Ch 10: Microorganisms Flashcards
Most fungi are multicellular ______.
Eukaryotes
What are fungal cell walls made of?
Chitin
Can fungi photosynthesize?
No because they lack chloroplasts
Fungi are absorptive feeders, which means:
they secrete hydrolytic enzymes that digest their food outside their bodies
What are the methods fungi reproduce?
Asexual spores
Sexual spores
Vegetative growth
Budding
What are asexual spores?
Spores that can drop off the fungus and grow a new organism
What are sexual spores?
Spores that combine to form a new organism
What is vegetative growth?
A portion of the fungus breaks off and forms a new fungus
What is budding?
A new fungus grows off the side of the old fungus (yeast)
How can bacteria achieve genetic recombination?
Transformation
Conjugation
Transduction
What is transformation?
Bacteria pick up new DNA
What is conjugation?
A bacterium replicates its DNA and donates some of it to another bacterium through a bridge called a pilus
What is transduction?
A virus carries DNA from one bacterium to another during infection
What are obligate aerobes, obligate anaerobes, and facultative anaerobes?
Bacteria that need oxygen
Bacteria that need no oxygen
Bacteria that can use oxygen but don’t have to
What is an auxotroph?
An organism that requires supplementary nutrition
If a substance that cannot be synthesized is added to the growth medium can the auxotroph grow?
No =(
If bacteria are auxotrophic for an amino acid, what is it denoted with?
a minus sign
If a bacterium can grow in the absence of a particular amino acid, is it auxotrophic for that amino acid?
No
Some nitrogen-fixing bacteria form a symbiotic relationship with the roots of what plants?
Legumes
A virus has a coat made of protein called a _____ with nucleic acid/ the genome inside of it
capsid
Viruses can reproduce only with ________
the help of another cell
How does the viral life cycle begin?
Attachment- virus attaches itself to the host cell
Infection- virus injects its genome into the host cell
What happens in the lytic cycle?
The viral genome is transcribed and translated to make viral proteins, they are replicated and made into new capsids. The host is then lysed (broken open) and new viruses escape
What happens in the lysogenic cycle?
The viral genome is integrated into the host’s genome and remains dormant until the host cell experiences stress and it begins the lytic cycle.
Animal cells do not have a cell wall, so viruses that infect them do not ______
have to lyse them to escape
A virus with an RNA genome needs what to replicate?
an RNA-dependent RNA polymerase
Fungi are classified as ______
Eukaryotes
Do bacteria have mitochondria, ribosomes, and cell walls?
No, yes, yes
Yeast are _______ that reproduce by _______
Eukaryotes, budding
A viral _____ is made of protein
capsid
_______ occurs when a virus transfers some DNA from one bacterium to another
Transduction
Can fungi photosynthesize?
No
Bacteria that can chill in the presence or absence of oxygen are called ________
faculative anaerobes
Are all fungi eukaryotes?
Yes
When a bacterium replicates its DNA and gives some of the DNA to another bacterium through a pilus, this is called
Conjugation
Fungi have a cell wall made of _____
chitin
Bacteria are classified as ________ and therefore ____ have nuclei
Prokaryotes, do not
An enzyme that makes a strand of RNA by reading a strand of DNA is called
RNA-dependent DNA-polymerase
Retroviruses go through the _____ life cycle
lysogenic
A ________ cut of DNA by a restriction enzyme produces sticky ends
staggered
A piece of DNA cut with a restriction enzyme that produces sticky ends can be litigated to any piece of DNA cut with what?
The same restriction enzyme
The enzyme that seals together cut pieces of DNA is called ______.
DNA ligase
A sequence of DNA that reads the same from both directions is called a ________.
Palindrome
Can a piece of DNA cut with a restriction enzyme that produces blunt ends be litigated into a plasmid cut with any other restriction enzyme?
No
What is a restriction enzyme?
An enzyme that recognizes a particular short DNA sequence and then cuts the DNA strand within that sequence
What do bacteria use restriction enzymes for?
To cut foreign DNA
If a piece of DNA is cut with a restriction enzyme that produces sticky ends, what can it be reattached to?
Any other piece of DNA cut with the same restriction enzyme because they have to overlap in a complementary fashion.
In a blunt cut, how is the DNA cut?
straight across both ends
What is a plasmid?
A small circular piece of DNA frequently found in bacteria. It contains restriction sites.
How is recombinant DNA technology used?
To study DNA sequences of species that do not reproduce rapidly
What do restriction enzymes give us the ability to do?
Recombine DNA into custom combinations
What do vectors do and what are some examples of them?
Shuttles used to move DNA between species
plasmid, virus
