{"id":227,"date":"2013-01-07T03:33:29","date_gmt":"2013-01-07T03:33:29","guid":{"rendered":"http:\/\/microbiologymatters.com\/?page_id=227"},"modified":"2013-01-07T03:33:29","modified_gmt":"2013-01-07T03:33:29","slug":"tutorial-basic-cell-biology-i-answers","status":"publish","type":"page","link":"https:\/\/microbiologymatters.com\/?page_id=227","title":{"rendered":"Tutorial: Basic Cell Biology I: Answers"},"content":{"rendered":"<p><span style=\"color: #0000ff;\">What are the differences between a bacterium and a virus?<\/span><\/p>\n<p><span style=\"color: #ff0000;\">I guess there are lots of differences that one could suggest, but for me the defining one is the fact that bacteria can replicate itself without the help of a host cell. A virus cannot replicate independently. <\/span><\/p>\n<p><span style=\"color: #ff0000;\">There are several other differences, all of which are directly or indirectly related to the above:<\/span><\/p>\n<ul>\n<li><span style=\"color: #ff0000;\">Viruses\u00a0do not carry their own enzymes for making proteins, nor do they contain ribosomes which are contained in bacteria for protein production.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Viruses do not have a cell membrane or a cell wall.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Viruses tend to be much smaller than bacteria and are often only visible with the use of an electron microscope.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Viruses are not treatable with antibiotics. Some viruses however can be treated with effective anti-viral compounds.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Viruses cannot be cultured on agar plates like most bacteria. They require living cells in the form of cell cultures.<\/span><\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n<p><span style=\"color: #0000ff;\">What are the main constituents of a bacterial cell?<\/span><\/p>\n<p><span style=\"color: #ff0000;\">Bacteria are efficient replicating machines and survival experts\u00a0thus all their consituents\u00a0serve a function to these purposes.<\/span><\/p>\n<p><span style=\"color: #ff0000;\">Best to &#8220;break down&#8221; a bacterium into what is inside the cell, what is on the surface of the cell and what is attched to the surface.<\/span><\/p>\n<p><span style=\"color: #ff0000;\">Inside a bacterium: <\/span><\/p>\n<ul>\n<li><span style=\"color: #ff0000;\">Nucleoid area containing DNA. Note this is not a nucleus<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Ribosomes: Area where proteins are synthesized.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Cytoplasm: Contains nutrients, proteins and enzymes, mostly associated with allowing the bacterium to replicate.<\/span><\/li>\n<\/ul>\n<p><span style=\"color: #ff0000;\">On the surface of a bacterium: (from inside to out)<\/span><\/p>\n<ul>\n<li><span style=\"color: #ff0000;\">Cell membrane: Mediates transport of substances in and out of teh bacterium. Conatains enzymes<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Cell wall: Thinner in Gram negative bacteria than in Gram Positive. Confers rigidity to the cell. Also acts as a permeability barrier.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Capsule (not in all bacteria) : Protects against phagocytosis. Can prevent dessication of the cell.<\/span><\/li>\n<\/ul>\n<p><span style=\"color: #ff0000;\">Attached to the surface of a bacterium<\/span><\/p>\n<ul>\n<li><span style=\"color: #ff0000;\">Sex Pili (not in all bacteria): Allows DNA transfer between bacteria by conjugation.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Flagellae (not in all bacteria): Gives motility to the bacterium, allowing it to find an area where it can survive best.<\/span><\/li>\n<li><span style=\"color: #ff0000;\">Fimbriae: also called common pili. Facilitates attachment to cells eg epithelial cells.<\/span><\/li>\n<\/ul>\n<p>\u00a0<span style=\"color: #ff00ff;\">Try and draw a schematic bacterium to see if you know the basic structure. <\/span><\/p>\n<p>&nbsp;<\/p>\n<p>Of course there are some bacteria which have more specialisd components and functions. If you are looking for a distinction in an exam you will need to know about these. Consider things like plasmids, cytoskeleton, vesicles, slimes layers. The list goes on&#8230;<\/p>\n<p>Further reading:<\/p>\n<p><a href=\"http:\/\/textbookofbacteriology.net\/structure.html\">Todar&#8217;s bacteriology: Cell structure<\/a>.<\/p>\n<p><a href=\"http:\/\/en.wikipedia.org\/wiki\/Bacterial_cell_structure\">Wikipedia: Bacterial cell structure<\/a>.<\/p>\n<p>&nbsp;<\/p>\n<p><a title=\"Tutorial: Basic Cell Biology\" href=\"http:\/\/microbiologymatters.com\/?page_id=222\"><span style=\"color: #ff0000;\">Return to questions.<\/span><\/p>\n<p><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>What are the differences between a bacterium and a virus? I guess there are lots of differences that one could suggest, but for me the defining one is the fact that bacteria can replicate itself without the help of a host cell. A virus cannot replicate independently. There are several other differences, all of which &hellip; <a href=\"https:\/\/microbiologymatters.com\/?page_id=227\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Tutorial: Basic Cell Biology I: Answers<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":222,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"jetpack_post_was_ever_published":false,"footnotes":""},"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/P37jIp-3F","jetpack-related-posts":[{"id":244,"url":"https:\/\/microbiologymatters.com\/?page_id=244","url_meta":{"origin":227,"position":0},"title":"MCQS: Bacterial Cell Structure","author":"michael","date":"January 8, 2013","format":false,"excerpt":"The following are True\/False 1) Ribosomes are found in viruses? 2) The main consituent of a Gram positive cell wall is Peptidoglycan? 3) Bacterial cells have a large surface to volume ratio? 4) The cell wall may be a potential target for antibiotics? 5) The flagella allows substances in and\u2026","rel":"","context":"With 1 comment","block_context":{"text":"With 1 comment","link":"https:\/\/microbiologymatters.com\/?page_id=244#comments"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":247,"url":"https:\/\/microbiologymatters.com\/?page_id=247","url_meta":{"origin":227,"position":1},"title":"MCQs: Bacterial Cell Structure Part I: Answers","author":"michael","date":"January 8, 2013","format":false,"excerpt":"\u00a0 Answers 1) Ribosomes are found in viruses? False 2) The main consituent of a Gram positive cell wall is Peptidoglycan? True 3) Bacterial cells have a large surface to volume ratio? True 4) The cell wall may be a potential target for antibiotics? True 5) The flagella allows substances\u2026","rel":"","context":"With 1 comment","block_context":{"text":"With 1 comment","link":"https:\/\/microbiologymatters.com\/?page_id=247#comments"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":629,"url":"https:\/\/microbiologymatters.com\/?page_id=629","url_meta":{"origin":227,"position":2},"title":"Tutorial: HIV Replication","author":"michael","date":"February 8, 2013","format":false,"excerpt":"I am not a specialist virologist, so this is slightly outwith my field. However if you are going to learn a bit about viral replication then you should go no further than HIV. It is probably the most interesting. The beauty about the HIV replication cycle is\u00a0that each major step\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"hiv replication","src":"https:\/\/i0.wp.com\/microbiologymatters.com\/wp-content\/uploads\/2013\/02\/hiv-replication-1024x950.jpg?resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/microbiologymatters.com\/wp-content\/uploads\/2013\/02\/hiv-replication-1024x950.jpg?resize=350%2C200 1x, https:\/\/i0.wp.com\/microbiologymatters.com\/wp-content\/uploads\/2013\/02\/hiv-replication-1024x950.jpg?resize=525%2C300 1.5x"},"classes":[]},{"id":170,"url":"https:\/\/microbiologymatters.com\/?page_id=170","url_meta":{"origin":227,"position":3},"title":"NEWS","author":"michael","date":"January 2, 2013","format":false,"excerpt":"\u00a0 \u00a0 \u00a0 \u00a0 The Latest news In Infection or Microbiology will be posted here.... 9th May 2018: HPV Jab. 16th April 2018: C. Diff. Guidelines Discussion. 16th March 2018: Platypus milk! 14th February 2018: Drugs from dirt. 31st January 2018: Giardia Parasite. 10th January 2018: 'Aussie'flu. 13th December 2017:\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":537,"url":"https:\/\/microbiologymatters.com\/?page_id=537","url_meta":{"origin":227,"position":4},"title":"Tutorial: DNA: The Chemistry of Life: Answers","author":"michael","date":"February 4, 2013","format":false,"excerpt":"\u00a0\u00a01) In a sentence, give a definition of DNA? DNA is a chemical\/molecule which contains the genetic code for all living things. Note that viruses sometimes contain RNA, but it is controversial as to whether viruses are \"living\". \u00a0 2) Who discovered DNA and when? First discovered by Fredrich Miescher,\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":222,"url":"https:\/\/microbiologymatters.com\/?page_id=222","url_meta":{"origin":227,"position":5},"title":"Tutorial: Basic Cell Biology","author":"michael","date":"January 7, 2013","format":false,"excerpt":"Consider the two questions below: \u00a0 What are the differences between a bacterium and a virus? What are the main constituents of a bacterial cell? \u00a0 Think about these questions for a few minutes and then goto the Answers page to see how you have got on.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"_links":{"self":[{"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/pages\/227"}],"collection":[{"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=227"}],"version-history":[{"count":5,"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/pages\/227\/revisions"}],"predecessor-version":[{"id":232,"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/pages\/227\/revisions\/232"}],"up":[{"embeddable":true,"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=\/wp\/v2\/pages\/222"}],"wp:attachment":[{"href":"https:\/\/microbiologymatters.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=227"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}