Biology Flashcards
(140 cards)
Describe the types of bacteria shapes?
Cocci, Bacilli, Spirill
Cocci:
spherical shaped bacteria
Bacilli:
rod shaped bacteria
Spirilli:
spiral shaped bacteria
Describe the difference between an anaerobe and aerobes?
The main difference between anaerobe and aerobe is that aerobes require oxygen to metabolize thus the name aerobe where as anaerobes do not require oxygen to metabolize thus the name anaerobe.
Gram positive:
the cell has a thick layer of peptidoglycan which is made from sugars and AA, it will also contain lipoteichoic acid which can create an immune system response.
Gram negative:
the cell wall contain peptidoglycan but only in small amounts and contain lipidsccarides which have a more triggering immune system response.
what is the unique function of a plasmid?
in prokaryotic cells a plasmid carries DNA that is not important for fundamental life and development and they are not considered as part of the genome however plasmids might be the key to antibiotic resistance.
What is Binary fission?
form of asexual reproduction of prokaryotes that results from DNA replication and split into two daughter cells from the prokaryote.
Describe the concept of genetic recombination and the methods by which bacteria can diversify themselves?
Genetic recombination is the process in which bacteria integrate DNA from episomes into their DNA and become more diversified bacteria and helps the evolution of the species over time these happen through three mechanisms
- transfromation
- Conjugation
- Transduction
Transformation:
integration of forgegin genetic material into the host genome and the foreign genetic material most frequently comes from bacteria
Conjugation:
bacterial form of mating (sexual reproduction) two cells from a conjugation bridge that facilitates the transfer of genetic material from a donor male to a recipient female and this is a UNIDIRECTIOAL transfer
> bacteria must contain sex factors that are plasmids that contain the necessary genes, this allows for genetic recombination and gaining anit-biotic resistant factors
Transduction:
ONLY genetic recombination process that requires a vector which is virus that carries genetic information from one bacterium to the other
What are transposons?
genetic elements that are capable of inserting and removing themselves from the genome
What happens if a patient is given an antibiotic and does not fully fish the treatment?
if a patient fails to complete the antibiotic treatment often discontinuing the treatment because they feel fine the creates antibiotic resistance and kills off the bacteria that are non resistant and leaving bacteria that is more resistance to reproduce resulting in a recurring infection
What is a virus?
genetic material that is composed of a protein coat and sometimes an envelope containing lips this genetic info can be DNA, RNA single or Double stranded
What is the protective case around a virus called?
capsid is the protein coat around a virus, these coats are very sensitive to heat, detergent etc.
Can virus reproduce independently or live on their own?
NO, they must express and replicate genetic information within a host cell because they lack the ribosome to carry out protein synthesis
What is a bacteriophage, is it bacteria or a virus?
bacteriophage is a virus that specifically targets bacteria, however they do not enter the bacteria they simply inject genetic material
What is the difference between positive sense and negative sense in viral genomes?
Positive Sense: genome my be directly translated to functional proteins by the ribosomes of the host cell just like mRNA, RNA virus stay in cytoplasm and are directly translated into proteins by host cell ribosome
Negative Sense: RNA virus that the RNA acts a template for synthesis of a complementary strand which can be used as a template fro protein synth and contain RNA replicase which ensure that the complementary strand is synthesized. Require the synthesis of a complementary RNA strand through RNA replicase that is translated and formed into protein
What are Retroviruses?
single stranded RNA virus that contain two identical RNA molecules that carry an enzyme called reverse transcriptase which synthesizes DNA from a single strand of RNA this DNA integrates into the host genome and replicated as its own host genome (like in HIV)
How can the concept of retroviruses be important in gene therapy?
retoerovisus and transduction are potentially going to be used in gene therapy, it can give functional version of a gene so that correct proteins can be synth for certain disease
Lytic:
Bacteriophage maximizes the use of the cells own machinery to replicate which no regard to the host cell, lysing the host genome
Lysogenic cycle:
virus becomes part of the host genome and my integrate into the host genome indef. however environmental factors can cause viruses to revert to the lytic pathway.