Micro #2 Flashcards
Heterotrophs
From organic source
Such as glucose
Autotroph
Inorganic source
Like C02
An organism that grows in lower pH conditions is called
Acidophile
The phase of bacterial growth curve in which the rate of multiplication equals the rate of cell death is the
Stationary growth phase: The population enters survival mode. The cells stop working or grow slowly. Rate of growth equals rate of death
Phototroph
Theirs source of energy is light
Chemotroph
Chemical compounds
Photoautotrophs
Use carbon dioxide as a carbon source and light energy to make their own food
Chemoautothrophs
Use carbon dioxide as carbon source but catabolize organic molecules for energy
Photoheterotrophs
Acquire energy from light and acquire nutrients via catabolism or organic compounds
Chemoheterotrophs
Use organic compounds for both energy and carbon
Saprobic Microorganism
Some bacteria and fungi hace rigid cell wall and cannot engulf large particles of food
Parasitic Microorganisms
Considered Pathogens
They can cause damage to the tissues and cause death
Ectoparasites
Live on the body
Endoparasites
Live in organs and tissues
Intracellular Parasites
Live within cells
Obligate Parasites
Unable to live outside of living host
Passive transport
Transport of nutrients in a gradient
From higher density to lower density concentration
Does not use ATP
Diffusion
Movement of molecules in a gradient
From higher density to lower density
Osmosis
The movement of water across a selectively permeable membrane
Facilitated difffusion
Utilizes carrier proteins
Will bind to a specific substance
Hypotonic
Solute concentration is lower than the cells internal environment
Hypertonic
Environment outside the cell had a slightly higher concentration of solutes than inside the cell
Osmotic pressure forces water to diffuse out of the cell
Active transport
Transport of nutrients agains the diffusion gradient
Could be same direction of gradient but faster
Group translocation
Molecule is moved across the membrane and simultaneously converted to a metabolically useful substance
Bulk transportation
Mass transport of large particles, cells and liquids bu engulfment and vesicle formation
Organisms that live on dead animals and plans and digest food by secreting enzymes are called________
1) Saprobes
2) Commensals
3) Parasites
4) Autotrophs
1)Saprobes
Which type of solution will result in water entering the cell?
1) Hypertonic
2) Hypotonic
3) Isotonic
4) All of the above
2)Hypotonic
Microorganisms that have a requirement for growth below 15 degrees celcius are called________
1) Mesophile
2) Psychrotrophs
3) Thermoduric
4) Psychrophiles
4)Psychrophiles
Obligate aerobes
Oxygen is an absolute necessity for their survival and growth
Obligate anaerobes
Cannot tolerate the presence of oxygen
Will die in presence of oxygen
Facultative Anaerobes
Can survive with or without oxygen
Usually show higher growth in presence of oxygen
Aerotolerant aerobes
Anaerobes that do not use oxygen but can grow in it’s presence
Microaerophiles
Do not grow at atmospheric oxygen concentrations
They require small amounts of oxygen
They can only live in conditions where there is reduced oxygen concentration
Thioglycollate Broth
It’s a medium that absorbs some of the oxygen present
Creates an oxygen gradient
Aerobic at the top
Anaerobic at the bottom
Neutrophiles
Microorganisms that grow at neural pH
Alkalinophiles
Microorganisms that prefer to grow in an higher pH
Osmophiles
Microorganisms living in habitats with high solute concentration
Symbiosis
When two organisms live together in a close partnership
Mutualism
When organisms live in an obligatory but mutually beneficial relationship
Commensalism
The relationship benefits one member but not the other
Parasitism
The host provides the parasitic microbe with nutrients and a habitad
The parasite looks to multiply
Usually causes harm to the host
Association of symbiotic organisms
Mutualism
Commensalism
Parasitism
Association of Non-symbiotic organisms
Synergism
Antagonism
Synergism
Members cooperate and share nutrients
Antagonism
Some members are inhibited or destroyed by others
What is the most common method for microbial reproduction?
Binary fission
Lag phase
The start
There is no growth
Exponential growth phase
There is growth reaching peak
Stationary phase
The growth is equal to death
Death phase
Cell growth is less than death rate
Which phase of growth has limited nutrients and exponential death of cells?
Death phase
Exist when organisms live in an obligatory but mutually beneficial relationship
Mutualism
The time required by the bacteria to double
Generation time
Newly inoculated cells require a period of adjustment
Lag phase
An organism that uses CO2 for its carbon needs and sunlight for its energy needs would be called a_________
Photoautotroph
Bacteria living in a freshwater stream that are transferred to acne water would______
Become dehydrated due to the loss of water
The methanogens, produces of methane gas, require environments that_________
Are anaerobic with hydrogen gas and CO2
An organism with a temperature growth range of 45°C to 60°C would be called a(n) ______.
Thermophile
The phase of the bacterial growth curve that shows the maximum rate of cell division is the ______.
Exponential phase
Use carbon dioxide as a carbon source but catabolize organic molecules for energy.
Chemoautotrophs
Acquire energy from light and acquire nutrients via catabolism of organic compounds.
Photoheterotrophs
Catabolism
The breaking down of large molecules into smaller molecules
Anabolism
The building of larger molecules from smaller molecules.
Catabolic activities produce energy in the form of ATP that can then be used in anabolic reactions.
Can enzymes be regulated?
True
False
True
What are enzymes composed of?
1) Fats
2) Sugars
2) Proteins
3) DNA
4) All of the above
2)Proteins
What is the job of the enzymes?
Enzymes help reactions occur more quickly by lowering the amount of energy required for the reaction to occur
Enzymes_________ the activation energy
1) Increase
2) Lower
2)Lower
Factors affecting enzyme activity
Temperature - As temperature increases so the reaction rate
Concentration of catalyst - More enzymes increase reaction rate
Concentration of reactants
pH
Which one of the following does NOT affect enzyme activity?
1) Temperature
2) Number of active sites
3) pH
4) Concentration of reactants
2)Number of actives sites
What does holoenzyme mean?
Complete and functional enzyme
What are holoenzymes made out of?
Apoenzymes
&
Any required coenzymes/cofactors
Oxidoreductases
Involved in oxidation/reduction reaction
E.g Lactate dehydrogenase & Oxidase
Substrates: Pyruvic acid & Molecular Oxygen
Catalyzes the conversion of pyruvic acid to lactic acid
Catalyzes the reduction of O2
Transferases
Transfer functional groups
E.g. DNA polymerase
Substrate: DNA Nucleosides
Synthesizes a strand of DNA using the complementary strand as a model
Hydrolases
Cleave bonds with the addition of water
E.g Penicillinace & Lactase
Substrate: Penicillin & Lactose
Hydrolyses beta-lactam ring
Breaks lactose down into glucose and galactose
Lyases
Add or remove groups without the addition of water
Isomerase
Change the isometric for
Ligases
Form bonds with the addition of ATP and removal of water
Exoenzyme
Enzyme outside the cell
How are most enzymes produced?
Via gene transcription and translation
Constitutive enzymes
Always present within a particular cell type
Present in relatively constant amounts
Regulated Enzymes
These enzymes are turned ON or OFF depending on substrate concentration within the cell
Feedback inhibition
A process in which the final product in the reaction will feedback to shit down the metabolic pathway
Competitive Inhibition
A molecule that mimics the shape of the substrate, binds to the active site and prevents the normal substrate from binding
Non-competitive inhibition
A molecule will bind to a site on the enzyme that is outside of the active site
This binding causes the enzyme to change its 3D shape
So the active site is no longer functional
The original substrate is unable to bind to the enzyme
When enzyme action stops due to a buildup of end product that acts as a regulatory molecule, this control is called ______.
Non-competitive inhibition
The formation of peptide bonds between amino acids to build a polypeptide is an example of ______.
Anabolism
A ______________ is an organic molecule needed to form a holoenzyme.
1) ATP
2) Coenzymes
3) Cofactors
4) Vitamins
2)Coenzymes
The binding site for the substrate is the __________________.
Active site
Increasing the amount of the enzyme will increase the ___________.
Reaction rate
Binding of the substrate to the enzyme produces a/an _____________ complex.
Enzyme/substrate complex
An __________________ will slow down or stop enzyme activity.
Inhibitor
A _________________mimics the shape of the substrate.
Competitive inhibitor
When a molecule regulates the activity of an enzyme by binding to a site outside of the active site, it is known as a/an __________________.
Non-competitive
Enzymes lower the __________________.
Activation energy
__________is the sum of all the chemical reactions that take place in an organism
Metabolism
During aerobic cellular respiration, the final electron acceptor is ______.
1) Oxygen
2) Cytochrome C
3) Pyruvic Acid
4) Nítrate
5) FAD
1)Oxygen
The overall chemical equation for cellular respiration is___________
C6H12O6 [glucose] + 6 O2 = 6 CO2 + 6 H2O + ATP
When glucose is broken down by glycolysis during bacterial fermentation, what is the usual net production of ATP?
2
Fermentation
The incomplete oxidation of glucose
It is an inefficient way to produce ATP
The Krebs cycle is important for the catabolism of the three macromolecules____________
1) Carbohydrates
2) Proteins
3) Fats
In bacterial cells, the electron transport system is located in the ______.
Cell membrane
The formation of citric acid from oxaloacetic acid and an acetyl group begins ______.
The Krebs cycle
Oxygen reacts with hydrogen to produce ______________in the electron transport chain.
Water
As the electron transport carriers shuttle electrons, they actively pump _____ into the outer membrane compartment, setting up a concentration gradient called the proton motive force.
Hydrogen ions
The reactions of fermentation function to produce _______ molecules for further use in glycolysis.
NAD+
During anaerobic respiration a common final electron acceptor is _____.
NO3
In the cell, energy released by electrons is often used to phosphorylate ______.
ADP
who developed the gram stain?
Hans
What color does gram positive stain?
Purple
What color does gram negative stain?
Red/Pink
Why does bacteria stain differently?
Because of their cell wall structure
Gram positive has a thicker wall so it retains the purple color after being washed with the iodine
Gram negative is not capable of retaining the color so it stains with the secondary dye
What are viruses?
- Viruses are miniscule, acellular, infectious agents that use the host’s machinery for replication
- Packaged in a protein called capsid
- Obligate intracellular parasites
Viroids
Non-cellular agents
Smaller than viruses
Are infectious RNA strands
Prions
Non-cellular agents
Smaller than viruses
Are infectious Proteins
Host cells of viruses include:
a) Humans & other Animals
b) Bacteria
c) Protozoa and Algae
d) Plants & Fungi
e) All of the choices are correct
e)All of the choices are correct
Viruses are:
a)Acellular infectious agents Have DNA or RNA as genetic material b)All of the statements are correct c)Can infect bacteria or eukaryotes d)parasitic microorganisms
b)All the statements are correct
What does virus in latin mean?
Poison
Who identified the unique characteristics of viruses?
The unique characteristics of viruses were first identified by Ivanovski and Beijernick
Extracellular virions
- Have capsids (Nucleocapsids)
- Some have a phospholipid envelope
Intracellular virions
The capsid is removed and the virus exists as nucleic acid
Capsid
- Provides protection
- Means of attachment to host cell
What’s an enveloped virus?
Viruses with a phospholipid bilayer envelope
Whats a naked virus?
These lack coverage like the envelopes
Some viruses have virally coded __________ (spikes) that playa role in recognition and attachment to a host
Glycoproteins
Bacteriophage
The type of virus that invades bacteria
Mycophage
The type of virus that invades Fungal cells
