Chapter 1 Flashcards
State the cell theory
1- all living organisms are composed of cells
2- cells the the smallest basic unit living structure of life
3- new cells are formed by previous cells diving - omnis cellula e cellula
Schleiden and virchow
1 and 2 - scheildon
3- virchow
Describe the properties of cells
1 - autonomous 2- internally regulated 3- organized 4- self regulating 5- respond to stimuli 6- capable of movement 7- acquire and use energy 8- reproduce themselves 9- perform chemical reactions 10- self replication collection of catalysts
Describe cell as a system
A cell is a system of connected organelles and structures that work together
It also shows emergent properties
State the central dogma and explain
1- info flows from DNA to RNA to Proteins
It means that the genes in DNA provides instructions for making a protein , which is then copies by the RNA , RNA uses the instructions to make proteins. Proteins perform the function and are responsible for the function , form and behaviour of cells and organism
What are the exceptions to the central dogma
1- the flow of info is different in the virus . The info moves from DNA to RNA eg in retrovirus due to reverse transcription when virus is inside the host
2- there are more than one type of RNA eg tRNA , rRNA and mRNA however only mRNA is transcribed .
3- there are also non coding RNA types eg microRNA
EVOLUTION TREE :-
What is the ancestral cell
Prokaryotic cell
Ancestral cell is divided into
Bacteria and archea
Describe bacteria category
2 types of bacteria
1- non photosynthetic bacteria
2- photosynthetic bacteria
Describe the category of archea
Archea gave rise to SINGLE CELLED EUKARYOTIC CELLS when mitochondria (Bactria) was adapted into the cells
Single cell eukaryotic cells lead to animal, fungi and archea and plants ( this happened after another bacteria ( chloroplast was adapted inside the single celled eukaryotic cells )
Whats the evidence that eukaryotes arose from ancestral archea
Due to the structural similarities in eukaryotes, archea and bacteria
Structure =—————
Fubction
What does the rule structure = function gives rise to ? Explain
Diversity of cells
Because structure = functions , there are many different functions in the cell , organelle or organism therefore each function has a different structure of cells therefore it gives rise to diversity
How do we study cells ?
A- we approach cell biology with a REDUCTIONIST VIEWPOINT ( it is based on the premise that studying the part of a whole can explain the character of the entire organism
- The cells is similar to a working machine with many parts
- knowing how the ind parts work can explain the whole
- understanding how cells work can reveal so much about the nature of life
What is system biology
Computational and mathematical modelling of complex biological system that will eventually allow for the engineering of biological system
Cell area and volume ?
A - 4#r2
V- 4/3#r3
When cells get bigger the SA/V ration———-?
Decrease
This causes? Explain
Reduction in SA causes
1- decrease in efficiency of movement of molecules
2- decrease in efficiency of absorbing nutrients
3- difficulty in getting rid of wastes
Explanation
When the D of a cell-is 1 um , it takes 100 millisecond to diffuse oxygen , however when the D increases to 10um , it takes 10 million times longer
Cells are usually measured in
Um = 10^-6
Nm=10^-9
Whats the mag and res of light microscope
Max Mag = 2000x
Res = 100nm
Types of light microscope
1- Differential interference contrast microscope
2- Fluorescence microscope
- confocal fluorescence microscope
Describe the fluorescence microscope
This uses a fluorescence dye that absorbs certain wavelength and emits a longer wavelength
What is the max magnification and res of electron microscope
Mag - 10 million
Res - 1nm
Types of electron microscope and explain
Sem - shows the surface of dead cells
Uses metal lining
Tem - shows the cross section of dead cells
Uses metal lining
