Module 7. Chapter 12 The Eyukaryotes. Fungi : the study of fungi Fungi important in food chain o dead matter o Recycle Used for, produce food,

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1 Mdule 7 Chapter 12 The Eyukarytes Fungi : the study f fungi Fungi imprtant in fd chain dead matter Recycle Used fr, prduce fd, Mst are r anaerbes Few anaerbes knwn Characteristics f fungi Multicellular fungi identified based n Clny characteristics, reprductive spres Classified int 3 grups: Mlds and fleshy fungi : bdy f fungus Cnsist f f cells jined tgether called r (singular) : filamentus mass f fungi Hyphae grw by elngating at the Each is capable f Fragments that can frm new hypha hypha: prtin f thallus that btains à actively prtin Hypha Mst hyphae have int cell- like units Hypha Few have Appear as lng cntinuus cells with Reprductive Hyphae Cncerned with Aka hyphae Prject the surface

2 Yeasts, unicellular fungi Typically r Yeasts divide Daughter cell ( ) is than parent cell Yeasts capable f grwth Can use as final electrn acceptr Prduce and water Can use as final electrn acceptr Frms and Imprtant in fd industry Dimrphic fungi Can grw as r In pathgens, is temp- dependent C yeastlike C mldlike Characteristics f Fungi Fungi are Cmpete with fr fd Nutritinal characteristics prvide sme advantages Fungi can grw Resistant t Can grw in lw, lw envirnment Capable f degrading ; lignin in wd Life Cycle f Fungi Reprductin accmplished by frming Spres frm parent int new mld fungi Prduce bth and spres fungi Prduce nly spres Spres can survive fr extended perids in, t the extreme like bacterial Filamentus fungi reprduce by fragmenting Asexual spres frmed by hyphae Spres are Cnidispres Spre enclsed in Cnidia (pl) r prduced in chain at end f Arthrspres

3 A type f Septate hyphae fragment int a, spre, an Sprangispres Frmed within r at end f Can cntain hundreds f Sexual Reprductin Sexual spres result frm f Requires ppsite Spres have characteristics f : fusin f haplid cells prduces ne : frmed in a sac ( ) : frmed externally n a ( ) Fungal Diseases : a fungal infectin Generally (lng- lasting) because fungi Classified int 5 grups accrding t Degree f tissue invlvement Mde f entry int hst mycses Infectins the bdy Rute f entry is Begin in, spread t ther tissues mycses Fungal infectins Infectin ccurs by f spres Sprtrichsis is subcutaneus infectin acquired by gardeners, farmers mycses, mycses Infect epidermis, hair, and nails Secrete, keratin in hair, skin Transmitted by mycses Lcalized alng, skin cells is invaded, ften unaware f infectin pathgen Generally in nrmal habitat Becmes pathgenic in hst Under treatments with antibitics, suppressed immune system Chemtherapy Difficult t target fungi cells are Structures, metablism is Sterls in differ in fungi

4 Ergsterl vs chlesterl Fungal are als a target In general, anti- fungal treatments require Fungi grw than bacteria Ergsterl Synthesis Inhibitrs Causes excessive f membranes Plyenes: Amphtericin B mst cmmn, but t kidneys Azles Mst widely used anti- fungal Imidazles used as fr athlete s ft and yeast infectins Triazles (flucnazle, itracnazle) have, very cmmnly used Cell Wall Synthesis Inhibitrs Primary target is, fund in chitin cell wall Incmplete cell walls lead t Echincandins useful fr myses LIchens Mutualistic cmbinatin f an (r a cyanbacterium) and Alga prduces and secretes ; fungus prvides Clnize habitats that are fr either the alga r the fungus alne grwing Three mrphlgic categries lichen: grw r encrusting n surface lichen : lichen prjectins Prtza Characteristics f prtza Unicellular Inhabit water and sil : feeding and grwing stage Relatively few cause disease But diseases are significant Invlve cmplex Often with multiple Reprduce asexually and : frmatin f a called a Occurs as part f Parasites can survive Mstly Sme capable f anaerbic grwth All live in areas with

5 Malaria : causative agent f malaria Anpheles msquit is hst - Human is hst reprductin Txplasmsis - causative agent f txplasmsis Felines are Mammals are Cysts are excreted in feces f cats Humans r cysts Especially harmful t à can cause Helminths Characteristics f helminthes eukarytic animals Parasitic helminths have characteristics that differ frm free- living helminths Lack system Reduced system Reduced r absent Cmplex system (hermaphrditic) Male and female reprductive systems in Separate male and female à à Tw grups f helminths and Platyhelminths The à flukes and tapewrms Nematdes The Tw mdes f transmissin Eating f, Excreted in Eating f Frm Lung Fluke: are definitive hsts Lives in, excreted in are intermediate hsts Humans infected by frm mllusks

6 Trichinsis: Nematde grws inside intestines Humans gets infected by eating Rat Lungwrm: are definitive hsts Lives in, excreted in are intermediate hsts Humans get infected by eating Humans are r hsts Can be, but nt Chapter 13 Viruses, Virids, and Prins General characteristics f viruses Especially Can t be frm slutin Obligate parasites N when islated Multiply living cells Cause synthesis f special structures Cntain type f nucleic acid ( r ) Prtein cat ( ) surrunding the nucleic acid Sme are enclsed by an Viruses have enzymes f their wn Cmpletely n hst cell Antiviral treatments Drugs that target replicatin machinery als target hst cell range: the f hst cells that virus can Mst viruses are limited t cell type f hst species Hst range determined by: Virus requirements fr Availability f fr multiplying Viral hst range gives ptential in Use f bacteriphage t treat infectins viruses infect nly tumr cells Virins, fully infectius viral particle Cmpsed f, surrunded by a Capsid prtects virus, determines Nucleic acid can be either r genme, never Can be stranded (ds) r stranded (ss)

7 Viruses classified by Sme viruses have capsid cvered by an made f,, carbhydrates Helical Viruses Resemble Can be r Plyhedral viruses Many Mst are : 20 triangular faces, 12 crners Envelped viruses Cvered by Frm plasma membrane frm Can be envelped, envelped used fr Cmplex viruses structures in additin t capsid Additinal structures can include, tail pin,, baseplate Taxnmy f viruses Classificatin f viruses is based n type f, replicatin, Family names end in Genus names end in Viral species: grup f viruses that share same and names are used fr species Subspecies are designated by a Grwing Viruses Viruses cannt replicate f hst In labratry, viruses must be cultures in Grwing animal viruses in the labratry 1. In Include mice, rabbits, and guinea pigs Mst studies f invlve live animals Sme viruses cannt be grwn in animals, r d nt cause disease, HIV has n live animal mdel Difficult t study 2. In embrynated Cnvenient and is drilled in f embrynated egg Viral suspensin, virus cntaining tissue injected Many membranes in egg can supprt grwth f virus Many viral prepared in eggs

8 3. In Preferred grwth medium f viruses ppulatin f cells, handle much like, t wrk with than live animals, eggs Cell cultures (nt ) grwn in liquid culture media in lab Viruses grw in Viral multiplicatin Multiplicatin f animal viruses All animal viruses have similar life cycles Majr difference between viruses is in, Attachment Attach t ( ) n hst distributed all ver viruses r Entry Nnenvelped viruses enter by Transprt f mlecules int a cell via vesicles Envelped viruses enter thrugh f t hst membrane Uncating Separatin f frm Many ways this happens Bisynthesis and Maturatin Bisynthesis f viral DNA à viral f viral mrna à viral Uses mstly enzymes Maturatin f Release Nnenvelped viruses released by plasma membrane Envelped viruses btain envelpe by Assembled pushed thugh Live Cycle f Envelped Virus à HIV genme Must cnvert int

9 Uses enzyme HIV infects cells ( cells) A white bld cell binds t prtein n T cell Prtein receptr Helper T cells HIV enters cell fuses with membrane Uncating cnverts viral RNA int DNA Retrviral DNA enters Inserts int Integrated viral DNA is knwn as Can exist in r state Prductive state HIV matures Maturatin Released by Viruses and cancer : genes assciated with cancer Many ncgenes cntrl when a cell Activated ncgenes transfrm nrmal cells int cells cells grw uncntrlled, leading t The genetic material f viruses becmes integrated int the hst cell s à frms Insertin can activate Latent viral infectins Viruses remains hst cell fr lng perids Persistent viral infectins Disease prcess ccurs ver a lng ; generally