Chapter+2+study+guide - Chapter 2 Biological Beginnings...

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Chapter 2: Biological Beginnings This chapter presents a brief historical perspective on genetic evolution as well as basic concepts and issues related to reproduction. I. Evolutionary Perspective A. Natural selection process 1. Emphasizes that the best-adapted individuals survive and reproduce. 2. Charles ___________ proposed this perspective . 3. David Buss has stimulated interest in how evolution can explain human behavior. He proposes that skills and ___________ may have also been passed down through an evolutionary selection process. B. Evolutionary psychology 1. Emphasizes the role of ___________ in “survival of fittest.” 2. Bandura rejects the “biologizing” of psychology and suggests a __________ view in which biological changes enable organisms to affect environmental conditions. II. Genetic Foundations A. DNA and the collaborative gene 1. Chromosomes are made up of _______ , a double-helix-shaped molecule that contains genetic information. 2. ___________ are short segments of DNA. Genes carry the information needed for cells to reproduce and generate the proteins necessary for life. 3. The Humane ___________ Project made a preliminary map of the human genome (a complete set of instructions for making a human organism). The Project revealed that humans only have about 20,000 to 25,000 genes, about one-fifth of the number previously believed. B. Genes and chromosomes 1. Mitosis and meiosis a. The nucleus of each human cell contains ___ chromosomes (___ pairs). One member of each pair of chromosomes comes from each parent. b. ___________ is the process by which each chromosome in the cell’s nucleus duplicates itself. c. ___________ is the process by which cells in the reproductive organs divide into gametes, which has genetic material of the parent cell. d. Reproduction begins when a female gamete (ovum) is ___________ by a male gamete (sperm). e. A ___________ is the single cell formed when the sperm and ovum unite, and contains one member of each pair of chromosomes from the mother and one from the father. 2. Sources of variability a. Meiosis creates unique chromosomes—they are not exact copies of the mother’s and father’s chromosomes. This, along with the combining of chromosomes from both parents that occurs in reproduction, provides genetic ___________ in the population. b. The presence of two X chromosomes in the 23rd pair of chromosomes indicates female sex, while the presence of an X and a Y indicates male sex. c.
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This note was uploaded on 09/01/2010 for the course HD 1004 taught by Professor Kjkim during the Fall '08 term at Virginia Tech.

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Chapter+2+study+guide - Chapter 2 Biological Beginnings...

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