Unit 8 Flashcards
Bacteria/ Protists
What are two characteristics of prokaryotes?
No membrane-bound nucleus or organelles, has a cell wall to protect against invaders
How do prokaryotes communicate with each other?
Through quorum sensing which helps control gene expression
Approximately how many bacteria are in and on the human body?
100 trillion
What is metagenomics?
The study of the structure and function of the entire genome of prokaryotes
What are the three areas from which prokaryotic genome samples can be taken?
- Soil
- Water
- Human Body
What is a microbiome?
A collection of genomes of microbes in a particular environment
What is a microbiota?
A community of microorganisms on and in the body
Where do the majority of microorganisms live in an animal’s body?
In the gut
What is the shape of prokaryotes that form in chains?
Cocci
Give an example of a bacteria that has a cocci shape.
Streptococcus
What is the shape of bacteria that occurs singularly and is oval?
Bacilli
Give an example of a bacteria that has a bacilli shape.
E. Coli
What is the shape of bacteria that is spiral like a corkscrew?
Spirochete
Give an example of a bacteria that has a spirochete shape.
Spirilla
What color does a gram-positive prokaryote stain?
Purple
What color does a gram-negative prokaryote stain?
Pink
What protein provides a thick layer for the prokaryotic cell wall?
Peptidoglycan
True or False: Gram-positive and gram-negative stains are used to determine if bacteria are pathogenic.
True
What is the process by which most prokaryotes reproduce?
Binary fission
Fill in the blank: In binary fission, DNA ________, cell elongates, splits in half.
replicates
How does an endospore help prokaryotes survive in harsh environments?
Becomes dormant, original cell dissolves, wakes up when conditions improve
What are prokaryotes that capture energy from the sun called?
Photoautotrophs
What do chemoautotrophs do?
Harness energy stored in chemicals and make organic compounds using carbon from CO2
What are prokaryotes that get energy from sunlight and carbon from other prokaryotes called?
Photoheterotrophs
What are the largest and most diverse group of prokaryotes?
Chemoheterotrophs
What classification do ancient bacteria fall under?
Archaea
What are extreme halophiles?
Archaea bacteria that are salt lovers
Give an example of a location where extreme halophiles are found.
- Great Salt Lake
- Dead Sea
What are extreme thermophiles?
Archaea bacteria that love heat
Give an example of a location where extreme thermophiles are found.
Ocean by volcanic vents
What are methanogens?
Archaebacteria that live in the guts of ruminants and give off methane as a waste product
What defines a protist?
An organism that is NOT a fungi, plant, or animal
Where do most protists live?
In aquatic environments
True or False: The majority of protists are pathogenic.
True
What type of protists obtain their nutrition through photosynthesis?
Autotrophic
What are heterotrophic protists?
Protists that obtain their nutrition by consuming other protists and bacteria
What are mixotrophic protists?
Protists that obtain nutrition by using photosynthesis AND by consuming other protists or bacteria
What is an endosymbiont?
A prokaryote that lives within the body or cells of other organisms
Explain the relationship between termite endosymbionts and the termite.
Endosymbiont digests cellulose, termite provides place to live and nutrients
What are diatoms?
Stramenopiles that are unicellular algae and important photosynthetic organisms
What do diatoms serve as for marine animals?
A great source of energy
What type of algae are seaweed and kelp forests classified as?
Brown algae
What do water molds do?
Decompose dead plants and animals in freshwater habitats
What is Phytophthora?
A water mold that resembles a fungus and causes blight on plants
What are dinoflagellates?
Alveolates found in saltwater that are plankton and a source of energy for marine animals
What do ciliates use to sweep food into their mouth?
Cilia
What is Plasmodium known for?
Causing malaria which kills approximately 500,000 people per year
A surface-coating colony of prokaryotes that engage in metabolic cooperation is called a(n) _________.
Biofilm
Prokaryote that attaches to the host and both the prokaryote and the host get benefits from the attachment.
Mutualistic
Prokaryotes use _________ to divide in half and replicate.
Binary fission
The type of archaea that live in areas with extreme temperatures are _________.
Extreme thermophiles
Which of the following types of prokaryotes is the largest and most diverse group of prokaryotes?
Chemoheterotrophs
Which prokaryote stains purple and has a simple, non-complex cell wall?
Gram-positive
Prokaryote that attaches to the host and benefits from the attachment and the host has no effect on it.
Commensalistic
Which prokaryote stains pink and has a complex cell wall?
Gram-negative
The study of the structure and function of entire genome of prokaryotes is called _________.
Metagenomics
Which of the following is a beneficial factor to the environment provided by biofilms?
Purifying the water of dangerous bacteria
The type of archaea that live in waters with a high salt concentration are _________.
Extreme halophiles
Which of the following types of prokaryotes uses energy from the sunlight AND carbon from other organic molecules as nutrients?
Photoheterotrophs
Type of prokaryotic shape that is spiral like a corkscrew.
Spirochete
The collection of genomes of microbials in a particular environment is known as _________.
Metagenomics
It is estimated that most bacteria can produce a new generation in __________.
1-3 hours
Which of the following types of prokaryotes capture energy from the sun and use carbon dioxide to produce oxygen as a by-product?
Photoautotrophs
In harsh conditions, a prokaryote will form a(n) __________ which goes dormant until environmental conditions improve to sustain life.
endospore
This structure is a projection that is hair-like and allows the prokaryote to attach to the host or other prokaryotes.
Fimbriae
The type of archaea that live in the digestive tracts of most herbivores and helps them break down cellulose are _________.
Methanogens
Which of the following is dominant in the gastrointestinal tract of animals?
Microbiota
Type of prokaryotic shape that is E.coli.
Bacilli
Type of prokaryotic shape that forms in chains.
Cocci
When a prokaryote replicates, the chromosomal DNA will replicate and the cell __________.
divides
Which of the following types of prokaryotes live in extreme environments and do not use sunlight to create energy?
Chemoautotrophs
The community of microorganisms on and in the body is called _________.
Microbiota
Prokaryote that attaches to the host and causes disease or infection.
Pathogenic
Which of the following types of prokaryotes harnesses energy stored in certain chemicals such as ammonia and iron?
Chemoautotrophs
Which of the following is a beneficial factor to the environment provided by biofilms?
Giving plant roots the ability to absorb more nutrients
Which of the following helps prokaryotes to control gene expression?
Quorum sensing
Prokaryotes use which structures to move around?
Flagella
What is the primary function of diatoms in aquatic ecosystems?
Photosynthesis
Diatoms play a crucial role in the aquatic ecosystem by converting sunlight into energy through photosynthesis.
In which habitat are slime molds commonly found?
Terrestrial forests
Slime molds thrive in moist, decaying organic matter typically found in terrestrial forests.
Which prokaryote stains purple and has a simple, non-complex cell wall?
Gram-positive
Gram-positive bacteria retain the crystal violet stain used in the Gram staining procedure.
Most protists live in ____________ environments.
aquatic
Protists are predominantly found in aquatic environments, including freshwater and marine ecosystems.
Click all that apply: An organism is considered a protist if it is not one of the following.
- Plant
- Animal
- Fungus
Protists are defined by what they are not, as they are distinct from plants, animals, and fungi.
How do water molds obtain nutrients?
Decomposition
Water molds primarily obtain their nutrients through the decomposition of organic material.
Which of the following is an example of a photosynthetic protist?
Euglena
Euglena is a protist known for its ability to perform photosynthesis due to its chloroplasts.
The majority of protists are ________________ meaning they cause disease.
pathogenic
Many protists are pathogenic and can cause diseases in humans and other organisms.
What structure allows paramecia to move rapidly through water?
Cilia
Paramecia use cilia, hair-like structures, for locomotion in aquatic environments.
A protist is defined by which of the following?
An unicellular organism
Protists are primarily unicellular organisms that can exhibit diverse forms and functions.
Seaweed and kelp forests are classified as _______ algae.
Brown
Brown algae includes various species of seaweed and kelp, which are important marine organisms.
A prokaryote that lives within the body or cells of other organisms are called
endosymbiont
Endosymbionts are prokaryotes that inhabit the cells of other organisms, often providing benefits.
Which of the following protists are both autotrophic and heterotrophic?
Euglena
Euglena can perform photosynthesis (autotrophic) and also absorb nutrients from the environment (heterotrophic).
What is the primary role of water molds in ecosystems?
Decomposition
Water molds contribute to ecosystems by breaking down organic materials, aiding nutrient cycling.
Which protist causes malaria in humans?
Plasmodium
Plasmodium is the genus of protists responsible for malaria, transmitted by mosquito bites.
Phytophthora is a water mold that resembles a fungus and causes ______ on plants that grow on vines.
blight
Phytophthora is known for causing blight, particularly in crops and vine plants.
Which prokaryote stain pink and has a complex cell wall?
Gram-negative
Gram-negative bacteria have a more complex cell wall structure and do not retain the crystal violet stain.
What is the significance of red tide events caused by dinoflagellates?
Harmful algal blooms
Red tides are significant because they can produce toxins harmful to marine life and humans.
Which structure is characteristic of ciliates, such as Paramecium?
Cilia
Ciliates are distinguished by their use of cilia for movement and feeding.
How do amoebas move?
Pseudopodia
Amoebas extend their cytoplasm to form pseudopodia, allowing them to move and engulf food.
