Who discovered cells?
Robert Hooke who also coined the term Cell
Cell theory
all living things are made of cells, all cells come from other cells, cells are the basic unit of life
4 basic parts of prokaryote
plasma membrane (thin separation of intra and extra), cytoplasm (has jelly-like cytosol), dna (circular), ribosome (makes protein from genetic info)
4 additional parts in prokaryotic
cell wall (protection/shape), capsule (outer coating), pilus (helps attach to surfaces or exchanging dna), flagellum (whip that rotates like propeller for movement)
Typical eukaryote vs prokaryote
nucleus (linear strands instead of circular), 10x bigger than prokaryote, organelles
Endosymbiosis
at some point eukaryotic cells swallowed prokaryotes that turned into organelles
3 basic parts of eukaryotic animal cell
nucleus, cytoplasm, membrane
Differences between Animal cell and plant cell
animal has centriole and plant has chloroplast, cell wall, and vacuole
Evidence of endosymbiosis
chloroplasts and mitochondria are same size as prokaryotes, divide by splitting, have ribosomes, small amounts of circular dna (unlike linear dna in nucleus), and chloro/mito dna is similar to bacterial dna than dna in eukaryote
Invagination
other organelles are plasma membrane in eukaryote folded into itself and formed smaller parts that became specialized
Cell membrane functions
holds contents of cell, takes in food/nutrients/water, exports stuff, interacts with external env, has 2 layers (which are made of phospholipids) with proteins inside
Plasma membrane phospholipid bilayer structure
two layers of many sets of hydrophilic head and hydrophobic tails that form a barrier inside and outside the cell (almost like a row of individual magnets)
Molecules within membrane
carbohydrate chains (helps be Identified by other cells), cholesterol (for membrane flexibility), receptor proteins (binds to external chemicals to be used for internal processes), recognition proteins (helps be Identified by other cells), transport proteins (molecules pass into cell), membrane enzymes (intracellular and extracellular reactions)
Faulty membranes
leads to disease and abnormal cells, e.g. cystic fibrosis is inherited defect, OR can be intentionally disrupted using drugs for treatment
Membrane fingerprints
cells have molecular fingerprint that body understands, and the body will fight off foreign cells
Passive transport
molecules moving through membrane without energy (diffusion, osmosis)
Diffusion
solute dissolving in solvent and passing from high concentration to low concentration, simple or facilitated (help from channel/carrier molecule), e.g. breathing higher concentration of oxygen in air moves to lower concentration of oxygen in lung cells
Osmosis
diffusion of water across membrane
Isotonic solution
solute and water is balanced in and out of cell
Hypotonic solution
solute is higher in cell, so water moves into cell
Hypertonic solution
solute is higher out of cell, so water moves out of cell
Active transport
using energy to transport molecules through membrane, primary, secondary
Primary Active Transport
ATP fuels transporting, needed if molecules are very large or moving against natural concentration gradient
Secondary Active Transport
transport molecules move one molecule against concentration gradient and let second type of molecule flow down concentration gradient, analogy is like pumping water up a water tower, and then letting the water flow later to power something else
