Samenvatting
whole summary cell biology
- Instelling
- Vrije Universiteit Amsterdam (VU)
this is a whole summary of all the cell biology lectures.
[Meer zien]Voorbeeld 3 van de 30 pagina's
Voorbeeld 3 van de 30 pagina's
In winkelwagengesponsord bericht van onze partner
Voorbeeld van de inhoud
Whole summary cell bioLecture 1 Essential Cell Biology
The cell
essential features
- contains biomolecules (e.g protein/RNA/DNA)
- is an autonomous unit in performing a function
- can respond & adapt to stimuli
- can (often) reproduce itself
The basic ingredients of the cell
- DNA: deoxyribonucleic acid the language of genes
o Conserved within all known cells
- 3d structure: double helical structure
o Protects against damage
o Allows double copy for repair
- proteins: form code to function
Tree of life: bacteria, archaea & eukaryotes
- prokaryotes: cells without organelles, have structure by complexes instead of organelles
o Bacteria : no nucleus or other organelles
o Archaea : no nucleus, often extremophiles
- Eukaryotes : nucleus and other organelles, sometimes multicellular life forms
the power of the lens HOTTIE <3
- Microscope: invented by Antonie van Leeuwenhoek (1632-1723)
- Talented glassworker, made microscopes with one lens with pin and candle
How do they work
- light source
- falls through couple of lenses
- condenser lens: made sure that light from lamp is concentrated on specimen
- objective: rotated to change magnification and focus
- eye piece: determines end magnification
- eye: will also effect magnification
Advanced light microscopy: fluorescence microscopy
- instead of all light, filter used to only use one
colour of photon
- light is reflected onto object
- reflecting protein is bit longer wavelength, looses a bit of energy
- can specifically look at proteins labelled with specific tag
GFP: green fluorescent protein
- Cloned from: Jellyfish: important for attracting mates, uses blue light to interact with GFP
- Using GFP, you can visualise subpopulations of cells in tissue and living cells in multicolour
,The resolution of EM (electron microscopy)
- Hardly any wavelength
How does an EM work?
- Electron gun: same as light but will radiate electrons
- Radiate into a beam onto the slide by condenser lens
- Contrast natural elements with heavy metals: more protons more
positive charge to deflect electrons
- Can not use colour: are scattered away or absorbed: electron
- We can not see electrons: use chemicals to make electrons emit green light: visible
- Microscope used under vacuum
LM vs EM
- Advantage of EM over LM:
o Superior resolution (up to 0.5 nm!, atoms!)
o Visualise the whole cell, not only a fluorescent probe (e.g. GFP).
o Huge magnification range (30x-300.000x: 104)
- Disadvantages of EM compared to LM:
o requires fixation of cells (operates under vacuum).
o Only small pieces of tissue can be imaged.
o Time-consuming method
Summary 1: cells & microscopes
- A cell is a compartment containing biomolecules (DNA, RNA, protein) that are surrounded by
membrane and can react to stimuli.
- All cells have the same basic ingredients but show huge diversity in shapes and functions
- To study the form-function relationships, microscopes are essential:
o Light microscopy
o Fluorescence microscopy
o Electron microscopy
eukaryotes
The nucleus
- Denser part: nucleolus
o Darker DNA: a lot used,
- Lighter part: chromatin stored in cell, euchromatin: used a lot
- Tightly coiled: used less
- Nuclear envelope: membrane around nucleus, protects DNA
- Nuclear pore: promotes inside outside environment
- Scaffold proteins: only found during metaphase of cell cycle
Translation of RNA to protein in the endoplasmic reticulum (ER)
- ER: looks like fishnet of connecting tubes and sheets, lot of membrane
- Continuous lumen
, What does the Golgi apparatus do?
- protein modification & protein sorting
o Modulate 3d shape by modifying different sugar chains
o Come in at cis site, gets out at trans site
o Trans Golgi network: sorting of proteins
▪ Go to different organelles
▪ Outside world
▪ Membrane: receptors
- Man: mannose - Gal: galactose
- GlcNAc: n-acethylglucosamine - NANA: N-acetylneuraminic acid
The mitochondrion: energy supply
- Double membrane: wrapped not only inner part but forms cisternae inside, increase PM
- Burning glucose yields energy in the form of (ATP) by krebs cycle
- Mitochondria contain own DNA: bacteria: symbiotic relationship
The chloroplast: energy supply in plants photosynthesis
- Used to be bacteria: symbiosis
- Plants still need mitochondria to burn the glucose provided by in photosynthesis.
Cytoplasm
- cytoplasm is not fluid, but a jelly matrix of proteins and subcellular compartments
processes of the cytoplasm
- transport
- protein synthesis
- protein break-down
- signal transduction
- membrane fusion
- ionic homeostasis
form and transport: the cytoskeleton
- intermediate: cross links and cross interacting, organelles
- actin: dynamics, quick changes
- microtubule: main structure of cell
Summary 2: organelles
- Cells in the tree of life comprise bacteria, archaea and eukaryotes.
- Only eukaryotes contain organelles and a nucleus, can form multicellular organisms
- The basic organelles and their function:
o The nucleus: store DNA and transcription of DNA to RNA.
o The endoplasmic reticulum: translation of RNA to protein and protein folding.
o Golgi apparatus: post-translational modification and sorting of proteins.
o Mitochondrion: energy supply in the form of ATP
o Chloroplast: photosynthesis
o Cytoskeleton: cell shape and transport
o Cytoplasm: multifunctional protein gel and homeostasis
Voordelen van het kopen van samenvattingen bij Stuvia op een rij:
Verzekerd van kwaliteit door reviews
Stuvia-klanten hebben meer dan 700.000 samenvattingen beoordeeld. Zo weet je zeker dat je de beste documenten koopt!
Snel en makkelijk kopen
Je betaalt supersnel en eenmalig met iDeal, creditcard of Stuvia-tegoed voor de samenvatting. Zonder lidmaatschap.
Focus op de essentie
Samenvattingen worden geschreven voor en door anderen. Daarom zijn de samenvattingen altijd betrouwbaar en actueel. Zo kom je snel tot de kern!
Veelgestelde vragen
Wat krijg ik als ik dit document koop?
Je krijgt een PDF, die direct beschikbaar is na je aankoop. Het gekochte document is altijd, overal en oneindig toegankelijk via je profiel.
Tevredenheidsgarantie: hoe werkt dat?
Onze tevredenheidsgarantie zorgt ervoor dat je altijd een studiedocument vindt dat goed bij je past. Je vult een formulier in en onze klantenservice regelt de rest.
Van wie koop ik deze samenvatting?
Stuvia is een marktplaats, je koop dit document dus niet van ons, maar van verkoper jill3. Stuvia faciliteert de betaling aan de verkoper.
Zit ik meteen vast aan een abonnement?
Nee, je koopt alleen deze samenvatting voor €4,99. Je zit daarna nergens aan vast.
Is Stuvia te vertrouwen?
4,6 sterren op Google & Trustpilot (+1000 reviews)
Afgelopen 30 dagen zijn er 52510 samenvattingen verkocht
Opgericht in 2010, al 14 jaar dé plek om samenvattingen te kopen