unit 2 big ideas
Big idea 1 Big idea 2 Big idea 3
- System interactions - Energetics - evolution
how would living systems function without what is the role of energy in the defend the origin of eukaryotic
the polarity of the water molecule? making and breaking of polymers? cells.
(4.2 prokaryotic cells in AP biology book, twelfth edition)
❖ cells:
➢ prokaryotic cells
■ lack a membrane- bound organelles
■ most abundant and diverse
■ don't keep DNA in an organelle
■ single coiled chromosome
■ extrachromosomal pieces of circular DNA called plasmids
➢ eukaryotic cells
■ contain DNA in the nucleus
■ has internal membrane bound compartments called organelles
■ have multiple chromosomes
● prokaryotes are small and typically have one shape
○ rod-shaped bacterium → bacillus
○ spherical-shape → coccus
○ some rods are twisted → spirilla (rigid) spirochetes (flexible)
■ both can appear in pairs, chains or clusters
all cells have:
- cytosol: jellylike substance that holds the subcellular components
- ribosomes: made of RNA +protein, synthesizes protein
- plasma membrane: selectively permeable
A. plasma membrane
a. phospholipid bilayer embedded with proteins
b. regulation entrance and exit of substances in and out of the cytoplasm
i. in prokaryotes the membrane can form internal pouches called mesosomes, which
increase the internal surface area for the attachment of enzymes that are carrying
metabolic activities
B. cell wall
a. maintains shape of the cell
b. glycocalyx: layer of polysaccharides that lies outside the cell wall in some bacteria
i. organized and not easily washed off its called capsule
ii. slime layer is not organized and easily removed
iii. helps against drying out
iv. helps resist the host's immune systems
, v. helps attach to any surface
C. cytoplasm
a. semi fluid solution composed of water, enzymes, inorganic and organic molecules encased by
plasma membrane
b. prokaryotic DNA is found in the cytoplasm
c. ribosomes: (RNA + 2 protein subunits) proteins encoded by prokaryotic DNA synthesis
d. includes thylakoids, where chlorophyll and other pigments absorb solar energy to produce
carbohydrates
D. external structure (all made of protein)
a. flagella: appendages that push the cell forward
i. motile prokaryotes use it to propel themselves in water
b. fimbriae: bristlike fibers that sprout from the surface
i. help attach prokaryotes to surfaces
c. conjugation pili: rigid, tubular structures
i. used by prokaryotes to pass DNA from one cell to the other
E. reproduction
a. reproduce asexually by binary fusion
b. exchange DNA using the conjugation pili, external medium or viruses
(4.3 introduction to eukaryotic cells in AP biology book, twelfth edition)
cell theory
- all organisms are made of cells
- cells are the basic unit of structures and function in organisms
- cells come only from preexisting cells because they are self producing
endosymbiotic theory
1. only prokaryotes existed in different shapes and sizes
2. larger one consumed the smaller ones but did not get digested
3. remain inside and began to live in symbiosis
RNA sequence suggest the prokaryote origin
organelles work together to metabolize, regulate and conduct life processes
production of specific molecules happens in surface of organelles then transported around by vesicles
- vesicles move around by means of an extensive network or lattice of protein fibers (tracks)
- membranous sacs that enclose molecules and separate them from the cytoplasm
cytoskeleton: maintains cell shape and helps in movement
Big idea 1 Big idea 2 Big idea 3
- System interactions - Energetics - evolution
how would living systems function without what is the role of energy in the defend the origin of eukaryotic
the polarity of the water molecule? making and breaking of polymers? cells.
(4.2 prokaryotic cells in AP biology book, twelfth edition)
❖ cells:
➢ prokaryotic cells
■ lack a membrane- bound organelles
■ most abundant and diverse
■ don't keep DNA in an organelle
■ single coiled chromosome
■ extrachromosomal pieces of circular DNA called plasmids
➢ eukaryotic cells
■ contain DNA in the nucleus
■ has internal membrane bound compartments called organelles
■ have multiple chromosomes
● prokaryotes are small and typically have one shape
○ rod-shaped bacterium → bacillus
○ spherical-shape → coccus
○ some rods are twisted → spirilla (rigid) spirochetes (flexible)
■ both can appear in pairs, chains or clusters
all cells have:
- cytosol: jellylike substance that holds the subcellular components
- ribosomes: made of RNA +protein, synthesizes protein
- plasma membrane: selectively permeable
A. plasma membrane
a. phospholipid bilayer embedded with proteins
b. regulation entrance and exit of substances in and out of the cytoplasm
i. in prokaryotes the membrane can form internal pouches called mesosomes, which
increase the internal surface area for the attachment of enzymes that are carrying
metabolic activities
B. cell wall
a. maintains shape of the cell
b. glycocalyx: layer of polysaccharides that lies outside the cell wall in some bacteria
i. organized and not easily washed off its called capsule
ii. slime layer is not organized and easily removed
iii. helps against drying out
iv. helps resist the host's immune systems
, v. helps attach to any surface
C. cytoplasm
a. semi fluid solution composed of water, enzymes, inorganic and organic molecules encased by
plasma membrane
b. prokaryotic DNA is found in the cytoplasm
c. ribosomes: (RNA + 2 protein subunits) proteins encoded by prokaryotic DNA synthesis
d. includes thylakoids, where chlorophyll and other pigments absorb solar energy to produce
carbohydrates
D. external structure (all made of protein)
a. flagella: appendages that push the cell forward
i. motile prokaryotes use it to propel themselves in water
b. fimbriae: bristlike fibers that sprout from the surface
i. help attach prokaryotes to surfaces
c. conjugation pili: rigid, tubular structures
i. used by prokaryotes to pass DNA from one cell to the other
E. reproduction
a. reproduce asexually by binary fusion
b. exchange DNA using the conjugation pili, external medium or viruses
(4.3 introduction to eukaryotic cells in AP biology book, twelfth edition)
cell theory
- all organisms are made of cells
- cells are the basic unit of structures and function in organisms
- cells come only from preexisting cells because they are self producing
endosymbiotic theory
1. only prokaryotes existed in different shapes and sizes
2. larger one consumed the smaller ones but did not get digested
3. remain inside and began to live in symbiosis
RNA sequence suggest the prokaryote origin
organelles work together to metabolize, regulate and conduct life processes
production of specific molecules happens in surface of organelles then transported around by vesicles
- vesicles move around by means of an extensive network or lattice of protein fibers (tracks)
- membranous sacs that enclose molecules and separate them from the cytoplasm
cytoskeleton: maintains cell shape and helps in movement
