukaryotic

*“True nucleus”*– Have membrane –

bound organelles– All other

kingdoms except bacteria

• Contain Organelles

– Specialized structures within the cytoplasm to perform distinct processes within the cell

Comparing the Two

Cell Membrane

Cytoplasm

DNADNA

Structures common to both Prokaryotic & Structures common to both Prokaryotic &

Eukaryotic cellsEukaryotic cells • Cell Membrane• Ribosomes• DNA• Cytoplasm• Cell Walls (not in Animal or some Protist

cells though!)

Prokaryotic Cell - Bacteria

DNA

Cell Membrane

Eukaryotic Animal Cell

Cell Membrane

Eukaryotic Plant Cell

CytoplasmCytoplasm– The jelly-like fluid filled area within a cell– Like our blood plasma, contains dissolved

monomers like glucose, amino acids, nucleotides, fatty acids and glycerol, vitamins and mineral plus ionic substances like NaCl

CytoskeletonCytoskeleton- Network of protein

strands that provide support and mobility of organelles in cytoplasm.

- 2 components of cytoskeleton - Microfilaments and Microtubules (both made of protein)

NucleusNucleus– Only in Eukaryotic cells. – *Stores hereditary information

(DNA). – Surrounded by a double nuclear double nuclear

membranemembrane or envelope w/ pores .– NucleolusNucleolus (1 or >) produces

ribosomes

Nuclear Membrane

Nucleolus

DNA

Prokaryotic or Eukaryotic?How do you know?

MitochondriaMitochondria

- *Powerhouse of the cells.

- Supplies energy to the cell (*Site of Cellular respiration)

- Double membrane with inner membrane folded to increase surface area

- Has its own DNA and ribosomes and can replicate themselves!

- Found in greater numbers in cells such as muscle cells & liver cells (2500/cell)

Cristae

Double Membrane

Ribosomes Ribosomes – Most numerous organelle.

*Site of protein synthesis. Link amino acids together to form proteins

Made up of RNA and protein.

May be free floating in cytoplasm or attached on Endoplasmic Reticulum

Endoplasmic ReticulumEndoplasmic Reticulum

– Maze of folded channels connected to the nuclear envelope. .

• There are two types of ER:

1 – Rough w/ ribosomes attached for production & distribution of proteins.

2 – Smooth – Synthesis of lipids & detoxification of toxins.

*Many in the liver

Golgi Apparatus (Bodies)Golgi Apparatus (Bodies)

– Stack of smooth flat sacs

- Modifies, collects, packages & distributes molecules to all

parts of a cell

Lysosomes Lysosomes

- *Stores digestive enzymes – Are the cells' garbage disposal system.

They breakdown worn out organelles – Clean up dead cells– Responsible for the un-webbing of hands

of fetus while developing in utero– These are rare in plant cells

VesiclesVesicles– Temporarily isolate and Temporarily isolate and transport specific transport specific

moleculesmolecules– Proteins produced in the RERProteins produced in the RER– Lipids produced in the SERLipids produced in the SER– End up in Golgi Apparatus to be End up in Golgi Apparatus to be

processed. processed.

VacuolesVacuoles

- *Stores food, water and wastes

- Plant cells have a very large central waterlarge central water vacuolevacuole for support

Acts like a giant water balloon that pushes on the cell wall

- Animal cells have many small vacuoles

CentriolesCentrioles

– Found in animal cells

2 perpendicular bundles of microtubules

- Function during cell division      

Cell WallCell Wall• Found in plants, algae, fungus and bacteria • Gives cell rigidity, support and protection. • Made up of cellulose with pectin (glue) between

adjacent cells.

ChloroplastsChloroplasts - found in leaves and some - found in leaves and some stemsstems

Convert solar energy into energy rich molecules (glucose) - PhotosynthesisPhotosynthesis

• Contain Chlorophyll, DNA and ribosomes– They can replicate as needed (with more sunlight)

What does a plant cell have that an animal cell does not?

What does an animal cell have that a plant cell does not?

Cell MembraneCell Membrane – Present in ALL CELLS.- Separates the cell’s internal environment Separates the cell’s internal environment

from the external environment.from the external environment.- Allows for the passage of some substances Allows for the passage of some substances

based on size and concentration based on size and concentration - Selectively PermeableSelectively Permeable due to pores being

present

Made of a double layer of phospholipidsphospholipids

with proteins floating through it. • Outer part of membrane is

made up of polar, hydrophilic heads

• Inner part of membrane is made up of nonpolar, hydrophobic fatty acid tails

• Proteins through membrane allow for passage of materials across the membrane

• In the "fluid mosaic model" of membrane structure says that the molecules within the membrane move around.– Phospholipids regularly move sideways & flip– Proteins can not flip aroundRap

Cheek Cells Nucleus

Cytoplasm

Cell Membrane

Elodea

Onion Cells

Go to cellsalive.com

1. Nucleolus

2. Nucleus (envelope)

3. Rough Er

4. Vesicle

5. Ribosome

6. Golgi Apparatus

7. Cytoskeleton

8. Smooth ER

9. MITOCHONDRIA

10. Vacuole

11. Cytoplasm

12. Lysosome

13. Centrioles

Typical Animal Cell

Typical Plant Cell

1. Nucleus

2. Ribosomes

3. Mitochondria

4. Chloroplasts

5. Cell Membrane

6. Cytoplasm

7. Cell Wall

8. Central Vacuole

9. Golgi Apparatus

10.Rough Endoplasmic

Reticulum

1. _______________2. _______________3. _______________ (Dots)4. _______________5. _______________6. _______________7. _______________8. _______________9. _______________10._______________11._______________12._______________13._______________

Typical Animal Cell

1. Nucleolus

2. Nucleus

3. Ribosome

4. Vacuole

5. Rough ER

6. Golgi Apparatus

7. Microtubule

8. Smooth ER

9. Mitochondria

10. Vacuole

11. Cytoplasm

12. Lysosome

13. Centriole

Typical Animal Cell

Organelle Function Plant Cells Animal Cells

MitochondriaSite of cellular respiration - transfer of energy - Folds

called CristaeYes Yes

Ribosomes Site of Protein synthesis Yes Yes

Endoplasmic ReticulumRough - Protein packaging & transport site

Smooth - Sythesis of lipidsYes Yes

Golgi Apparatus Processing & packaging center for cell secretions Few Many

Lysosomes Produce hydrolytic enzymes Few Many

CytoskeletonNetwork of protein filaments - keep cell's shape and for

movementYes Yes

Microfilaments & microtubules

Support, movement and cell division Yes Yes

Cilia & FlagellaCell movement & circulation Cilia - many & short,

Flagella - 1or 2 & longYes Yes

Nucleolus Production of ribosomes Yes Yes

Nucleus Contains DNA, synthesizes RNA & Ribosomes Yes Yes

Nucleic Acid DNA & protein - genetic information Yes Yes

Cell WallOutmost layer of plant cell - support & protection Made

of cellulose & pectin glue between wallsYes No

VacuoleStores enzymes, wastes, water & food Large water in

plants - support

Yes, large water

vacuoleMany

Chloroplast Contains chlorophyll for Photosynthesis Yes No

Centrioles Microtubules that function during cell division No Yes

Cell Membrane Selectively permeable - made of a bilipid layer & proteins Yes Yes