NCWC Students Power Point Presentations: [1] [2] [3] [4]

1. A Healthy Cell: DNA & Building New DNA by Erin Bryant and Alisha Nelson

Introduction:

When thinking in terms of DNA and DNA Replication, there are many intricate and important aspects that are involved. DNA is the basic building structure of genes. Gregor Mendel, also known as the father of genetics, did laboratory research involving the common garden pea plant. His discoveries showed that ones genetic makeup is a combination of genes inherited from both parents. Other important figures in the understanding of DNA were Watson and Crick. They determined that DNA was a doubled stranded helix and used models to demonstrate their findings.

For DNA replication to be a success, many important enzymes are involved; such as helicase , polymerase, and topoisomerase . After the process of replication is completed, it is important to remember that it is semi-conservative; meaning that one strand of the DNA consists of old material, and the other strand is of new material. One of the main purposes of DNA replication is for mitotic division. Once mitotic division is complete, two genetically identical daughter cells are present.

Questions:

How is DNA related to mitotic division?

What are enzymes and why are they important in DNA Replication?

What is mitotic division and what are the 6 main steps?

Besides Watson & Crick and Mendel, are there any other major figures that assisted in the understanding of DNA or DNA structure?

2. Summary of the Immune System and its response to Antigens by Ashley Harris

Introduction:

The immune system is a group of white blood cells and substances of the blood that protect us from infection. The cells are divided into 2 groups: those that are specific for the foreign agent that they attack (lymphocytes) and those that are NOT specific for the foreign agents that they attack (phagocytes, macrophages, mast cells, basophils , eosinophils , and natural killer cells). Lymphocytes are a very important part of the immune system because they respond to antigens. By counting lymphocytes on can determine whether an individual has an immunodeficiency disease like HIV.

The other cells of the immune system attack infectious agents that are too big to be engulfed by one blood cell. To protect us from disease our immune system employs two processes to produce the large amount of antibodies that we need to combat the millions of antigens that we may encounter. The first is the generation of antibody gene diversity by DNA rearrangement. In this process the genes that code for antigens are rearranged in the heavy and light chain proteins. The number of recombination of these genes is infinite making our immune system able to combat as many antigens as possible. The second process is clonal selection in which B-lymphocytes become fully activated once it receives a signal after its antibody has bound an antigen. A second signal is received and the B-lymphocyte goes on to divide and create more activated B-lymphocytes to make the same antibody.

Questions

Which cells are attacked by the HIV virus?

What is the difference between constant regions and variable regions?

Which genes and in approximately what amount are expressed in heavy chain proteins?


Name the 4 types of T-lymphocytes and explain what each does.

Define what the immune system is.

3. Primary and Secondary Immune Responses by Ahmad B. Crudup
   


4. Diagnosis of HIV and AIDS by Jessica Kremidas
   

Introduction:

This presentation will illustrate how the Aids virus, HIV, enters the body and spreads its genetic make-up throughout the host's cells. The four stages of infection will be discussed, and symptoms expressed in each stage will be exemplified. Since blood plays an important role in diagnosing HIV and Aids blood testing will be explained in more detail; the two main ways of testing blood infections are through both the ELISA test and western blotting. The progression of HIV to Aids will be portrayed, and the secondary infections that Aids victims encounter will be explained.