1
The Cell
Cell background
Cell types
Animal cells
Plant cells
Cytoskeleton
Cell communication
Remember the Macromolecules?
All cells have
1.
Proteins—perform most of the cell’s functions
2.
Nucleic acids—store, transmit, and process
information
3.
Carbohydrates—provide chemical energy, carbon,
support, and identity
4.
phospholipid membrane—serves as a selectively
permeable membrane barrier
•
Cells were first described in 1665 by Robert Hooke.
Discovery of Cells
•
Cells were first described in 1665 by Robert Hooke.
•
The accumulation of scientific evidence over many years led
to the
cell theory
.
Discovery of Cells
Cell Theory
-
The cell is the basic unit of life
-
All living things are made from one or more cells
-
Cells are produced directly from the growth and
division of other cells.
-
Each cell can regulate its internal conditions
(homeostasis)
-
Homeostasis at the level of the tissue, organ, organ
system and organism reflects the combined and
coordinated actions of many cells.
•Why aren’t cells bigger?•Why have 1000’s when you would only need 100’s?Cells are Small
Surface Area:Volume
Ratio
Cell morphology: Prokaryotic vs Eukaryotic
Prokaryotes
Eukaryotes
No Nucleus
Nucleus
Few/simple organelles
complex organelles
Smaller
Larger
Evolved first
Evolved later
(3.5 BYA)
(2.1 BYA)
almost entirely
Some unicellular
unicellular*
Some multicellular
–
Based on morphology, there are two types of cell:
•
Prokaryotic cells (prokaryotes)
•
Eukaryotic cells (eukaryotes)
The Tree of Life: The three domains
•
Which are Prokaryotes / Eukaryotes?
