TEST 2; 7-9 & 11+12
parenteral
(systemic action, delivered by routes other than the GI tract; i.e. non oral). - Action may be topical (local) or systemic
Glycolysis overall gives rise to these products
2 NADH, 2 ATP and 2 three-carbon compound
Which of the following help(s) to stabilize mRNA by inhibiting its degradation?
5' cap and poly (A) tail
Ethyl alcohol is maximally effective at
70%
All living things require
C, H, O, P, K, N, S, Ca, Fe, Na, Cl, Mg but the relative amounts vary depending on the microbe
Which out of the following does not generate ATP
Calvin Cycle
Which statement about bacterial cell walls is false?
Cell walls prevent cells from dying in hyper tonic conditions.
Zn
Cofactors for enzymes
Death Phase
Curve dips downward; cells begin to die at an exponential rate
Which enzyme catalyzes the elongation of a DNA strand in the 5' → 3' direction?
DNA polymerase III
Osmosis
Diffusion of H2O thr' a selective permeable membrane; when membrane is b/w solutions of differing conc and the solute is not diffusible, water will diffuse from more water side to less water side
Adaptations to Osmotic Variations in the Environment Example: fresh pond water- Bacteria- Amoeba-
Example: fresh pond water- hypotonic conditions Bacteria- cell wall protects them from bursting Amoeba- a water (or contractile) vacuole that moves excess water out of the cell
Saprobes and what wall cell do they have/ decomposers of what
Free-living microorganisms; feed primarily on organic matrix of dead organisms Decomposers of plant litter, animal matter, and dead microbes; most have rigid cell wall, so they release enzymes to the extracellular environment to digest food particles
Which of the following has the greatest amount of energy for the cell: REMEMBER that glucose can produce 30 -32 ATP in prokaryotes/eukaryotes respectively.
Glucose
What happens to glucose and oxygen in cellular respiration
Glucose gets oxidized and oxygen gets reduced
Which is most abundant in cell- H20; Which is most abundant in a cell in dry condition- protein
H20 in cell protein in dry condition
Nutrients are categorized according to C content inorganic and organic:
Inorganic nutrients: a combination of atoms other than C and H Organic nutrients: contain C and H, usually the products of living things
What is the effect of a nonsense mutation in a gene?
It introduces a premature stop codon into the mRNA.
Phosphorus
Key component in nucleic acids and also found in ATP
Phototrophs (food)
Microbes that photosynthesize
Heterotroph: Must obtain C ininorganic /organic form (nutritionally dependent on other living things)
Organic and dependent other living things)
Hypertonic
Outside solute conc is higher than inside cell /cytoplasm; will force water to diffuse out of a cell as said to have high osmotic pressure
Hypotonic
Outside solute conc is less than inside cell; net direction of osmosis is from the hypotonic solution into the cell; cells without cell walls swell and can burst
Photoauto(self)trophs
Photosynthetic- Cyanobacteria,algae plants
Replication in prokaryotes differs from replication in eukaryotes for which of these reasons?
Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have many.
Which of the following is true for both prokaryotic and eukaryotic gene expression?
RNA polymerase binds to the promoter region to begin transcription.
Lag Phase
Relatively "flat" period; newly inoculated cells require a period of adjustment, enlargement, and synthesis The cells are not yet multiplying at their max rate Length of lag period varies from one population to another
Each of the following options is a modification of the sentence THECATATETHERAT. Which of the following is analogous to a frameshift mutation?
THECATATTHERAT
What is meant by the description "antiparallel" regarding the strands that make up DNA?
The 5' to 3' direction of one strand runs counter to the 5' to 3' direction of the other strand.
active site-
The catalytically reaction
Isotonic
The environment has same solute conc as cell's internal environment; no net change in cell volume; most stable environment for cells
Stationary Growth Phase
The population enters a survival mode in which cells stop growing or grow slowly The rate of cell inhibition /death balances out rate of multiplication; depleted nutrients and oxygen Excretion of organic acids and other biochemical pollutants into the growth medium
Macronutrients
The six key elements that organisms need in relatively large amounts: play principal roles in cell structure and metabolism (ex. C, H, N, O)
Autotroph
Uses inorganic CO2 as its carbon source (not nutritionally dependent on other living things)
Exponential Growth (Log) Phase
When the growth curve increases geometrically; cells reach the max rate of cell division; will continue as long as cells have adequate nutrients with favorable environment
Turbidometry procedure
a tube of medium becomes turbid as microbes grow in it; either transmission or absorbance of light is measured which are opposite to each other; A=2-log %T
Amoeba
a water (or contractile) vacuole that moves excess water out of the cell
Halobacteria living in the Great Salt Lake
absorb salt to make their cells isotonic with the environment
Micronutrients
aka trace elements, smaller amounts and involved in enzyme function etc. ex. Mn, Zn, Ni
which contains nitrogen,in addition to carbon, oxygen, and hydrogen?
an amino acid such as glycine
Essential Nutrient
any substances that must be provided to an organism (e.g essential aa and essential FA-3 from fish for human); also called growth factor
What is the basis of bacterial population growth:
binary fission
hydrocarbons not soulbule in water.
bonds are non polar covalent to caron
Na and K
certain types of cell transport and membrane function
The ionic bond of sodium chloride is formed when
chlorine gains an electron from sodium
zinc in active site works as
cofactor (metals)
-NITROGEN
component in proteins, DNA, RNA. Why not other macromolecules ??
Mg
component of chlorophyll
Sulphur
component of some vitamins and amino acids e.g. Met & Cys
Enumeration
counting the number of cells in a sample microscopically with use of a special microscopic slide (cytometer)
Plant-like photosynthesis that releases O2 occurs in
cyanobacteria.
Kreb cycle in a prokaryotic cell occurs
cytoplasm
Parasites (obligate saprobe)
derive nutrients from the cells or tissues of a host; also called pathogens b/c they cause damage to host's tissues
polymers with monomer-
dna/nucleotide
nitrogen is much more electronegetive than hydrogen . which of the following statements is correct about atoms
each hydrogen has partial positive charge.
Chemohetero (other) trophs
eat others; protozoa, fungi, many bacteria and many animals
Obligate saprobes
exist strictly on dead organic matter in soil and water
What are the coding segments of a stretch of eukaryotic DNA called?
exons
Assuming that each of these possesses a cell wall, which prokaryotes should be expected to be most strongly resistant to plasmolysis in hypertonic environments?
extreme halophiles
Antibiotics are meant only for treatment, thus these NEVER result in superinfections in body even though by their inappropriate use.
false
A Molecule with C18H36 is probaly a
fatty acid
The most versatile method of sterilizing heat-sensitive liquids is
filtration
These organisms are saprobes
fungi
Chemotrophs
gain energy from chemical compounds
which is not a polymer-
glucose
Polymyxin antibiotic work against
gram neg
Polymyxins
gram negative bacteria
Which of the following separates the DNA strands during replication?
helicase
Example high salt environment
hypertonic conditions
fresh pond water
hypotonic conditions . Bacteria cell wall protects them from bursting:
Fe
important component of cytochrome proteins
Phospholipids
in cell membranes
Penicillin group acts by
inhibiting cell wall synthesis
Sulpha drugs act by
inhibiting folic acid synthesis
Is H2O and CO2 are organic or inorganic compounds ?
inorganic
Steriliant will be able to :
kill all microbes including endospores
Endoparasites
live in organs and tissues;
Ectoparasites
live on the body;
Intracellular parasites
live within cells;
Pathogenic bacteria to humans are mostly:
mesophiles
Common routes of administration-
oral (enteral) and non oral/parenetral (i.v, im etc). Oral/enteral (delivered through the GI tract),
Enzymes involved in cell respiration are _____ in nature NOTE: SELECT ALL VALID ANSWERS
organic compounds, are made of amino acids bonded together, proteins.
co2 is released during
oxidation of pyruvate to acetyl CoA and the citric acid cycle
Hydrogen
performs overlapping roles in cell biochemistry: Maintaining pH Forming hydrogen bonds between molecules Serving as the source of free energy in Redox Rxn
A relative flat portion of bacterial growth curve refers to:
period of adjustment and enlargement etc
Which of the following are responsible for high levels of O2 in Earth's atmosphere?
photoautotrophs
Which is the bacterial structure that acts as a selective barrier, allowing nutrients to enter the cell and wastes to leave the cell?
plasma membrane
Ideal drug of choice be
selective toxic to bacteria harbored in host body
Most antibiotics are isolated from soil organisms includingi
some bacteria and fung
Ca
stabilizer of cell walls and endospores
Obligate anaerobe
strictly requires O2 absence otherwise it can die exposed to O2
What determines the nucleotide sequence of the newly synthesized strand during DNA replication?
the nucleotide sequence of the template strand
Generation or doubling time
time required for a complete fission cycle from parent cell to two new daughter cells
Russian physicians are currently using bacteriophages
to treat bacterial infections...
Glutaraldehyde is a sporicidal agent.
true
Penicillin has beta lactam ring, so bacteria which develop resistance for this drug secrete beta-lactamase enzyme
true
Obligate parasites
unable to grow outside of a living host