Download Cell`s Alive

Levels of Organization
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Molecules
Cells
Tissues (next slide)
Organs
Organ systems
Organism
Population
Community
Ecosystem
Biosphere
• Molecule
– The smallest particle of a substance that retains
the chemical and physical properties of the
substance and is composed of two or more
atoms held together by chemical forces
• Cell
– The basic unit of structure and function for all
living organisms
Tissues and organs
• Tissue
– An anatomical unit composed of cells organized to
perform a similar function
• One kind of cell makes up tissue
• Organ
– An anatomical unit composed of tissues serving a
common function
• Consists of different tissues
• Organ System
– An anatomical system composed of a group of
organs that work together to perform a specific
function or task
• Organism
– A form of life; animal, plant, fungi, etc.
• Population
– A group of individuals of the same species
living in a specific geographical area and
reproducing
• Community
– Different populations of organisms interacting
in a shared environment
• Ecosystem
– A system composed of organisms and nonliving
components of an environment
Biome – a large area or geographical
region with distinct plant and animal
groups adapted to that environment
Biosphere – the zone of life on earth: sum total of all
ecosystems on earth
The history of the cell
• Exploring the cell…
A Time line
• 1665 Robert Hooke-looked at cork using one of the first
microscopes.
• Coined the term “cells”
1674 Anton van Leeuwenhoek – views tiny living organisms in pond
water.
1831 Robert Brown – discovered the cell’s nucleus
1838 Matthias Schleiden – concludes that all plants are made up of
cells.
1839 Theodor Schwann – concludes that all animals are made up of
cells
1855 Rudolph Virchow – proposes that all cells come from existing
cells
Cell Theory
• Completed in 1855
1. All living things are made of one or more
cells.
2. Cells are the basic units of structure and
function in living things
3. All cells come from other cells
Prokaryotes and Eukaryotes
• The two main cell categories
• Classified on whether they contain a
nucleus or not.
Prokaryotes
• Do Not contain a nucleus
– DNA within the nucleoid region
• No membrane bound organelles
• DNA spread throughout the cell
• Contain a cell membrane
• Contain a cell wall
• Contain ribosomes
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Bacteria are prokaryotes
Label the prokaryote cell with the following
– DNA (nucleoid region), ribosomes, cell wall, cell membrane, flagella, pili
Images of Bacteria - Prokaryotes
Soil bacteria
Pseudomonas aeruginosa
E. Coli
Staphylococcus aureus
Endosymbiosis
eukaryotic cells were formed from simpler prokaryotes
• Endo – within
• Symbiosis – together
– Organisms living together, within one another
– Bozeman science video-endosymbiosis
https://www.youtube.com/watch?v=-FQmAnmLZtE
Eukaryotes
• Contain a nucleus
– Contains genetic material (DNA) inside.
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Contain membrane bound organelles
All have a cell membrane
Contain ribosomes
Some have a cell wall
Generally larger than prokaryotes
Eukaryote Cells
plant
Animal
Examples of eukaryotes
• Some Eukaryotes are single-celled organisms
Plants, animals, fungi and protists are examples of
multicellular eukaryotes.
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