RT Book, Section
A1 Carroll, Karen C.
A1 Hobden, Jeffery A.
A1 Miller, Steve
A1 Morse, Stephen A.
A1 Mietzner, Timothy A.
A1 Detrick, Barbara
A1 Mitchell, Thomas G.
A1 McKerrow, James H.
A1 Sakanari, Judy A.
SR Print(0)
ID 1114732035
T1 The Science of Microbiology
T2 Jawetz, Melnick, & Adelberg’s Medical Microbiology, 27e
YR 2019
FD 2019
PB McGraw-Hill Education
PP New York, NY
SN 9780071824989
LK accessmedicine.mhmedical.com/content.aspx?aid=1114732035
RD 2024/04/19
AB Microbiology  is  the  study  of  microorganisms,  a  large  and  diverse  group  of  microscopic  organisms  that  exist  as  single  cells  or  cell  clusters;  it  also  includes  viruses,  which  are  microscopic  but  not  cellular.  Microorganisms  have  a  tremendous  impact  on  all  life  and  the  physical  and  chemical  makeup  of  our  planet.  They  are  responsible  for  cycling  the  chemical  elements  essential  for  life,  including  carbon,  nitrogen,  sulfur,  hydrogen,  and  oxygen;  more  photosynthesis  is  carried  out  by  microorganisms  than  by  green  plants.  Furthermore,  there  are  100  million  times  as  many  bacteria  in  the  oceans  (13  ×  1028)  as  there  are  stars  in  the  known  universe.  The  rate  of  viral  infections  in  the  oceans  is  about  1  ×  1023  infections  per  second,  and  these  infections  remove  20–40%  of  all  bacterial  cells  each  day.  It  has  been  estimated  that  5  ×  1030  microbial  cells  exist  on  earth;  excluding  cellulose,  these  cells  constitute  about  90%  of  the  biomass  of  the  entire  biosphere.  Humans  also  have  an  intimate  relationship  with  microorganisms;  more  than  90%  of  the  cells  in  our  bodies  are  microbes.  The  bacteria  present  in  the  average  human  gut  weigh  about  1  kg,  and  a  human  adult  will  excrete  his  or  her  own  weight  in  fecal  bacteria  each  year.  The  number  of  genes  contained  within  this  gut  flora  outnumber  that  contained  within  our  genome  150-fold,  and  even  in  our  own  genome,  8%  of  the  DNA  is  derived  from  remnants  of  viral  genomes.