What is a distinction between prokaryotes and eukaryotes?
prokaryotes– no compartmentalization
- DNA is in the nucleoid region rather than a nucleus
what does a prokaryote have?
plasma membrane, cell wall, ribosome, DNA, cytoplasm
7 common features of all cells
- Surrounded by plasma membrane
- Unique internal environment
- Store, replicate, transmit genetic information
- Divide/reproduce
- Metabolism
- Responds to external environment
- Limited in size
How does the plasma membrane play a role in limiting the size of a cell?
semi-permeable; difficult for material to pass through
WHy is it advantageous to maximize surface area to volume ratio
small cells- high SA:V- more efficient in transporting material- can cover more SA over volume
Key features of the nucleus
i. Contains most DNA
ii. Highly visible
Define the nuclear membrane
a) Double membrane, separates nucleoplasm from cytoplasm
b) Passage via nuclear pores
i) Protein complexes
ii) Highly regulated
How were the mitochondria and chloroplasts acquired?
through endosymbiosis
Describe mitochondria
a) Aerobic respiration
Present in all eukaryotic lineages- plants and animal
describe chloroplasts
a) Photosynthesis
b) Found in photosynthetic lineages- plants and algad
Key differences in mitochondria and chloroplasts
chloroplasts: photosynthesis, in plants, have one more membrane
Mitochondria: cell respiration, in plants AND animals, one less membrane
Evidence for endosymbiosis
- Double membranes-big cell ate small cell
- Similar size, morphology, enzymes, ribosomes to bacteria
- Has their own DNA - similar to living bacteria
- Divide via binary fission
Describe ribosomes
· Structures responsible for protein synthesis
· Not membrane bound- not considered organelles
· Made of protein and RNA
· Found in cytoplasm & associated with ER
Define the endomembrane system
· Internal Membrane system
- Divide cell into compartments - membrane bound organelles for organization
Direct continuity membrane communication
® Once you enter the system, you can go wherever you want- works if there is one compartment
Vesicular transport membrane communication
use vesicles to go from one compartment to the other
Describe the ER
- Internal Membrane complex
- Single contiguous lumen (internal space)
- Connected to outer membrane of nuclear envelope
define rough ER
ribosomes to outer surface
◊ Proteins made–> transported into lumen
define smooth ER
lipid synthesis metabolism
Very little; in specific cells- e.g. in liver
define Golgi Apparatus
Membranes, no contiguous lumen
Modify and transport proteins & Lipids
Define vacuoles
- Large vesicles derived from endomembrane system that functions as Food vacuoles, contractile vacuoles, storage in plant cells
CC vacuoles and vesicles
Vesicles: small and temporary
vacuoles: Large and persistent
Define lysosomes
- Compartments containing hydrolytic or digestive enzymes
How do Lysosomes work?
- Enzymes made in RER, processed in Golgi- inactive until food present
- Activated by fusing with food vacuole
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Memory & Learning11
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Foundations of Biology20
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Biological Molecules35
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Origins of Life31
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Cell Structure25
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Membrane & Transport34
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Metabolism30
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Photosynthesis25
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Cellular Respiration21
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Cell Cycle35
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Meiosis21
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Mendelian Genetics31
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13) Chromosomes24
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14) DNA36
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15) Gene Expression30
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Gene Regulation37
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17) DNA Technology35
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18) Human Genetics41
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19) Into to Evolution45
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20) Population Genetics40
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21) Speciation48
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22) Phylogentics35
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23) Population Genetics62
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24) Community Ecology42
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25) Ecosystem Ecology39
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26) Conservation Ecology43
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Photosynthesis & Cell Respiration Pathway6
