Cellular & Molecular Biology Flashcards
Polymer degradation
Hydrolysis. Adds a water molecule breaking a bond.
Light microscopy
To visualize whole cells and large sub-cellular organelles.
E.g nucleus and chromosomes
Electron microscopy
Use electromagnets to focus a beam of electrons through specimen or onto its surface.
Transmission Electron microscopy
To study internal cell structure
E.g organelles proteins and nucleus acids
Does this by beam through specimen
Scanning Electron Microsopy
To study cell surface and generate 3D images
Focus a beam onto the surface of specimen
Prokaryotic cells
Nucleoid
Where DNA is concentrated
Describe the internal structure of prokaryotic cells
Little or no internal structure or organelles
Name and describe the main features of a prokaryotic cell
Plasma membrane: encloses cytoplasm Cell wall: rigid structure Capsule: jelly like coating Fimbriae: attachment to other bacteria Flagella: locomotion
Describe the nucleus in eukaryotic cells
Have a nucleus that contains most of the cells DNA
What do eukaryotic cells have that prokaryotic cells don’t
Cellulose cell wall: Protects cell and maintains shape
Central vacuole: storage and breakdown of waste products
Chloroplasts: photosynthesis
Cell organelles
Nucleus
Nucleolus Chromatin fibers Inner membrane Outer membrane Nuclear pores Connect to rough ER
Cell organelles
Endoplastic reticulum and ribosomes
Smooth ER Rough ER ER lumen Cisternae Ribosomes bound to ER Free ribosomes in cytosol
Cell organelles
Golgi apparatus
Cis face (receiving end)
Vesicles from ER > Golgi
Cistern all maturation move cis to teams direction
Vesicles leave Golgi carrying specific proteins
Cell organelles
Lysosomes
Carry active hydrolytic enzymes
Used to digest food or breakdown damaged organelles
Fuses with vesicle
Hydrolytic enzymes digest food particles/organelle components
Cell organelles
Mitochondria
Outer membrane Inner membrane Cisternae Matrix Free ribosomes in matrix Respiratory enzymes in inner membrane and matrix
Cell organelles
Chloroplast
Only in plants and algae
Site of photosynthesis
Thylakoids
Stacked = granum
Cytoskeleton
Maintain cell shape Facilitate cell movement Facilitates movements within cell Three types: Micro tubules Micro filaments Intermediate filaments
Micro tubules
Protein: tubulin
Function: cell shape
Organelle + chromosome movement
Motility
Micro filaments
Protein: actin
Function: change in cell shape
Cell division
Contraction
Intermediate filaments
Protein: keratin
Function: anchorage of nucleus and organelles
Cell fractionation
Isolates cell components based on size and density through centrifugation
Macromolecules
Polymers constructed of identical or similar building blocks called monomers
Types of macro molecules
Lipids
Polysaccharides
Proteins
Nucleic acids
Lipids
Hydrophobic Water insoluble Function: energy storage Structural molecules Hormones
Polysaccharides
Function: energy storage
Structural molecules e.g cellulose, chitin
Carbohydrate residue can be joined to proteins or lipids
Storage of polysaccharides in plants
Starch.
Polymers of glucose monomers
Polymer assembly
Dehydration. Removes a water molecule forming a new bond
