Scorpio's Section Flashcards
how do bacteria reproduce?
via binary fission
what is generation time?
length of time required for a single bacterial cell to yield 2 daughter cells
what influences generation time for bacteria?
genetics & environmental factors
Bacterial growth undergoes 4 phases. Name each and describe them.
1) Lag phase: time when bacteria gathers the essential constituents in order to replicate.
2) Log phase: they replicate in exponential numbers
3) Stationary phase: no longer are increasing in #, plateau phase.
4) Decline phase: cell death is exponential. bacteria reproduced beyond nutrients provided by the agar so they die.
what is turbidity measurements?
its not sensitive; the extent of cloudiness is equivalent to the extent of bacterial cells. more cloudiness= lots of bacteria. no cloudiness= no bacteria.
What is Real-time PCR?
counting the # of bacterial cells in a sample quantified based on the detection of [DNA]. this technique is fast and accurate.
When it comes to bacterial nutrition, what kind of “-trophs” are they? And what does the name mean?
chemoheterotrophs- uses organic chemicals as sources of energy & carbon
Bacterial nutrition: most bacteria requires ____ & ____ in relatively large amounts.
carbon & nitrogen
In culture media what is the main source of nitrogen for bacteria?
peptones
What are three other things that bacteria require to grow in a medium?
phosphates, sulphates, & trace elements
What are growth factors?
these are essential substances required for biosynthesis
Growth of bacteria in culture is influenced by 5 things.
1) temperature
2) hydrogen ion concentration
3) availability of moisture
4) atmospheric composition
5) osmotic pressure
Definition: organisms with an optimum growth near 37 degrees C (body temp)
mesophiles
Definition: organisms with an optimum temp beween 45 - 70 degrees C
thermophiles
definition: archaea with an optimum T of 80 degrees or higher
extreme thermophiles or hyperthermophiles
definition: cold-loving organisms that can grow in a fridge
psychrophiles
Bacteria require ____ for growth, and species vary widely in their susceptibility to desiccation.
water
Bacterial cells in the environment are usually present in ____ solutions. In ____ solutions, bacterial cells undergo shrinkage.
hypotonic; hypertonic
Metabolism has an energy- generating component called _____.
catabolism
Metabolism has an energy-consuming component called _____.
anabolism
_____ rxns produce energy as ATP.
catabolic
_____ is energy temporarily conserved in “high energy bond”
ATP
What are the two ways cells can fundamentally produce ATP?
1) substrate level phosphorylation
2) electron transport phosphorylation
Simple: via glucose & respiration
Heterotrophic metabolism is driven mainly by two metabolic processes: ____ & _____.
fermentations & respirations
Describe in general glycolysis.
uses glucose to generate 2 ATP, 2 NADH, & 2 pyruvates which is used in cellular respiration
In fermentation all ATP are produced by ____ _____ _____.
substrate level phosphorylation
Fermentation of Ethanol, ____ (specific ex) uses this under anaerobic condition and it creates a net gain of ___ ATP.
Yeast; 2
Fermentation of Lactate Slide: Many organisms will also ferment pyruvic acid into, other chemicals, such as ____ ____.
lactic acid
Respiration processes such as Kreb’s cycle & Electron Transport occur in the ____ of eukaryotes & the ____ in prokaryotes.
mitochondria; cytoplasm
In the transition reaction to Kreb’s cycle, what is produced?
acetyl Co-A
How is ATP made in the process of oxidative phosphorylation?
ADP is reduced by a gain of electrons –> ATP!
How many ATP in total are made is Oxidative phosphorylation?
38 total
In what part of the cell does the electron transport system occur?
plasma membrane
Definition: study of genomes of organisms
genomics
Definition: entirety of an organism’s genetic info
genome
Definition: a segment of chromosomal DNA that codes for functional products
gene
Define exon.
segment of gene that codes for useful things
Define intron.
segment of gene that doesnt encode anything, useless.
A bacterial cell possesses a ____ chromosome of a ____ circular molecules of DNA with associated proteins.
both blanks: single
DNA is anti-parallel,what does that mean?
the DNA run in opposite directions
____ are the basic structural units of nucleic acids (DNA & RNA).
Nucleotides
What is the MAIN difference between RNA & DNA?
RNA has uracil & DNA has Thymine
What are 2 purines?
adenine & guanine
What are 2 pyrimidines?
Cytosine & thymine
Each strand of DNA has a ____ consisting of alternating sugar & phosphate groups
backbone
A ____ base is attached to each sugar in the backbone of DNA.
nitrogenous
Where on the helix can you find the sugar-phosphate backbone? (outside or inside)
on the inside
The backbone of DNA can be thought of as the ____ of a ladder, whereas the bases in the middle form the ____ of the ladder.
sides; rungs
Definition: this contain info that is transcribed from the DNA, and it is single stranded molecule complementary to DNA.
mRNA
Defnition: Transfer genetic info
tRNA
Definition: Components of ribosome
rRNA
What is the ‘central dogma’ of genetics?
DNA –> transcription –> RNA –> translation –> polypeptides subunits (proteins)
___ have closed, circular DNA.
bacteria
What are the most important things you have to know about the replication fork?
1) unzip DNA
2) then RNA polymerase & DNA polymerase come along which put the single RNA strand w/ the DNA strand
3) then it an encode w/ the entrons which can make proteins
What are the 3 ways in which RNA & DNA differ?
1) RNA is single stranded (DNA has double)
2) RNA has ribose sugar (DNA has deoxyribose)
3) Base pairing -A-U
(A-T pairing for DNA)
what is the purpose of tRNA?
transfers amino acids to ribosomes for protein synthesis
what is the initiation-start codon for translation?
AUG
What terminated translation?
a stop codon
What are the 3 types of mutation? describe each
- silent mutation: mutation the miraculously make a normal protein
- missense mutation: makes a faulty protein
- nonsense mutation: makes an incomplete protein
