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Chapter 12 - Cloudfront.net
Chapter 12 - Cloudfront.net

... Usually disorders of chromosome number cause problems so severe the fetus dies Down syndrome  the only autosomal trisomy where the individual survives into adulthood (1 in 700 births) It is a trisomy of chromosome 21 Higher incidence in mothers over 40 years ...
Bioinformatics Factsheet
Bioinformatics Factsheet

... A dominant allele is an allele that is almost always expressed, even if only one copy is present. Dominant alleles express their phenotype even when paired with a different allele, that is, when heterozygous. In this case, the phenotype appears the same in both the heterozygous and homozygous states ...
Biology 6 Practice Genetics Problems (chapter 15)
Biology 6 Practice Genetics Problems (chapter 15)

... chromosomes in gametes and 50% parental chromosomes (as revealed by a test cross). This would be the case only if the genetic loci are at opposite ends of a chromosome, which produces the same basic outcome as with unlinked genes (50% parental genotypes, 50% recombinant genotypes). If recombination ...
Chapter 13: Patterns of Inheritance
Chapter 13: Patterns of Inheritance

... b. Eye color and sex equally represented c. Explanation: eye color gene related to sex chromosome 4. Eye Color Gene Located on Sex Chromosome in Fruit Flies a. Two kinds of sex chromosomes, b. XX = ...
Genetics Notes
Genetics Notes

... III. Punnett Squares – used to describe the ratio of expected outcomes of a genetic cross. A. Monohybrid cross – (mono meaning one) 1 trait is crossed. 1. Have two alleles for each gene. 2. Ex: T = tall, dom t = short TT x tt ...
Chapter 4
Chapter 4

... AUTOSOMAL GENETIC DISORDERS Inborn Errors of Metabolism (Continued) • Maple Syrup Urine Disease is an autosomal recessive disorder resulting in the inability to metabolize the amino acids leucine, isoleucine, and valine. Urine has a distinctive sweet smell like maple syrup. If untreated, it results ...
Genetics Notes
Genetics Notes

... 1. Principle of Dominance - when 2 forms of the same gene are present the dominant allele is expressed 2. Principle of Segregation - in meiosis two alleles separate so that each gamete receives only one form of the gene 3. Principle of Independent Assortment - each trait is ...
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How many chromosomes are shown in a normal human karyotype?

... A female with the disorder _________________________ inherits only one X chromosome and has the genotype XO. ...
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(lectures 24

... used to think that all noncoding DNA was junk, they are showing their ignorance. No one ever thought that. 43. Comparative genomics is resulting in rapid increase of knowledge about human inversion polymorphisms (a number of these have been found) and also the number of inversions in the lineages se ...
Karyotyping and Pedigrees
Karyotyping and Pedigrees

... – the long arm as the ___ arm ...
Life Science Chapter 6 Study Guide
Life Science Chapter 6 Study Guide

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MUTATIONS - Valhalla High School
MUTATIONS - Valhalla High School

... • May produce a new trait or may result in a protein that does not work correctly • In some rare cases, it may have a positive effect • Can be passed on to offspring ...
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LECTURE OUTLINE

... There are many other types of inheritance patterns other than simple dominant or recessive inheritance. Incomplete Dominance and Codominance Incomplete dominance occurs when the heterozygote is intermediate between the two homozygotes. Codominance occurs when alleles are equally expressed in a heter ...
Chromosomal Basis of Inheritance - Canisteo
Chromosomal Basis of Inheritance - Canisteo

... has a daughter with the normal phenotype. She meets a man who is also normal for the trait. What are the genotypes of everyone involved? What is the probability that the couple will have a hemophiliac daughter? A hemophiliac son? If the couple has 3 sons, what chance is there that all of them will h ...
Ch 12 Jeopardy Review
Ch 12 Jeopardy Review

... A cross between a white rooster and a black hen results in 100% blue Andalusian offspring (codominance). When two of these blue offspring are mated, the probable phenotypic ratio would be _______ ...
無投影片標題 - MADANIA
無投影片標題 - MADANIA

... features from one generation to the next is called inheritance. • The characteristics are controlled by genes which are like coded instruction. • Genes from one generation are transmitted to the next in the gametes. ...
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Genetics Lecture 9 Sex Determination reproductive modes

... • Efforts were made to accurately determine the diploid chromosome  number of humans, but because of the relatively large number of  chromosomes, this proved to be quite difficult.  • It was believed that the sex‐determining mechanism in humans was  I b li d h h d i i h i i h based on the presence o ...
Sex Linked Genetic Conditions
Sex Linked Genetic Conditions

... X linked dominant genes only require one copy of the allele for expression, whether in males or females. X linked recessive genes: ...
Chapter 6 Expanded Notes
Chapter 6 Expanded Notes

... version of an animal or plant. Something plain that contains the basic traits for that species being studied. A representative sample for that species. However, if there are members of a species with drastic variation from the norm, mainly some sort of mutation or aberration, they are referred to as ...
Asexual vs Sexual Reproduction
Asexual vs Sexual Reproduction

... do not determine the sex of an individual. • Sex chromosomes- Chromosomes that do determine the sex of an individual. ...
Historical Genetics George Mendel Mendel`s Experiment
Historical Genetics George Mendel Mendel`s Experiment

... The allele for the phenotype of blue eyes is “b” The allele for the phenotype of brown eyes is “B” A Blue eyed in individual can only be “bb” because blue eyes are recessive. An individual with Brown eyes can Have either “BB” or “Bb” because because brown eyes are dominant ...
Insight into Blindness
Insight into Blindness

... Define the term mutation and identify ways in which mutations may affect an organism   Identify the causes of mutations   Differentiate between somatic and gametic mutations and identify the potential effect of each of these.   Describe the effect of gene mutations; identify types of gene mutations  ...
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... 16. A scientist uses a pedigree to study family history. ...
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... Genetic Disorders Dominant Allele Disorders Huntington’s Disease- lose muscle control & mental function Achondroplasia- dwarfism ...
chapter 15 - Issaquah Connect
chapter 15 - Issaquah Connect

... If a female is heterozygous for a sex-linked trait, about ½ her cells will express one allele, and the other ½ will express the other allele. ...
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Skewed X-inactivation

Skewed X chromosome inactivation occurs when the inactivation of one X chromosome is favored over the other, leading to an uneven number of cells with each chromosome inactivated. It is usually defined as one allele being found on the active X chromosome in over 75% of cells, and extreme skewing is when over 90% of cells have inactivated the same X chromosome. It can be caused by primary nonrandom inactivation, either by chance due to a small cell pool or directed by genes, or caused by secondary nonrandom inactivation, which occurs by selection. Most females will have some levels of skewing. It is relatively common in adult females; around 35% of women have skewed ratio over 70:30, and 7% of women have an extreme skewed ratio of over 90:10. This is of medical significance due to the potential for the expression of disease genes present on the X chromosome that are normally not expressed due to random X inactivation. X chromosome inactivation occurs in females to provide dosage compensation between the sexes. If females kept both X chromosomes active they would have twice the number of active X genes than males, who only have one copy of the X chromosome. At approximately the time of implantation (see Implantation (human embryo), one of the two X chromosomes is randomly selected for inactivation. The cell undergoes transcriptional and epigenetic changes to ensure this inactivation is permanent. All progeny from these initial cells will maintain the inactivation of the same chromosome, resulting in a mosaic pattern of cells in females.
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