© 1998, 1999 Gregory Carey Chapter 7: The New Genetics - 1 Chapter 7: The New Genetics—Techniques for DNA Analysis Introduction Before the 1980s, finding the genotype of an individual usually involved various laboratory assays for a gene product—the protein or enzyme. The cases of the ABO and Rhesus blood groups are classic examples of how one infers genotypes from the reaction of gene products with certain chemicals. In the mid 1980s, genetic technology took a great leap forward with the ability to genotype the DNA itself. The geneticist could now examine the DNA directly without going through the laborious process of developing assays to detect individual differences in proteins and enzymes. Direct DNA analysis had the further advantage of being able to identify alleles in sections of DNA that did not code for polypeptide chains. As a result of these new advances, the number of genetic loci that could be detected increased exponentially and soon led to the identification of the genes for disorders that had remained a mystery for the better part of this century. In this chapter, the major molecular techniques are outlined. The purpose is to provide a quick and understandable reference for the social scientist. The content of this chapter is not something that is required to understand genetics, what genes are, or how they relate to human behavior. Indeed, this chapter may be skipped without any great loss of continuity. Hence, only the essentials are given and the reader interested in the laboratory science behind the techniques is referred to contemporary textbooks on molecular genetics. We begin by defining a series of basic tools and techniques. © 1998, 1999 Gregory Carey Chapter 7: The New Genetics - 2 Basic Tools and Techniques: Basic tools: Electrophoresis Electrophoresis is a technique that separates small biological molecules by their molecular weight. It may be applied to molecules as large as proteins and enzymes as well as to small snippets of DNA and RNA. One begins the procedure by constructing a “gel”—a highly viscous material the actual chemistry of which need not concern us. Purified copies of the biological specimen are then injected into a “starting lane” at one end of the gel. Finally, a weak electric current is passed through the gel for a specified amount of time. Gravity and the electric current cause the biological molecules to migrate to the opposite end of the gel. The extent to which any molecule moves depends upon its electrical charge, molecular weight, the viscosity of the gel, the strength of the current, and the amA. The simplest method to denature DNA is to h33///////////////////////(http://psych.colorado.edu/~carey/hgss/hgsschapters/HGSS_Chapter07.pdf) # cited
Answer:
C
Explanation:
25% of 16 cells is 4
If you multiply .25 by 16 you will get four and that is how many cells are dividing.
The fossil symbols and mountain belts were helpful because it showed where the land and water dinosaurs were able to live, especially with the non-swimmers in Africa and South America. There is proof of some mountains matching in Western Europe and Greenland.
A. prevent cross-contamination.
Meiosis is involved in the formation of the gametes of multicellular organisms.
<h3>How do multicellular organisms reproduce?</h3>
Both plants and animals reproduce by developing new individuals, through gametes or reproductive cells.
<h3>Characteristics of multicellular organisms reproduction</h3>
- Many multicellular organisms always arise from a single cell called a zygote, the result of the union of two gametes (female and male).
- The zygote subdivides rapidly throughout gestation, forming the entire body of the creature that, from its birth, begins to grow.
Therefore, multicellular organisms reproduce by means of certain types of reproductive cells that are generated and take care of building a complete new individual.
Learn more about multicellular organisms reproduction here: brainly.com/question/220315
