Unit 5 Flashcards
Obligate intracellular parasite
An organism or parasite that requires a host cell in order to reproduce
Virulent
Viruses that cause disease
Lytic cycle
Virulent viruses
Ex measles and common cold
Steps of lytic cycle
Attachment, nucleic acid entry (viral dna enters host cell and breaks down host dna), replication, assembly, release
Lysogenic cycle steps
Attachment, Nucleic acid entry, integration (virus is incorporated into host dna), replication, viral dna is copied w dna so infected
Lysogenic viruses
Shingles, warts, hiv, herpes
Can result in new properties for the host
Retroviruses
Arnie viruses that replaced by transcribing it’s our need to DNA and then putting their DNA in the cellular DNA
Ex hiv
Reverse transcriptase
Enzyme found in some virus that uses rna as a template to make DNA
Retroviral integrase
Catalyzes the cut and paste action of clipping the host dna and then inserting the viral DNA
Vaccination
Solution that contains a Homo strain of the virus which stimulates the immune system
Antiviral drugs
Chuck’s to interfere with viral nucleic acid synthesis
Pilus
Short hair like structures that help join two bacterial cells
Often transfer dna from one bacterium to another
Endospores
The dormant structure that protects bacteria against harsh conditions
Endospores made of
Thick outer covering that surrounds the DNA
chemotaxis
Directed movement toward or away from a chemical stimulus
In harsh conditions
Fruiting bodies are formed in which bact do diff tasks leading to cooperation and more efficiency to survive harshness
Binary fission steps
- Copies dna
- Chrom move to opp sides of cell
- Cell grows
- Cell pinches into two identical cells
Bacteria reproduce asexually by binary fission ir sexually by conjugation
.
Transformation
When A bacterial cell takes in DNA from its outside environment
Conjugation
When one bacteria transfers its DNA to another bacteria cell
Transduction
When a virus transfers bacterial DNA from one bacteria to another
Transposition
The movement of DNA segments within and between DNA molecules
Bacteria modes of nutrition
Photsynthesis Chemosynthesis (Capture free energy from small in organic molecules) autotrophs no oxygen, heterotrophs
Obligate aerobes
Organisms that must have oxygen for cellular respiration and cannot grow without it
Obligate anaerobes
Organisms that die in the presence of oxygen live only on fermentation
Facultative anaerobes
Use oxygen if it is available, but when oxygen not available undergo fermentation
Metabolic cooperation
Cooperation between prokaryotic cells allows them to use environmental resources they cannot use as individuals
Thermophiles
Live hot environments
Halophiles
Live salty environments
Methanogens
Use carbon dioxide to oxidize hydrogen and produce methane as a waste product
Protists include
All eukaryotes that are not plants animals and fungi, most unicellular
Protists nutrition
Photsynthesis or heteroptrophs or mixotrophs (can both photosyn and heterotroph)
For energy in protists
Most use aerobic respiration and have mitochondria
Reproduction in protists
Asexual, sexual in meiosis or fertilization, fruiting body mechanism in harsh conditions by releasing spores
Most protists are
Aquatic and havd origins in endosymbiosis
Most fungi are
Multicellular filaments
Fungi food
Heterotrophs, obtain nutrients through absorption- secrete exoenzymes which break down food
Some fungi live as decomposers others as parasites
Some live as mutualists
Symbiotic relationships w fungi
Mycorrhizae: when a fungus lives symbiotically it with plants usually attached to the root
Fungi absorbs ground nutrients and get em from stuff made by plant
Lichens: when a fungus lives symbiotically with a photosynthetic micro organism such as green algae or cyanobacteria
Fungus absorbs water and minerals from air and other provides food and energy thru photosyn
Fungi are found
For most everywhere
Fungi structure
Cell wall=chitin
Made of tiny threadlike filaments called hyphae
Many hyphae form mycelium, which infiltrates the material on which fungus feeds
Mycelium structure maximizes its
Surface area to volume ratio making feeding efficient
Asexual fungi reproduction
Make haploid spores released from fruiting bodies
Fragmentation: mycel breaks off
Budding: small cell forms and pinches off as full sized
Sexual fungi reproduction
Hyphae from 2 diff mycel release phermones amd move towards other, haploid hyphae fuse, if nuclei not fused imed then called heterokaryon, nuclei fuse forming diploid zygote, new zygote does meiosis and makes haploid spores= new fungi
