1. Life is Cellular

2. What is a cell?
A cell is the smallest unit that can carry on all of the processes of life.
All living things are made up of one or more cells.
All living things are made of organized parts, obtain energy from their surroundings, perform chemical reactions, change with time, respond to their environment, and reproduce.

3. Cellular Organization
Cell- smallest living unit!!!
Tissue – group of cells functioning together.
Organ – group of tissues functioning together.
Organ System – group of organs functioning together.
Organism – group of organ systems functioning together.

4. Discovery made possible by the invention of the microscope!!
History of the Cell
Discovery made possible by the invention of the microscope!!
New technology of the time!!
And…

5. Discovery of the Cell Mid 1600’s
English Scientist Robert Hooke: used early compound microscope to look at a slice of cork (multiple lenses)
thousands of empty chambers
called them “cells”
Cells were empty and not living

6. 1600’s. Microscopes and Cells
Anton van Leeuwenhoek (Holland) first described living cells as seen through a simple microscope.
Observed pond water and other living things
Saw tiny living organisms in the water people drank

7. Ideas that lead to the Cell Theory
1838- Matthais Schleiden
Plants were made of cells
1839- Theodor Schwann
Animals were made of cells
1855- Rudolph Virchow
New cells could only be produced from the division of existing cells

8. The 3 Parts of the Cell Theory
All living things are made of cells
Cells are the basic unit of structure and function of living things
New cells are produced from existing cells

9. Size of Living Things
1 m = 100 cm = 1,000mm = 1,000,000 µm = 1,000,000,000nm
1mm = 1000 µm = 1,000,000nm
1 µm = 1000nm
Diagrams:

10. Sizes of cells Tiniest cell- mycoplasm bacteria .2 μm
1000 μm =1mm
Typical cells μm
Giant ameoba μm (can see with unaided eye)

11. Common characteristics of all cells
Surrounded by a cell membrane (barrier)
All contain biological information (DNA) at some point during the course of its lifetime.
A fluid filled interior made of mostly water (cytoplasm)

12. Two basic types of cells
Prokaryotic Cells (Prokaryotes)
Eukaryotic Cells (Eukaryotes)
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Diagrams:
Prokaryotic & Eukaryotic Cell, Mariana Ruiz

13. Prokaryotes vs. Eukaryotes
No nucleus (genetic information not found in nucleus)
No membrane bound organelles (cell structures)
Less complicated than eukaryotes
Smaller than eukaryotes
Ex: bacteria
Eukaryotes
Definite membrane bound nucleus; genetic material separated from rest of the cell
Contains membrane bound organelles
More complex; highly specialized
Larger than prokaryotes
Great variety- single celled to many celled (plants, animals, fungi, and protists)

14. Prokaryotes vs. Eukaryotes
Bacterium
(colored SEM; magnification 8800x)

15. Prokaryotes
Prokaryote cells lack a nucleus and membrane-bound organelles.
Still contains genetic material
ribosomes
Many have cell walls

16. Exploring the cell with advancements in technology
Overtime studying cells has become easier due to technology
Video technology (movies of growth and development)
Fluorescent labels (follow molecules in cells)
Electron microscopy- see more details of cells
Scanning probe microscopes- trace surfaces of samples with a fine probe (can see single atoms)
Can operate in air and show samples in solution

17. The Cell’s Interior The cytoplasm
All cell’s contain a fluid filled interior made of mostly water
Many chemical reactions essential for life take place with in the cytoplasm
In eukaryotes- portion of the cell outside the nucleus
Cells need the correct balance of water, ions, organic compounds and gases to sustain homeostasis
Wastes are also produced within the cell which need to be released from the cytoplasm

18. Basic Organelles of all Eukaryotic Cells
Nucleus
Cell membrane
Mitochondria
Endoplasmic Reticulum
Ribsomes
Golgi Apparatus
Vesicles
Peroxisomes
lysosomes
Cytoskeleton
Centrioles (only in animal cells), cilia, flagella, filaments, micotubules