Microorganisms

Question 1

How do fungi reproduce?

Answer 1

1. Asexual spores- seeds that grow into a new organism
2. Sexual spores- act like sperm and ova to form a new organism
3. Vegetative growth- portion breaks off to form new fungus
4. Budding- new fungus grows off the side of the old one.

Question 2

Fungi

Answer 2

1. Multicellular eukaryotes
2. Heterotrophic- feed on decaying material
3. Absorptive feeders- secrete enzymes that digest their food outside their bodies

Question 3

How can bacteria genetically recombine?

Answer 3

1. Transformation- picking up new DNA from extracellular environment
2. Conjugation- bacterium replicates its DNA and donates some of it through a pilus.
3. Transduction- virus carries DNA from one bacterium to another during infection

Question 4

Pilus

Answer 4

A bridge allowing bacteria to donate its DNA.

Question 5

What is antibiotic resistance/sensitivity determined by?

Answer 5

DNA. If it changes, that means the DNA has changed.

Question 6

How do bacteria reproduce?

Answer 6

1. Produces asexually through binary fission- replicates its chromosome, then splits in half. Gets half the organelles and cytoplasm.
2. Binary fission doesn’t allow for genetic recombination

Question 7

Bacteria

Answer 7

1. Single celled prokaryotes
2. Singular, circular chromosome protects DNA from damage.
3. Have ribosomes and cell walls

Question 8

Saprobes

Answer 8

Bacteria that are decomposers, get nutrients from breakout of dead matter.

Question 9

Parasites

Answer 9

Bacteria that get nutrients from the host, which harms the host.

Question 10

Symbionts

Answer 10

Bacteria that get nutrients from the host, but don’t harm it.

Question 11

Obligate aerobes

Answer 11

Bacteria that need oxygen to survive.

Question 12

Obligate anaerobes

Answer 12

Bacteria that are poisoned by oxygen and will die if exposed to it.

Question 13

Facultative anaerobes

Answer 13

Bacteria that are fine with or without oxygen.

Question 14

Auxotroph

Answer 14

1. An organism that requires supplementary nutrition. Most bacteria aren’t auxotrophs.
2. Auxotrophic bacteria need additional substances added to their growth medium. If they don’t get that substance, they can’t grow.
3. If a bacteria can grow with a missing amino acid, they aren’t auxotrophic for that amino acid. Denoted with a plus sign
4. The ability to synthesize a substance, like an amino acid, is a genetic trait.

Question 15

Wildtype

Answer 15

Bacteria that can synthesize all building blocks they need with access to a carbon source, like glucose.

Question 16

Mutualistic Relationship

Answer 16

Relationship where both individuals benefit, such as the relationship between legumes and nitrogen fixing bacteria. Bacteria live in roots and give plants nitrogen, and plants give the bacteria nutrients. Extra nitrogen goes into the soil.

Question 17

Viruses

Answer 17

1. Viruses aren’t cells, and aren’t alive, but possess genetic information and are subject to natural selection
2. Consist of a coat made of protein (capsid) and nucleic acid (genome) which can be DNA or RNA.
3. Can’t reproduce without a host cell

Question 18

Viral life cycle

Answer 18

Attaches to the host cell, typically using a receptor, then infects it by injecting its genome into the cell. Then begins a lytic or lysogenic cycle.

Question 19

Lytic cycle

Answer 19

1. Viral genome is transcribed and translated using host RNA to make viral proteins
2. Host DNA replicates the viral genome, and new genomes are packages into capsids
3. Host is broken open (lysed) by a viral enzyme so the viruses can escape and infect new hosts

Question 20

Lysogenic cycle

Answer 20

1. Virus is integrated into a host’s genome and remains dormant
2. Viral genome is replicated whenever the host replicates, infecting daughter cells.
3. If the host experiences stress, the virus can begin the lytic cycle.

Question 21

Envelope

Answer 21

Plasma membrane that covers the virus as it buds out.

Question 22

How can a virus become more severe in animal cells?

Answer 22

Animal cells don’t have a cell wall, so the virus can go through the cell membrane to escape. This allows the infected cell to stay alive for longer and produce more virus cells.

Question 23

Viruses with RNA genomes

Answer 23

1. This viruses need an RNA polymerase to replicate, because the host cell only has DNA
2. Uses an enzyme called RNA-dependent RNA polymerase
3. The virus must carry the enzyme with it to inject into the host, or synthesize it during translation of the viral genome.

Question 24

Yeast

Answer 24

Eukaryotes that reproduce by budding.

Question 25

Retroviruses

Answer 25

1. RNA viruses that go through the lysogenic life cycle. Requires RNA dependent polymerase.
2. Reverse transcriptase- the enzyme runs reverse transcription, creating DNA from RNA.
3. Many cancer causing viruses are retroviruses

Question 26

Palindrome

Answer 26

Reads the same in both directions

Question 27

Staggered cut

Answer 27

Leave single stranded tails called sticky ends that allow it to be reattached to a piece of DNA cut by the same enzyme. The tails must overlap in a complementary fashion.

Question 28

Blunt cut

Answer 28

DNA is cut straight across both strands. Can be reattached/ligated to a piece of DNA cut with any other enzyme that produces blunt ends.

Question 29

Restriction enzymes

Answer 29

1. Enzymes that recognize a particular DNA sequence and cut the strand within it
2. Bacteria use enzymes to cut and destroy foreign DNA like viral DNA, restricting the growth of the virus.
3. The bacterium’s DNA is protected by addition of CH3 to prevent the enzyme from binding there.
4. The sequence is usually palindrome
5. Give us the ability to cut and paste DNA into custom combinations.

Question 30

Plasmids

Answer 30

1. Small circular piece of DNA found in bacteria or yeast
2. Not part of a genome and can reproduce independently. Its sequence contains restriction sites
3. Some carry genes making bacteria resistant to antibiotics.

Question 31

Vector

Answer 31

Shuttle to move DNA in between species, like a virus

Question 32

DNA ligase

Answer 32

Enzyme that seals together cut pieces of DNA.

Question 33

Restriction map

Answer 33

1. Map of the location of restriction sites within a piece of DNA
2. You can isolate a gene if you know it’s bounded on either side by a certain restriction site and use an enzyme to cut it.

Question 34

Recombinant DNA technology

Answer 34

1. Creation of new DNA molecules by cutting and splicing DNA with restriction enzymes
2. If a plasmid is mixed with the DNA, it can be inserted into the bacteria, which will rapidly reproduce, and reproduce the DNA. The DNA can then be extracted.