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Biology~Chapter 12
Biology~Chapter 12

... • are traits that are coded for by alleles on a sex chromosome. • Genes found on the X chromosome are X-linked genes • Since the X chromosome is larger- there are more X-linked than Y- linked traits. NOTE: Since males have only 1 X- a male who carries the recessive allele will show the X-linked trai ...
Notes and Study Guide for weeks 8
Notes and Study Guide for weeks 8

... D. What is meant by an organism’s fitness? What is meant by relative fitness? Why is this really the most important aspect of one’s reproductive success in terms of natural selection? E. What are 3 things that influence variation in a trait (the mix of alleles in a population for that trait)? How do ...
Chapter 14
Chapter 14

... Colorblindness is much more common in males than in females because A. the recessive gene on the male’s single X chromosome is expressed. B. genes on the Y chromosome make genes on the X chromosome more active. C. females cannot be colorblind. D. colorblindness is dominant in males and recessive in ...
Biol 211 (2) Chapter 13 KEY
Biol 211 (2) Chapter 13 KEY

... original tumor and invade other tissues ...
Russian Academy of Sciences, Kurchatov Sq.46,
Russian Academy of Sciences, Kurchatov Sq.46,

... Figure l. Arrangement of genetic loci in the Pgd-KIO region of the Drosophila X chromosome. The orientation is from centromere-distal (left) to centromere-proximal (right). Added or changed loci are marked by asterisks (see text). Tolchkov 1985, Dros. Inf. Servo 61 :24; Alatortsev, V.E., LA. Kramero ...
Genetics Exam 5
Genetics Exam 5

... _____ When an allotetraploid is backcrossed to one of its progenitor species, a sterile progeny is produced. The genomic composition of this sterile individual can be best represented by A. n1 + n2 B. 2n1 + 2n2 C. 2n1 D. 2n2 E. 2n1 + n2 _____ Euploidy is A. a chromosome number that is not an exact ...
Ch 15: Chromosomal Basis of Inheritance
Ch 15: Chromosomal Basis of Inheritance

... • Females must be homozygous recessive to display trait (XX – second X can mask recessive) • Females can be carriers • Males only need to inherit a single copy to show trait • Can a male be a carrier? ...
Chromosomes and Genetics
Chromosomes and Genetics

... - paired chromosomes segregate (separate) during meiosis. Each sex cell has half the number of chromosomes which is why gametes have only one of each of the paired alleles Each chromosome contains many different alleles and each gene has a specific locus on a particular chromosome ...
The Chromosomal Basis of Inheritance
The Chromosomal Basis of Inheritance

... testes/male characteristics ...
MUTATIONS
MUTATIONS

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Stem Cells, Cancer, and Human Health
Stem Cells, Cancer, and Human Health

... Somatic mutations: not passed on to kids Mutations in gametes: can be passed on Sources of genetic disorders: 1. Mutations in individual genes 2. Abnormal chromosome number 3. Gene turned on/off (epigenetics) not in book!!! ...
Sex-Linked Traits Worksheet
Sex-Linked Traits Worksheet

... Sex-linked traits are those whose genes are found on the X chromosome but not on the Y chromosome. In humans the X chromosomes are much larger than the Y chromosome and contains thousands of more genes than the Y chromosome. For each of the genes that are exclusively on the X chromosomes, females, w ...
Chapter 11 Complex Inheritance and Human Heredity
Chapter 11 Complex Inheritance and Human Heredity

... Recessive Genetic Disorders Mendel’s work went unnoticed by the scientific community for about 30 years then it was rediscovered in the early 1900s.  At that time many scientists were interested in the cause of diseases and noticed that some diseases “ran in families”.  Alkaptonuria was the first ...
Patterns of Inheritance for Human Traits
Patterns of Inheritance for Human Traits

... • If you have IAIB as you genes, you have both Type A and Type B blood, also known as Type AB • If you have IAi, i is recessive to IA, so you have type A blood • Q. When would you have Type O blood? • A. When you have ii as your genotype. ...
Document
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... that codes for the protein __________ causes sickle-shaped red blood cells. hemoglobin 22. What is the advantage of being heterozygous for the sickle cell allele? People who were heterozygous are generally healthy and are resistant to malaria. 23. What makes an allele dominant, recessive, or codomin ...
BBHH BBHh
BBHH BBHh

... • Example: In rabbits black coat (B) is dominant over brown (b) and straight hair (H) is dominant to curly (h). Cross a rabbit that is homozygous dominant for both traits with a rabbit that is homozygous dominant for black coat and heterozygous for straight hair. Then give the phenotypic ratio for ...
Mendel and Meiosis - Bishop Ireton High School
Mendel and Meiosis - Bishop Ireton High School

... Red flowers X White flowers =Pink Flowers ...
3-08-10geneticdisordersmeiosis
3-08-10geneticdisordersmeiosis

... represent a cell undergoing meiosis. On the last set of four circles. Refer to page 500 2. Use modeling clay to form 2 pairs of chromosomes about as thick as a pencil. Make one pair longer than the other. ...
Histones
Histones

... around which DNA winds, and play a role in gene regulation. Without histones, the unwound DNA in chromosomes would be very long (a length to width ratio of more than 10 million to one in human DNA). For example, each human cell has about 1.8 meters of DNA, but wound on the histones it has about 90 m ...
Cure/Treatment
Cure/Treatment

... Effects of untreated PKU… • children normal at birth but fail to attain early developmental milestones • microcephaly, progressive impairment of mental function seizures, learning disabilities nd other serious medical problems, Cure/Treatment of PKU… • there is no cure • treatment with restricted di ...
genetic disorder
genetic disorder

... The Disease Condition involving the breakdown and use of fats and cholesterol in the body Harmful amounts of lipids accumulate in the spleen, liver, lungs, bone marrow, and brain Autosomal recessive pattern of inheritance (two copies of the gene must be present) Four variants: A, B, C1, and C2 Clin ...
Chromosomal Basis of Inheritance
Chromosomal Basis of Inheritance

... heterozygous genotype is intermediate in appearance • Codominance: each allele in the genotype for a particular gene will be expressed in the ...
Modern Genetics PPT
Modern Genetics PPT

... Traits Controlled by Single Genes  Many human traits are controlled by a single gene.  These genes have two alleles-dominant and recessive. ...
Modern Genetics
Modern Genetics

... Traits Controlled by Single Genes  Many human traits are controlled by a single gene.  These genes have two alleles-dominant and recessive. ...
Human gene expression and genomic imprinting
Human gene expression and genomic imprinting

... describes heritable states which do not depend on DNA sequence • (Genetic mechanisms explain heritable states (characters) which result from changes in DNA sequences (mutations)) • DNA methylation Gene repression ...
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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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