Intro To Cell Biology Flashcards
Cell
-The basic microscopic unit of all living beings
-Cell produces energy and use it to build necessary substances
Cell Theory
1-All organisms: one or more cells
2-Cell is structural unit of life
3-Cells arise only by division from a pre-existing cell
Cell
Smallest unit to exhibit life
Cells from different species
Share Similar structure, composition, and metabolic features have been conserved throughout evolution
Genetic matter
1- Information is packaged into a set of chromosomes
2-Genes store information
3- All cells contain identical copies of DNA
Cellular Reproduction
Reproduce by division, a process which the contents of mother cell are distributed into two daughter cells
Energy
Photosynthesis provides fuel
Energy is product of photosynthesis mainly in form of glucose
Glucose convert to ATP -> readily available energy
Sum total of the chemical reactions
Cell’s metabolism
Cell’s activity
1- Transport Materials
2- Assemble and disassemble structures
3- Move itself
For example: Motor protein
Cell respond to stimuli
Receptors interact with substances in the environment
Cell respond by:
1- Altering the metabolism
2- Moving from one place to other
3- Committing suicide
Self Regulation
Feedback circuits serve to return the cell to appropriate state
Cellular factors function
Spontaneous by DNA genome program
Evolution
All living organisms evolved from a single, common ancestral cell named LUCA
not the first life on earth but first that still have living descendants
Prokaryotic and eukaryotic similarities
1- Identical genetic language
2- Common metabolic pathways
3- Common structural features
What limits the size of a cell?
1- Maintain adequate local concentrations
2- Adequate surface area relative to volume
3- Rates at which molecules can diffuse
Surface area is important why?
Exchange between the cell and its surroundings take place there
Cell volume is important why?
Amount of exchange that is needed
Model organisms compartment
1- Simple organisms
2- Fast generation time
3- Large numbers of offspring
4- Easy to manipulate
5- Inexpensive to breed
How prokaryotic and eukaryotic cell are distinguished?
By their:
1- Size
2- Organelles they contain
Hypothesis
Statement consistent with most of the data
Theory
Hypothesis that has been extensively tested
Law
Theory that has been tested and confirmed over a long time period and no doubt of its validity
Virus
An infectious agent that can only replicate inside a living cell
Virus compartment
Nucleic acids (DNA & RNA) enclosed in protein coat
