Midterm exam Flashcards
(80 cards)
1
Q
What is microbiology?
A
The study of microorganisms or microbes. (organisms too small to be seen w/o a microscope).
2
Q
Define Microorganisms
A
Microscopic organisms (commonly called germs, viruses, agents, etc.) but not all cause diseases. many are usesful and essential for human life.
3
Q
Describe the types of microorganisms.
A
Bacteria, fungi, protozoa, virus, and archaea
4
Q
What are common human uses of microorganisms
A
food production, medicine, waste treatments, research, agriculture
5
Q
Basic cell structure of bacteria/archaea and eukaryotes
A
plasma membrane, cytoplasm , and ribosomes
6
Q
Differences between bacteria/archaea and eukaryotes
A
The key difference is that bacteria and archaea are prokaryotes. (no nucleus and membrane bound organelle).
7
Q
Lifestyles of microorganisms
A
found nearly everywhere
occur in large amounts
live in places many other organisms can’t
8
Q
Who was the founder of microbiology?
A
Antoni Van Leeuwenhoek
9
Q
Spontaneous generation famous experiment
A
abiogenesis- theory that life came from non-living matter
10
Q
Germ Theory of Disease
A
Koch, Pasteur proved that pathogens cause infectious diseases which is the germ theory of disease. Etiology is the study of the causation of diseases.
11
Q
Key definitions, such as pathogen, sterile, aseptic, anoxic
A
pathogen - causes disease
sterile- abense of microorganisms
aseptic- medically clean, free of pathogens
Anoxic-environments or processes without O2
12
Q
How do we name microorganisms / taxonomy
A
. problem w/common names - vary w/ regions
2. microbial nomenclature - naming microorganisms
3. identification - discovering and recording the traits of organisms so they can be named and classified
4. levels of classification - divide from most broad to most specific
13
Q
Key chemistry definitions (e.g. matter, atom, proton, neutron, electron, nucleus,
element, atomic mass, isotope, atomic number, compound/molecule, reactants,
products, solutions)
A
Matter-
atom-
Proton-
Neutron-
Electron-
Nucleus-
Element-
Atomic mass-
Isotope-
Atomic number-
Compound Molecule-
Reactants-
Products-
Solutions
14
Q
Why do orbitals matter for elemental bonding?
A
The shape and orientation of an atoms orbitals determine how they can overlap with the orbitals of other atoms, creating necessary conditions for a chemical bond to form.
15
Q
Name and describe and provide examples of the 3 major types of chemical bonds
A
Ionic bond- the transfer of one or more electrons between a metal and nonmetal. A metal gives electrons to a nonmetal.
Covalent-The sharing of electrons between to atoms.
Metallic- Similar to covalent- a way that metal atoms are kept together within a metal material.
16
Q
Properties of solutions
A
vapor pressure, depression, bioloing point elevation, freezing point depression, osmotic pressure.
17
Q
pH scale understanding
A
ranges from 0-14
7=neutral=pure water
Less than 7= acidic=lemon juice
Greater than 7=basic alkaline Ammonia
18
Q
What is an organic molecule?
A
Most carbon containing molecules that are present in all living organisms. (example Nucleic acids, glucose, and amino acids)
19
Q
List and describe the 4 biological macromolecules
A
Carbohydrates-stored energy- composed of carbon, hydrogen, oxygen, glucose, cellulose.
Lipids-water proof membranes, energy storage, fats oils
Proteins-molecular machines, act as enzymes, built from amino acids as building blocks
Nucleic acids- store and transfer genetic information(DNA and RNA).
20
Q
Protein structure
A
3D arrangements of atoms in a protein molecule formed by a chain of amino acids folded into a specific shape, important for functions of the body.
21
Q
Describe the difference between DNA and RNA
A
DNA is double stranded molecules, and RNA is single stranded. DNA contains the sugar deoxyribose, whereas RNA contains ribose. DNA uses thymine and RNA uses Uracil.
22
Q
What is ATP?
A
(Adenosine Triphosphate) is a molecule that provides energy for cells. Found in all living cells. needed to make RNA and DNA.
22
Q
5 I’s of microbiology – names and descriptions
A
Inoculation
Incubation
Isolation
Inspection
Identification
23
Q
Definition of fastidious microbes
A
microbes that require an enriched media to grow.
23
Media classification
its based on the composition of nutrients, the presence of absence of O2. (Simple or basal media)
24
Most commonly used media
liquid media or nutrient broth
25
Key characteristics of a light microscope and relevant definitions/calculations
The body or head comprises the optical parts present in the upper part of the microscope.
The arm connects and supports the base and head of the microscope. ...
Base of the microscope supports the microscope and comprises the illuminator.
26
Simple stains and negative stain
Simple staining
Uses a positively charged dye to directly stain bacterial cells. This technique is often used to distinguish between yeast and bacterial cells, or to check for contaminants.
Negative staining
Uses a negatively charged dye to stain the background of a smear, leaving the bacteria unstained. This technique is often used when viewing samples with an electron microscope
27
Fimbriae
thin, hair-like protein structures that extend from the surface of bacterial cells, primarily functioning to enable bacteria to adhere to specific surfaces or host cells, essentially acting as a mechanism for attachment and colonization; often considered crucial for bacterial virulence in pathogenic bacteria
28
Major structural features of a bacteria cell AND their use
In bacteria, the cell wall forms a rigid structure of uniform thickness around the cell and is responsible for the characteristic shape of the cell (rod, coccus, or spiral).
29
Pilus
30
Gram Positive Cell Wall features
fimbriae. hair-like appendages on the surface of many bacteria and archaea that help with bacterial adhesion, colonization. and infection
30
Flagellum
A bacterial cell functions as a motility organelle, it is responsible for propelling the bacteria through its environment by rotating a filamentous structure that acts like propeller.
31
Gram Negative Cell Wall features
In the Gram-negative Bacteria the cell wall is composed of a single layer of peptidoglycan surrounded by a membranous structure called the outer membrane. The gram-negative bacteria do not retain crystal violet but are able to retain a counterstain, commonly safranin, which is added after the crystal violet
32
Cytoplasm
The cytoplasm protects the cell's organelles and genetic material from damage caused by movement and collisions with other cells. The cytoplasm maintains the cell's shape and structure. It also gives specific locations for different organelles, such as the nucleus and centrosome, which are often found at the center of the cell.
33
Ribosomes
In a bacterial cell, ribosomes function as the primary site for protein synthesis, translating the genetic code from mRNA into amino acid chains to build proteins essential for the cell's activities; essentially acting as the "protein factory" within the cytoplasm, reading the mRNA sequence and assembling the corresponding amino acids to create new proteins.
34
Nucleoid
The nucleoid functions much like the nucleus in eukaryotic cells in that it is the regulatory center of the prokaryotic cell. This region regulates the growth, reproduction, and function of the prokaryotic cell.
35
Plasmid
A plasmid is a small, circular, double-stranded DNA molecule that is distinct from a cell's chromosomal DNA. Plasmids naturally exist in bacterial cells, and they also occur in some eukaryotes. Often, the genes carried in plasmids provide bacteria with genetic advantages, such as antibiotic resistance.
36
Inclusions
Non-living components: Unlike organelles, inclusions are non-living substances within the cytoplasm.
No membrane bound: Inclusions are not enclosed by a membrane, unlike most organelles.
Storage function: Their primary role is to store excess nutrients, pigments, and other cellular products for later use.
37
Bacterial shapes - especially Coccus, Bacillus, Spirillum
Coccus- round, spherical bacteria, often seen in clusters or chains depending on the species
Bacillus- A rod-shaped bacteria, appearing as elongated cylinders
Spirillum- A spiral-shaped bacteria, with a helical structure
37
Bacterial colonies and biofilms – key features
37
Flagella structure and arrangement
Bacterial flagella are a coiled, thread-like structure, sharp bent, consisting of a rotary motor at its base and are composed of the protein flagellin. A shaft exists between a hook and a basal body passing through the protein rings in the cell membrane.
38
Chemotaxis and phototaxis, run and tumble
"Chemotaxis" refers to the movement of an organism towards or away from a chemical stimulus, while "phototaxis" refers to movement in response to light; "run and tumble" is a specific type of movement pattern often seen in bacteria during chemotaxis, where they alternate between swimming in a straight line ("run") and randomly reorienting themselves ("tumble") to navigate towards a chemical gradient.
39
Form and function of Fimbriae and Pili
Fimbriae and pili are extensions of the cytoplasmic membrane and are made up of an oligomeric protein known as pilin. They are hair-like appendages present on the bacterial cell wall similar to flagella. They are involved in bacterial conjugation, attachment to the surface and motility.
40
Form and function of Glycocalyx
The glycocalyx is a gel-like, fuzzy coating on the outer surface of a cell membrane, composed of a network of glycoproteins and glycolipids, which acts as a protective barrier, facilitating cell-cell recognition, adhesion, and signaling, while also playing a crucial role in regulating vascular permeability and protecting the endothelial lining of blood vessels in animals.
41
Biofilm formation
Biofilms are a complex, multistep process where microorganisms attach to surfaces and form a 3D structure that protects them from the external environment:
42
Features and function of Gram positive and gram negative cell envelopes
Gram-negative bacteria are surrounded by a thin peptidoglycan cell wall, which itself is surrounded by an outer membrane containing lipopolysaccharide. Gram-positive bacteria lack an outer membrane but are surrounded by layers of peptidoglycan many times thicker than is found in the Gram-negatives.
43
Peptidoglycan and its role in cell walls
Peptidoglycan is a crucial component of bacterial cell walls, primarily responsible for maintaining the cell's shape, rigidity, and protecting it from osmotic pressure by acting as a strong, mesh-like structure;
44
Gram stain procedure
The Gram stain procedure was developed in 1884 by Danish scientist Hans Christian Gram.Prepare the slide: Place a fixed smear of the sample on a microscope slide.
Apply crystal violet: Flood the slide with crystal violet stain and wait 15 seconds. Rinse with water.
Apply iodine: Flood the slide with Gram's iodine and wait 15 seconds. Rinse with water.
Decolorize: Apply a decolorizer, such as ethanol or acetone, to the slide. Rinse immediately with water.
Counterstain: Flood the slide with safranin and wait 15 seconds. Rinse with water.
Blot and dry: Blot the slide with absorbent paper and allow it to air dry.
View: Examine the slide under a microscope using oil immersion to achieve 1000X magnification.
Record results: Record the results based on your laboratory's criteria
45
Functions of cytoplasmic membrane
The cytoplasmic membrane protects the inner components of the cell. It also acts as a barrier providing selective permeability for importing nutrients and exporting wastes. It is also where some energy production takes place.
46
Why and how endospores form (life cycle) and germinate
ndospores form as a survival mechanism for bacteria, particularly when faced with unfavorable environmental conditions like nutrient deprivation, allowing them to remain dormant and highly resistant to extreme heat, radiation, desiccation, and chemicals until conditions improve, at which point they can germinate and return to an active vegetative state
47
Describe the theory of endosymbiosis
The endosymbiotic theory explains the evolution of eukaryotic cells from the first prokaryotic cells. The theory states that the first prokaryotic cells entered a mutualistic relationship with other prokaryotic cells (endosymbionts) that gave rise to its organelles.
48
Where do archaea live?
Archaeans include inhabitants of some of the most extreme environments on the planet. Some live near rift vents in the deep sea at temperatures well over 100 degrees Centigrade. Others live in hot springs (such as the ones pictured above), or in extremely alkaline or acid waters.
49
How did eukaryotes go from single cellular to multicellular?
In eukaryotes, DNA in cells is wrapped tightly around proteins called histones, which, in turn, are packed together into a structure known as chromatin.
50
What is a saprobe?
. an organism, esp a fungus, that lives on decaying organisms
50
Describe the external, cell boundary, and internal cell features of Eukaryotes and
their major functions
A eukaryotic cell is characterized by a distinct external boundary called the plasma membrane, a well-defined nucleus enclosed by a nuclear membrane, and a complex internal structure containing various membrane-bound organelles like mitochondria, Golgi apparatus, and endoplasmic reticulum, all suspended in the cytoplasm; essentially, the key feature of a eukaryote is its organized, compartmentalized internal structure with a true nucleus.
51
What are the 2 basic microscopic morphology of fungi
The two basic microscopic morphologies of fungi are yeasts (single-celled) and hyphae (filamentous, thread-like structures) which form a network called mycelium; essentially, fungi can appear as either unicellular yeasts or multicellular hyphae.
51
Which eukaryotic organisms are always unicellular, may be uni- or multi-cellular,
and always multicellular
Eukaryotic organisms that are always unicellular are typically classified as protists, which include organisms like amoeba, paramecium, and most unicellular algae, while organisms that can be either unicellular or multicellular include some types of algae and fungi depending on the species.
52
What is the potential link between microbes, weather, and the Salem Witch Trial?
bad bread may of caused the trial and cool weather
53
What are some examples of microbes in Kingdome Protista
Examples of microbes in Kingdom Protista include: algae, amoebas, euglena, plasmodium, slime molds, diatoms, dinoflagellates, red algae, and protozoa; essentially, any single-celled eukaryotic organism that isn't classified as a plant, animal, or fungus falls under Protista.
54
What are cysts with regard to protozoa?
cysts are a dormant, resting, or resistant stage in the life cycle of many protozoa.and are often encased in a protective membrane or thickened wall. Cysts are a survival mechanism for protozoa, allowing them to survive in unfavorable environmental conditions and disperse the species.
55
Pasteur’s role in virology
French mircobiologist who made discoveries related to viruses including rabies, germ theory of disease, vaccines, pasteurization, silkworm diseases
56
How did scientists know about viruses before we could view them with advanced
microscopic methods?
The first evidence of the existence of viruses came from experiments with filters that had pores small enough to retain bacteria
57
Why is virology a relatively new field?
Virology is considered a relatively new field because it was only established in the 20th century. Here are some reasons why: lack of methods,filterable, composition, visualization
58
Structure and function of viruses
A virus is a microscopic particle composed of a nucleic acid genome (either DNA or RNA) enclosed within a protein shell called a capsid, and some viruses also have an additional lipid envelope; its primary function is to infect a host cell and use the host's machinery to replicate and produce more viruses by delivering its genetic material into the host cell.
59
Suffix for virus families and genera?
virus families is -"Viridae"
Virus genera is-"virus"
60
What is a bacteriophage? What does it look like?
A bacteriophage, often called a "phage" for short, is a virus that specifically infects and destroys bacterial cells; visually, it often resembles a tadpole or spaceship-like structure with a head (containing the genetic material) and a tail used to attach to and inject its DNA into a bacteria cell, making it look like a tiny robot under a microscope.
61
Name the 6 general phases in the life cycle of animal viruses and a brief
description of the phase
Attachment:
The virus binds to specific receptors on the surface of the host cell, which is crucial for the virus to infect the correct cell type.
Penetration:
Once attached, the virus enters the host cell through different mechanisms depending on the virus type, like fusion with the cell membrane (for enveloped viruses) or endocytosis (engulfment by the cell).
Uncoating:
Inside the host cell, the viral capsid is removed, releasing the viral genome which is now ready to be replicated.
Replication:
The viral genome directs the host cell's machinery to synthesize viral components like proteins and nucleic acids, using the host cell's enzymes and nucleotides.
Assembly:
The newly synthesized viral components come together to form new virions, including the capsid encapsulating the viral genome.
Release:
62
Define Prion and give one example
A prion is a type of protein that can trigger normal proteins in the brain to fold abnormally.Prion diseases can affect both humans and animals. They are sometimes spread to humans by infected meat products.
63
Define ecosystem, communities, populations, abiotic, biotic, and trophic
Ecosystem:
A community of living organisms (biotic factors) interacting with their non-living physical environment (abiotic factors) within a specific area, including factors like temperature, water, soil, and sunlight; essentially, all the living and non-living components in a particular place working together as a system.
Communities:
A group of different species of organisms living in the same area and interacting with each other, only considering the living components of an ecosystem.
Populations:
A group of individuals belonging to the same species that live in the same area and can interbreed with each other.
Abiotic:
Non-living components of an ecosystem, such as rocks, air, water, temperature, and sunlight.
Biotic:
Living components of an ecosystem, including plants, animals, bacteria, and fungi.
Trophic:
Referring to the feeding level of an organism within an ecosystem, where producers (plants) are at the first trophic level, herbivores at the second, and carnivores at higher levels.
64
What are biomes, habitats, and niches?
Biome:
A large-scale category like a desert, rainforest, or grassland, defined by its dominant vegetation and climate.
Habitat:
A smaller area within a biome where a specific species lives, like a tree hollow for a bird or a coral reef for a fish.
Niche:
The functional role an organism plays in its habitat, including its diet, behavior, and interactions with other species.
65
Describe the terms autotroph, heterotroph, primary consumer, higher order consumers, detritus feeders/decomposers.
Autotroph- an organism that can produce its own food using sunlight or chemical energy.
Heterotroph- An organisms that must consume other organisms to obtain energy.
Primary consumers- all animals, fungi, and many bacteria are considered heterotrophs; also called "consumers"
higher order consumers- Organisms that eat other consumers, positioned further up the food chain; secondary consumers eat primary consumers, tertiary consumers eat secondary consumers, and so on.
Detritus feeders/decomposers- Organisms that break down dead organic matter, recycling nutrients back into the ecosystem; includes bacteria, fungi, and certain invertebrates like earthworms.
65
What are the 6 most abundant elements associated with life
carbon,hydrogen, nitrogen, oxygen,phosphorus, and sulfur
66
List the 1st and 2nd principles of ecosystem sustainability
First Principle. For sustainability, ecosystems use sunlight a non-depleteable non-polluting form of energy.
Second Principle. For sustainability, ecosystems break down and recycle all wastes as nutrients.
67
What happens to nutrients and energy in natural ecosystems
In natural ecosystems, energy flows in a one-way direction from the sun, through producers (plants), to consumers (animals), and eventually dissipates as heat, while nutrients cycle through the ecosystem, being taken up by plants, passed through consumers, and returned to the environment by decomposers, allowing for continuous reuse within the system.
68
What are key roles of mycorrhizae?
Nutrient uptake: Mycorrhizae increase the plant's ability to absorb nutrients, especially phosphorus, which is often in short supply in natural soils.
Water storage: Mycorrhizae can store water and nutrients for use when rainfall is scarce.
Disease resistance: Mycorrhizae help plants resist infection from fungi and bacteria.
Tolerance to adverse conditions: Mycorrhizae can help plants tolerate drought, high temperatures, salinity, acidity, and toxic elements in the soil.
Soil structure: Mycorrhizae help improve soil structure by interacting with organic matter and breaking down rock.
Nutrient cycling: Mycorrhizae play a role in cycling nutrients like phosphorus, nitrogen, carbon, and micronutrients, which enhances soil fertility.
Underground communication: Some research suggests that plants can communicate with each other through shared mycorrhizal networks.
69
How do microbes play a role in global change:
Microbes play a significant role in global change by driving crucial biogeochemical cycles, particularly in the production and consumption of greenhouse gases like carbon dioxide and methane, which directly impact climate change; they do this through processes like decomposition, nitrogen fixation, and by influencing the carbon storage capacity of soils and oceans depending on environmental conditions.
70
Permafrost
As permafrost thaws, it releases stored carbon that microbes can use for respiration or the production of CH4 through methanogenesis. These actions can create a positive-feedback loop that increases carbon levels in the atmosphere.
71
Animal agriculture
Microbes play a significant role in global change within animal agriculture primarily by influencing the production and release of greenhouse gases, particularly methane, through their decomposition of organic matter in animal waste, which contributes significantly to climate change; additionally, microbes in the gut of livestock can impact digestion efficiency and nutrient uptake, potentially affecting the overall environmental impact of animal agriculture.
72
eutrophication
Microbes play a crucial role in eutrophication by rapidly multiplying when excessive nutrients are introduced into an ecosystem, leading to algal blooms and depleting oxygen levels in the water body, primarily through their decomposition of organic matter and nutrient cycling processes, particularly in relation to nitrogen and phosphorus.
