week 1 Flashcards
Central Dogma
DNA—>RNA—>Protein
Molecules of life
Macrmolecules
Carbohydrates- polymers of sugar
Lipids- not polymers
proteins- polymers of amino acids
nucleic acid- polymers of nucleotides
Resolution
the ability of a microscope to distinguish two objects as being separate
higher magnification increases resolution
contrast helps with detail but cant increase resolution
Microscopy types
Light 1.reflected light 2.transmitted light 3.fluorescence Electron 1.transmission 2.Scanning
Darkfield
Contrast-enhancing methods
Illuminates sample at an angle so light does not hit the objective lens directly
only light that is scattered upwards by the sample reaches the objective lens
Phase contrast
- Variations in specimen thickness and refractive properties how light passes through it
- This method creates slight phase shifts in the illuminating light, which manifest as higher detailed images
Fluorescence
- electrons absorbs a photon and gets excited to a higher energy state
-Excited electron returns to its ground state, releasing a photon of longer wavelength
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Transmission electron microscopy
beam of electrons is transmitted through an extremely thin section of a specimen. Best resolution of the internal organization of cells and their organelles
Cytoplasm
- Consists of cytosol+organelles
- cytosol is aqueous liquid
- full of macromolecules + smaller molecules
- metabolic activities
- signal transduction
Ribosomes
- highly organized machine consisting of proteins and rRNA. Its actually more like an enzyme than an organelle
- reads the sequences of mRNA to coordinate their translation into proteins
- (Ribo- Ribonucleic acid) + (Som-body)
- prokaryotic ribosomes are a bit smaller but do the same thing
Cytoskeleton
- Filamentous polymers that partcicipate in many processes
- cell division
- intracellular transport
- intracellular organization and shape
- present both prokaryotes and eukaryotes
- prokaryotes have ancient versions
Prokaryotes
unicellular small no membrane bound organelles nucleoid single circular chromosomes+plasmids
Eukaryotes
unicellular or multicellular large to very large membrane bound organelles nucleus linear DNA in chromosomes
Green Fluorescent Protein
single molecule dynamics
whole cellular behaviour
whole organ growth and hormone physiology
Smooth ER
Synthesizes lipids, phospholipids and steroids
not abundant in most cells
highly abundant in cells that secrete the above molecules
also abundant in cells involved in detoxification of drugs and alcohol
Lysosomes
like the stomach (acidic breaks things down)
hydrolyses. both internal and external things
autophagy
found primarily in animals
Vacuoles
storage of nutrients
turgor pressure for cell enlargement
maintain ion gradients
digest waste products
Mitochondria
The source of all cellular respiration which creates the bulk of the cells energy in the form of ATP
Chloroplast
Performs photosynthesis
two boundary membranes + internal thylakoid membrane
stroma is the cytoplasm
stacks of thylakoids are called grant
photosynthetic reactions occur in thylakoids and storm
chromoplast
Amyloplast
Proteinoplast- protein storage sites
Chromoplast- house pigements for organ coloration
amyoplast- contain starch for energy storage some specialized ones in root tips and soem stems are used to sense the direction of the gravity vector for gravitropism
proteinoplast- protein storage sites
Microtubules
polymers of a/b tubular dimers
13 protofilaments
have plus and minus ends which gives them an inherent polarity
frequent switches between growing (polymerization) and shortening (depolymerization)
most growth/shortening occurs at plus ends
Centrosomes
plasma membrane
outer limit of cytoplasm responsible for the regulation substances moving into and out of cells
DNA
deoxyribonucleic acid
large double stranded helical molecule that contains the genetic material of all living organisms
glycocalyx/capsule
carbohydrate coat covering the cell surface
cell wall
rigid external layer of material surronding the plasma membrane of cells in plants, fungi, bacteria, and some protists, providing cell protection and support
nucleus
central region of eukaryotic cells, separated by membranes from the surronding cytoplasm where DNA replication and messenger RNA transcription
nucleoid
central region of prokaryotic cell with no boundary membrane seperating it from cytoplasm, where DNA replicationand RNA transcription occur
organelle
the nucleus and other specialized internal structures and compartments of eukaryotic cells
plasmid
DNA molecule in the cytoplasm of certain prokaryotes which often contains genes with functions that supplement those in the nucleoid and can replicate independently of the nucleiod DNA and be passed along during cell division
flagellum
a long threadlike cellular appendage responsible for movement found in both prokaryote and eukaryotes but with different structures and locomotion
cyanobacteria
colony
scanning electron microscope
detailed 3 dimensional image of the surface of the specimen. Used for intact specimens such as insects and pollen grains
confocal laser scanning microscopy
type of fluorescence microscopy that involves focusing a laser light source onto a very thin plane. Used to examine specimens that are too thick to be examined with fluorescence microscopy
