Replication
Origin of replication: sequences of
nucleotides in the DNA that are rich in AT bases because A and T only have 2 hydrogen bonds hence it's easier to break the bonds.
Helicase breaks the
hydrogen bonds, so
double helix can Separate
Topoisomerase:
Relieves the strain
or tension of the
strands so the rep.
fork won't break
Primase
creates an
RNA primer
that goes in
the replication
bubble
DNA pol III
synthesizes the new
polymer of DNA
Then DNA Pol I
replaces the RNA primers
with DNA nucleotides
synthesizes in 5' to 3'
direction; adds nucleotides
in 3' end. Needs and OH
group @ 3' end to replicate
Ligase Seals all
the gaps/fragments
by joining nucleotides
with Phosphodiester
Bonds
SSB: prevents
the DNA helix
from forming
again after
helicase forms
the bubble.
PCR: Replication in LABS.
DNA is used as a Primer and
instead of DNA pol II, Taq Pol
is used.
Transcription
Promoter sequence of
nucleotides where RNA
pol binds to start transcription
in prokaryotes.
RNA pol binds to promoter;
synthesize RNA in 5' to 3'.
The product is mRNA
In eukaryotes, Trnascription factors,
bind to the promoter(TATA Box), then
which makes RNA pol III to attacth to
promoter= Transcription Initiation Complex. This synthesize pre-mRNA
Then a Poly-A signal of AAUU
makes ribonuclease cut pre-mRNA
to stop transcribing.
A cap( Guanini+ 3 Phosphate)
is added to the 5' end.
Poly A polymerase adds A's
on 3' end which becomes
the poly A tail.
After synthesis of
pre-mRNA. it's time
for RNA processing.
Eukaryotic genes are
split into segments:
introns inegrated among
exons. In RNA spicing
introns are removed by
spliceosome. This allows
for alternative splicing.
Translation
First, small
ribosomal subunit binds
to cap and recognizes the
start codon on the mRNA; Then, the big
ribosomal unic comes and
also binds. This occurs @
cytoplasm
Then tRNA synthase attaches
to tRNA. Then the tRNA comes
attaches to the p site on the big
ribosomal unit.
Then another tRNA
comes on A site. The
1st tRNA on P site moves
to E site and leaves. While
the 2nd moves to P site
forming a peptide pond is
formed btwn the amino acid
on P site
This continues till we
see a stop codon; a
stop codon means stop
translating.
With the the help of
release factors, everything
dissociates and.
Depending on the signal,
the polypeptide will stay
to free ribosomes and go
to certain organelles like
mitochondria; Or it will go
to bound ribosomes/ER due
to the signal
The start codon
for Prokaryotes
is f- Met; while in
eukaryotes is
Met
Mutations: Error
in DNA when a gene
is altered or changed
which changes the
genetic message
Silent Mutation:
a change in base;
but doesn't change
the amino acid
Missense Mutation:
Changes Amino Acid
Nonsense Mutation:
Stops translation really
early.
FrameShift Mutation:
Adding or deleting a
base which creates
a shift in the mRNA;
However, if 3 are added
or deleted that doesn't
change. Since one codon
has 3 amino acids
prokaryotic cells: most are unicellular and have circular DNA
Bacteria: most typically unicellular and contain peptidoglycan plasma membranes
archae bacteria: it can live in harsh conditions
Extremophiles: bacteria that can live in extreme conditions.
Thermophiles: bacteria that can live in very hot environments, such as volcanoes.
Acidophiles: bacteria that can live in very acidic environments, like sulfur geysers
Halophiles: bacteria that can live in extremely salty environments; for example salt lakes.
Endospore: prokaryotes form them when living in harsh condition that can't really thrive in them.
Endosymbiotic Theory. Theory that explains why the mitochondria and chloroplast have circular DNA and double membrane. They were engulfed by a 'host' cell that now helps and be came dependent on each other to function.
Eukaryotic Cells
unicellular
mutlicelluar
animal
plant
Photosynthesis
Light reactions
Photosystem II
Photophosphorylation:
ATP is made
Photosystem I
NADPH COMPLEX: makes NADPH
Calvin Cycle
Carbon Fixation:
CO2 IS FIXED INTO 3C
Reduction:
6 ATP AND 6 NADH are used, 1 G3P Molecule is used
Regeneration:
3 ATP are used
Glucose is made
Transduction and Communication
Cell Junctions
Plasmodesmata
microscopic channels which traverse the cell walls of plant cells and some algal cells, enabling transport and communication between them
Gap
Allow the exchange of ions, second messengers, and small metabolites between adjacent cells
Desmosome
Intercellular junctions that provide strong adhesion between cells
Tight
Where membranes of 2 cells join forming a barrier virtually impermeable to fluid.
Cell signaling: Communication
that governs basic activities of
cells and cordinates cell actions
Local
Synaptic: A nerve
cell releases neurotransmitter
molecules into synapse
Long Distance
Endocrine: specialized
endocrine cells secrete
hormones into body fluids
Hormone travels in bloodstream
but a target cell specifically binds to hormone
Ion Channels
A gate opening or
closing the channel
when receptor changes shape
A ligand binds to receptor and
the channel opens, ions flow
through the channel. When ligand
dissociates from receptor, the channel closes
GPCR
Reception
Ligand binds to GPCR
this causes the G-protein
to attach to GPCR
Then, G protein
replaces GDP w/ GTP
Transduction
G protein w/
GTP binds to
enzyme, Adenyl Cyclase
This activated Adenyl Cyclase
converts ATP to cAMP
CAMP activates protein Kinase A
The protein kinase A adds a phosphate
to another protein= phoshphorylation cascade
This amplifies a signal to Transcription Factors
Response
Transcription
Factors finish
the cellular
response
Tyrosine-Kinase
Reception
2 signalling molecule
bind to 2 receptor which
causes the receptor to
form a dimer
The activate Tyrosine
on both Receptors add
phosphates to another
Now, the TKR binds
to relay proteins
This triggers
transduction
leading to celllular Response
Intracellular Reception
The receptors are
found inside the cell
The hydrophobic molecules
like hormones pass the
membrane and bind to
receptor inside the cell
The hormone-receptor
complex enters nucleus
and does it's pathways
Energy
endergonic-absorption of energy
Photosynthesis
Light-dependent reactions
ATP
NADH
Calvin cycle
Glucose
exergonic-release of energy
cellular respiration
Glycolysis
2 pyruvate
2 NADH
2 ATP
Krebs cycle
6 NADH
2 ATP
2 FADH
electron transport
Water
34 ATP
NAD and FAD
Functional Groups
Hydroxyl
OH
Carboxyl
C-OH
Carbonyl
C-O
Sulfhydryl
S-H
Phosphate
P-OH
Amino
NH3
Solutions/Molarity
Conservative: keeps
the original stand and
creates a new strand
Semiconservative:
Produces both old
and new; each DNA strand contains
once complete old and new
strand. THE CORRECT MODEL
In the experiment
after centrifugation
We see a band at the
middle(Hybrid density)
and at top(light density)
*EXACTLY LIKE THE
SEMICONSERVATIVE
MODEL*
Nucleotide
Phosphodiester bond
A, G, C, T
DNA
Nucleoside
Sugar and a Base
Monosaccharides
Glucose
Fructose
Galactose
Glycerol
Fatty acids
Saturated
Unsaturated
Cis
Trans
sperm
egg
SMOOTH ER: detoxifies cell, adds
ROUGH ER: protein secrete cells, and packages into transport vesicles for export.
Nucleolus: ribosomes and rRNA are made.
Extra Cellular Matrix: In Eukaryotes
a network of proteins and carbohydrates that binds cells together.
Surrounds and supports the cell.
regulates cell activities.
lattice for cell movement
Membrane Proteins
Active transport:
Low to high concentration with the help of a membrane protein and input of energy.
Passive transport
Diffusion:
high to low concentration, nonpolar molecules can pass through
Facilitated diffusion:
high to low concentration with the help of a membrane protein.
Osmosi:
when H2O moves over to balance solutes that cannot pass the cell membrane.
Cytoskeleton: main functin is to help transport and maintain shape of cell.
Mircotubulin
Made up of alpha and beta-tubulin.
It helps line up Chromosomes during mitosis and Meiosis
Maintains Shape of cell
Helps transport vesicles
Cell motiiity
Actin Filaments
made up of actin
Along with Mysoin(enzyme), it creates muscle contractions.
Maintain cell shape
Cytoplasmic streaming
Cell Divison:
it helps aid in dividing the cell when the cleavage furrow occurs.
Changes in cell shape
cell motility
Intermediate filaments
made up of multiple proteins. (ex: kinases)
Maintains cell shape
anchorage of nucleus and certain other organelles
Formation of nuclear lamina
free
make proteins
bound
Contractile Vacuole: contracts depending on the molarity of the solution outside of the cell.
NH3
CHCl3
NaCl
Polar
H2O
Nonpolar
CH4
Pepsin
Bleach
Number and arrangement of multiple folded protein subunits in a multi-subunit complex
Sequence of amino acids in the polypeptide chain
When the polypeptide chains fold into regular structures like the beta sheets, alpha helix, turns, or loops
Hydrogen-bonds between different side chain groups
An oncogene arises
from a genetic change that leads
to increase in proto-oncogene's
protein product or in the activity
of each protein molecule
Movement of DNA within the GENOME
Amplification of Proto-oncogene
Poing mutations in a control elements
Mutation that reduces
the activity of its protein
product may lead to
excessive cell division and cancer
Where the concentration of solutes is greater outside the cell than inside it
Flaccid
Cell becomes shriveled
Plasmolyzed
The cytosol and plasma membrane shrinks because H2O is coming out of the cell
A solutions that has less salt and more solute and more water than another solution
Lysed
More H2O is coming in than going out so Cell can burst, become lysed.
Turgid
More H2O is coming in than going out.
Where concentration of the solutes is the same both inside and outside of the cell
Normal
H2O is coming in and out constantly creating an equilibrium.
Flaccid
H2O is coming in and out of the cell, but it's not the normal state for plant cells because then they don't retain water that is needs to support their functions.
OH
CH3
Krebs cycle:
main purpose is to make NADH AND FADH, a net total 6 NADH, 2 ATP, snd 2 FADH. IN INNER-MEMBRANE OF MITOCHONDRIA
Oxidative phosphorylation:
26-28 ATP. IN MITOCHONDRIA MATRIX
Electron Transport Chain: Electrons are transported through out protein complex I, III, & IV. NADH AND FADH2 are used.
Chemiosmosis:
Protein complexes are pumping H+ ions across the membrane to create a concentration gradient, in order for H+ ions to go through ATP synthase to make ATP.
Fermentation
Lactic acid
ethanol