1The CellCell backgroundCell typesAnimal cellsPlant cellsCytoskeletonCell communication
Remember the Macromolecules?All cells have1.Proteins—perform most of the cell’s functions2.Nucleic acids—store, transmit, and process information3.Carbohydrates—provide chemical energy, carbon, support, and identity4.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 EukaryoticProkaryotesEukaryotesNo NucleusNucleusFew/simple organellescomplex organellesSmallerLargerEvolved first Evolved later (3.5 BYA)(2.1 BYA)almost entirely Some unicellularunicellular* 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?