Cells Flashcards
What is Cell Theory?
- All organisms are composed of cells.
- Cells are the smallest living things.
- Cells only arise from pre-existing cells.
- Cells are the basic unit of life.
What is the characteristic of cell size?
Cell size is limited as most cells are relatively small due to reliance of the diffusion of substances in and out of cells
What is rate of diffusion affected by?
- The amount of surface area available
- Temperature
- Concentration gradient
- Distance
What is surface area-to-volume ratio?
- Organisms made of many small cells have an advantage over organism composed of fewer, larger cells.
- As cell size increase, volume increase much more rapidly than its surface area.
- Some cells overcome limitation by being long and narrow
Why do we use microscopes?
Not many cells are visible to the naked eye. as most cells are less than 50 micrometers.
The resolution function on microscopes allow the minimum distance between two points can be apart but still be distinguished as two separate points.
What are the types of microscopes?
Light microscopes and electron microscopes?
Which microscope do you use for atoms?
electron microscope
Which microscope do you use for amino acids & proteins?
electron microscope
Which microscope do you use for red blood cells?
electron or light microscope
Which microscope do you use for mitochondria?
electron or light microscope
Which microscope do you use for chloroplast?
electron or light miscoscope
Who proposed Cell Theory?
Schleiden and Schwann
What is the visual scale for microscopes and naked eye?
<100 nanometer = electron microscope
1nm-100nm = light microscope
>100 micrometer = Human eye
What characteristics do all cells have?
- Nucleoid or nucleus where DNA is located
- Cytoplasm that has semifluid matrix of organelles and cytosol
- Ribosomes that synthesize proteins
- Plasma membrane made up of phospholipid bilayer
What are the simplest organisms?
The two domains of prokaryotes:
Archaea and Bacteria
What do simplest organisms have and don’t have?
1.They lack a membrane bound nucleus.
2.DNA present in nucleotide.
3.Cell Wall is outside of plasma membrane.
4.Have ribosomes.
There are no organelles common to all prokaryotes.
True
What are bacterial micro-compartments?
Cellular compartments bounded by a semipermeable protein shell. (40 - 400nm)
What are the functions of BMCs?
Isolate specific metabolic processes and storage.
What is peptidoglycan?
A form of polysaccharide.
What is most bacterial cell walls composed of?
Peptidoglycan
What are fungi cell walls composed of?
Chitin
What are plant walls composed of?
Cellulose
What is the function of a cell wall?
- Protect the cell
- Maintain shape
- Prevent excessive uptake or loss of water
What do arcane cell walls lack?
Peptidoglycan, however make it up in diversity of components like protein and saturated hydrocarbons + glycerol.
What is flagella?
Present in prokaryotic cells that are used for locomotion that rotates to propel cell forward.
What are eukaryotic cells?
Eukaryotic cells possess a membrane-bound nucleus and are more complex than prokaryotic. They also posses a cytoskeleton.
What is eukaryotic noted by?
Compartmentalization = has many compartments because of membrane bound organelles and endromembrane system.
What is the endomembrane system?
A series of membranes throughout cytoplasm that divides cells into compartments where different cellular functions occur.
What is the main difference between eukaryotes and prokaryotes?
One of the fundamental distinctions between eukaryotes and prokaryotes is that eukaryotes have an endomembrane system.