Transcript Introduction to Cells

CELLS
The Building Blocks of Life
What is a Cell?
• Small units that carry out all of an
organism’s life activities.
Plant, Animal and
Bacterial Cells
• Eukaryotic – plant
& animal
– Nucleus (protects
DNA)
• Prokaryotic –
bacteria
– No nucleus (DNA
floating inside cell)
Eukaryotic
(plant & animal cells)
Prokaryotic
(bacterial cells)
Cytology
• The branch of life science, which deals
with the study of cells in terms of
structure, function and chemistry.
– Cytopathology: the study of cellular disease
and the use of cellular changes for the
diagnosis of disease.
– Cell Biology: the study of (normal) cellular
anatomy, function and chemistry.
Important Contributions
• Hooke
• Leeuwenhoek
• Virchow
• Schleiden
• Schwann
Who Did What?
• Robert Hooke
• Discovered cells when he
looked at cork.
• Anton van
Leeuwenhoek
• Discovered bacteria and
protists.
• Mathias Schleiden
• Studied plants and plant
cells.
• Theodor Schwann
• Studied animals and
animal cells.
• Discovered that living cells
only come from other
living cells.
• Rudolph Virchow
The Cell Theory
• All organisms are composed of one
or more CELLS.
• The cell is the basic unit of LIFE in all
living things.
• All cells come from EXISTING cells.
Cells . . .
The Building Blocks of Life.
Levels of Biological
Organization
The Cell
• Bacteria
• Somatic Cells
–
–
–
–
–
–
–
Skin
Bone
Muscle
Red blood
White blood
Cheek
Leaf
• Sex Cells
– Egg
– Sperm
The Cell
• Unicellular
– Made of a single cell.
• Multicellular
– Made of many cells.
• Organelles
– “Tiny Organs”
– Structures within a cell
that help it live, grow
and reproduce.
– All cells have a cell
membrane, cytoplasm
and DNA (nuclear
material).
Tissues & Organs
• Tissues
– Several cells working
together.
– Cells working in teams.
– Ex. – muscle, nerve
xylem, phloem
• Organs
– Several tissues working
together.
– Ex. – stomach, heart,
leaf, roots, stem
Organ Systems & Organisms
• Organ Systems
– Organs working
together.
– Ex. – digestive,
respiratory, nervous,
excretory,
cardiovascular, leaf &
root system
• Organisms
– Independent living; any
living thing.
– Ex. – animal, plant,
fungi, protists, bacteria
Think Big . . .
• Population
• Community
• Ecosystem
• Biome
• Biosphere
• Organisms of the same kind living in
the same area; deer in a forest, fungi
growing on a rotting log.
• Two or more populations living in
the same area; foxes, oak trees,
lizards & flowers in a forest.
• Communities of living organisms and
abiotic factors in an area; rivers,
lakes, small forests, prairies, your
own backyard.
• Ecosystems co-existing in a large
geographical area; deciduous forest,
tundra, desert, marine.
• The Earth and surrounding
atmosphere supporting all life.