LAB EXERCISE D; THE CELL by Professor Fink

In this Video Lab, Professor Fink describes the structure of a Cell and explains how to examine cells under the microscope. Reference is made to the Cell Theory, prokaryotic cells, eukaryotic cells, plant cell, animal cells, Elodea, onion & cheek cells.
Check-out professor fink's web-site or additional resources in Biology, Anatomy, Physiology & Pharmacology: www.professorfink.com
Down-loadable e-Books of the Lecture Outlines by Professor Fink can be purchased from the WLAC Bookstore at: wlac.redshelf....
“Hard Copy” Lecture Outlines can be purchased from the WLAC Bookstore at: onlinestore.wla...

[@kristinalearns]

Thank you so much, professor. Your lectures are absolutely wonderful!

[@bless1012]

Thank you, Professor Fink.

[@nick1f]

If viruses are not living organisms, how do they replicate and constantly change?

[@professorfink]

The viral particle enters a "host cell" and the host cell makes copies ("replicates") of the virus. Since the virus consists of a Nucleic Acid (DNA or RNA), the Nucleic Acid undergoes spontaneous mutations just like the DNA in any living cell.

[@nick1f]

Thank you for explanation. Are we also affected by spontaneous mutations in our DNA? What happens with the cells in our bodies that end up with different DNA? Are they destroyed by lymphocytes or do they survive and multiply?

[@professorfink]

There are spontaneous mutations that occur in the DNA of our cells. In addition, exposure to "mutagenic agents" (such as certain chemicals, like benzopyrene; radiation & "lysogenic viruses", like the Human Papilloma Virus) increase the rate of genetic mutations. Mutated cells are destroyed by the Immune System (lymphocytes). Those mutated cells that are not destroyed may become cancerous. This is the basic cause of cancers in the body: repeated mutations (& why benzopyrene in cigarettes, UV radiation & lysogenic viruses can cause cancer).