For this topic, you should be able to identify the organelles based on their characteristic features. Since students tend to be confused over the following organelles, visit the URLs at least once and remember.
Look out for the following in the organelles:
Nucleus - black spot(s) (nucleolus/nucleoli), (nuclear) pores may be visible at times
rER - lots of black dots (ribosomes) on the surface of the organelle
sER- numerous tubular sacs
GA - a stack of flattened sacs with vesicles
Mitochondrion - infolding of membrane (cristae) w/n organelle
Chloroplast - stacks of membranes (grana) w/n organelle
Ribosomes - small dots suspended in the cytosol or attached to the ER (as rER)
(P.S. The above descriptions are for you to recognize and identify the organelles, and may not be suitable as exam answers. Refer to your notes for the correct descriptions of the characteristic structural features.)
Nucleus (including nucleolus and nuclear pore)
1) http://en.wikipedia.org/wiki/File:Micrograph_of_a_cell_nucleus.png (nice electron micrograph showing at least one distinct nucleolus, you can also see a nuclear pore on the right; it is not a cell as the rER are clearly present)
2)https://www.biomedia.cellbiology.ubc.ca/cellbiol/user/scripts/qry_media_id.php?media_id=152 (electron micrograph of labelled nucleus and other organelles)
3) http://www.etap.org/demo/grade7_science/Image32.gif (a labelled diagram showing how the outer membrane of the nucleus continues to becomes the membrane of ER)
4)http://kentsimmons.uwinnipeg.ca/cm1504/nucleus.htm (nice drawing; scroll down to view other organelles)
Mitochondrion
1)http://microbewiki.kenyon.edu/index.php/File:Mito_pic_diagram.gif (nice electron micrograph and drawing)
(nice picture of drawing and electron micrograph)
2)http://www.bmb.leeds.ac.uk/illingworth/dance/mito.gif (nice labelled electron micrograph)
3)http://kvhs.nbed.nb.ca/gallant/biology/mitochondrion.jpg (note that circular DNA and 70S ribosomes are found in the matrix!)
Chloroplast
1)http://www.agri.huji.ac.il/~zacha/images/chloroplast.jpg (v clear and labelled electron micrograph)
(close up of characteristic feature - grana linked by intergranal lamellae)
3)http://www.biology.iupui.edu/biocourses/N100/images/ch9chloroplast.jpg (remember that chloroplasts are organelles in plant cells!)
(a simple drawing but that site has a nice overview of the light and dark rx and animation)
(chloroplasts in a plant specimen slide seen under a light microscope)
Rough and smooth endoplasmic reticulum
(a nice picture showing the characteristic numerous sac-like structures of sER; scroll down to view rER - note the difference!)
(beautiful electron micrograph showing sER, rER and mitochondrion; by now you should be able to recognize the diff organelles!)
3)http://www.visualphotos.com/image/1x8466949/smooth_endoplasmic_reticulum_tem (a nice electron micrograph of sER beside a mitochondrion)
(scroll down - close up of rER and sER next to each other)
Golgi body (or apparatus)
(electron micrograph of the characteristic GA; view the site once for other organelles)
2) http://www.cytochemistry.net/cell-biology/golgi.htm (drawing showing cis face of GA receiving vesicles pinched off from ER)
2) http://www.cytochemistry.net/cell-biology/golgi.htm (drawing showing cis face of GA receiving vesicles pinched off from ER)
3)http://kentsimmons.uwinnipeg.ca/cm1504/nucleus.htm (scroll down to see Golgi apparatus)
4) http://creationrevolution.com/2010/11/golgi-apparatus-steel-industry-of-the-simple-cell-%E2%80%93-part-6/ (shows the transport of a secretory protein from the rER to the Golgi body and secretion out of cell via exocytosis - good for revising the membrane system)
(nice drawing showing the fusion of vesicles to cis face and the forming of vesicles from the trans face of GA)
Lysosome
(nice electron micrograph of a lysosome breaking down a mitochondrion)
2) http://apbio-werle.wikispaces.com/Cell+and+Cell+Transport+%28Ch+6-7%29 (scroll down to see the lysosome in action - digesting phagocytic vesicle and worn out organelle)
3) http://faculty.une.edu/com/abell/histo/Histolab4a.htm (scroll down to see lysosome; remember lysosome is made from GA)
3) http://faculty.une.edu/com/abell/histo/Histolab4a.htm (scroll down to see lysosome; remember lysosome is made from GA)
Ribosome
1)http://bass.bio.uci.edu/~hudel/bs99a/lecture22/index.html (polyribosome / polysome; good to read the info once)
2) http://www.uni-mainz.de/FB/Medizin/Anatomie/workshop/EM/EMRibosomE.html (confusing? just know that ribosomes are so small they appear as dots on electron micrographs)
3)http://kentsimmons.uwinnipeg.ca/cm1504/nucleus.htm (scroll down to view free and bound ribosomes)
4) http://sandwalk.blogspot.com/2007/10/compositon-of-ribosomes.html?showComment=1192732380000
4) http://sandwalk.blogspot.com/2007/10/compositon-of-ribosomes.html?showComment=1192732380000
(shows composition of 70S and 80S ribosome; fyi only)
5)http://bass.bio.uci.edu/~hudel/bs99a/lecture21/index.html (polyribosome electron micrograph + diagram)
(computer model showing the 3 binding sties of ribosome; good to use it when revising translation!)
Centriole
1) http://mvc.bioweb.dcccd.edu/weblinks/cilia.htm (scroll down to view electron micrograph)
2)http://sciencyscience.tumblr.com/post/130146054/biology-textbook-treasures (note the "centrosome" where centrioles are found; some cells do not have centrioles but spindles can still be formed)
3)http://www.nature.com/nrm/journal/v8/n6/fig_tab/nrm2180_F2.html (shows the duplication of centrioles during interphase)
Others
(nice photo of myelinated neurone and node of Ranvier)
2) http://apbrwww5.apsu.edu/thompsonj/Anatomy%20&%20Physiology/2010/2010%20Exam%20Reviews/Exam%201%20Review/Ch03%20Cell%20Organelles%20&%20Cytoskeleton.htm (great picture of a typical eukaryotic cell with description of various organelles but some organelles are not in the A level syllabus; refer to the syllabus).
Select some of the pictures and use them during your revision. This will help you remember the features of the organelles and processes in other topics! Remember - study smart!
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