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sec 11.3
Chromosomes and Human Heredity
| Question | Answer |
|---|---|
| A photograph of pairs of homologous chromosomes arranged in decreasing size. In a human this consists of 23 pairs, 22 pairs of autosomes and 1 pair of sex chromosomes | Karyotype |
| this tool of genetics can help determine chromosome errors such as missing chromosomes or extra chromosomes | Karyotype |
| During meiosis the sister chromatids may not separate properly, causing the wrong number of chromosomes in gametes and organisms...this is called ? | Nondisjunction |
| Two chromosome conditions that can result from nondisjuction | monosomy and trisomy |
| Having a set of three chromosomes of one kind is called | trisomy |
| having only one of a particular type of chromosome is called | monosomy |
| A condition that is the result of 3 #21 chromosomes ( a trisomy of #21) | Down Syndrome |
| What factor causes the frequency of Down syndrome to increase | older mothers |
| What problems come about as a result of Down Syndrome | distinctive facial features, short, heart defects, and mental disabilities. |
| Types of chromosomes that can do go through nondisjuction | autosomes and sex chromosomes |
| The normal sex chromosomes of a female are XX but with nondisjunction the sex chromosomes could be ______ ( a monosomy) or ______ ( a trisomy) | XO or XXX |
| the normal male sex chromosomes are XY... two trisomy conditions that result from nondisjunction of male sex chromosomes are ____ or _____ | XXY or XYY... ( the monosomy OY results in death) |