• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Biol-1406_Ch12Notes.ppt
Biol-1406_Ch12Notes.ppt

... • Presence of a particular allele does not ensure its encoded trait will be expressed in an individual carrying that allele. – ___________ - Totality of alleles. – ___________ - Physical appearance. ...
Lecture 5
Lecture 5

... the alleles governing yellow body and brown body, respectively; w and w+ for alleles for white eye and red eye; and Y for the Y chromosome. ...
Homologous chromosomes
Homologous chromosomes

... All other human cells have 46 chromosomes. ­If cells only reproduced through mitosis then when an  egg cell and a sperm cell fuse, the new cell would have 92  chromosomes! Meiosis is the type of cell division that produces gametes  with half the number of chromosomes as a parent's body  cells. ­Two  ...
Genetics - Biology Junction
Genetics - Biology Junction

... H. Testing for Genetic Disorders (Science Focus box) 1. Two genetic disorders resulting from faulty genes are Huntington disease and cystic fibrosis. 2 Researchers are tests that can detect particular DNA base sequencing that may be able to identify individuals who may either have a genetic disease ...
AG2010 lecture 1_basic genetics
AG2010 lecture 1_basic genetics

... • Grant/grant/grant…start early. • Homework due dates will be noticed on website. • Question sessions before and after homework due every Thursday after class: covered contents are by request. ...
7.2 D: Genes and Alleles
7.2 D: Genes and Alleles

... b. Even though a gene has multiple alleles, a person can only have two alleles for that trait. c. Traits controlled by many genes have a wide range of phenotypes. 2. Match each example to the pattern of inheritance. a. ______Human blood type 1. Single gene with two alleles ...
The Biology of Human Sex Differences
The Biology of Human Sex Differences

... Y chromosomes.20 The X chromosome contains about 5 percent of the DNA in the human genome. The Y chromosome not only is less than half this size but also has a long heterochromatic portion of the long arm that is noncoding. The striking inequality of the two X chromosomes in women as compared with t ...
Human Inheritance
Human Inheritance

...  With treatment, patients can survive into adulthood.  Most common _fatal___ genetic disorder in the _United States____ among Caucasians. 3. Phenylketonuria or _PKU___  Characterized by an inability to breakdown the amino acid, _phenylalanine_____.  If untreated, results in severe mental retarda ...
So you say you want extra credit…
So you say you want extra credit…

... co-dominant alleles-Two different alleles at a locus are responsible for different phenotypes, and both alleles affect the phenotype of the heterozygote. For example, consider the situation where there are three alleles A,B, and O that determine human blood type.  autosomal- A locus on any chromoso ...
Preferential X-chromosome inactivation, DNA
Preferential X-chromosome inactivation, DNA

... a PGK-IA male, showing the position of the testis-speeific autosome-coded PGK-2. Data from Harper etal. (1982). affect inactivation and imprinting in general, we must investigate the early developing embryo. Changes in Xchromosome activity may be monitored by the use of highly sensitive microassays ...
Unit IX Teacher Notes
Unit IX Teacher Notes

... human somatic cell has __46__chromosomes, or 23 pairs of chromosomes. Of these 23 pairs, 22 pairs are called __homologous__pairs, meaning they contain the same genes in the same order. The 44 chromosomes that make up the 22 homologous pairs in each cell are called _autosomes_______. The 23rd pair of ...
chromosomal
chromosomal

... Karyotype cont’d • Each of an individual’s 46 chromosomes has thousands of genes so the presence of all chromosomes is essential for normal functioning – Humans who are missing a chromosome don’t survive – Humans with more than two copies of a chromosome, called trisomy, may survive but will not de ...
Unit IX Teacher Notes 2017
Unit IX Teacher Notes 2017

... human somatic cell has __46__chromosomes, or 23 pairs of chromosomes. Of these 23 pairs, 22 pairs are called __homologous__pairs, meaning they contain the same genes in the same order. The 44 chromosomes that make up the 22 homologous pairs in each cell are called _autosomes_______. The 23rd pair of ...
Human Heredity
Human Heredity

... A change in just one DNA base for the gene that codes for the protein _____________ causes sickle–shaped red blood cells. What is the dense region in the nucleus that is formed by the turned-off X chromosome? True or False: Barr bodies are found only in males. If you saw a white cat with orange and ...
Mendel’s Laws: Breaking the Law
Mendel’s Laws: Breaking the Law

... Let the letters represent alleles for real world traits to make the process more tangible. ...
CHAPTER 6
CHAPTER 6

... This is similar to imprinting. Also, once X inactivation occurs during embryonic development, it is remembered throughout the rest of the life of the organism, which is also similar to imprinting. X inactivation in mammals is different from genomic imprinting, in that it is not sex dependent. The X ...
1-. During the first meiotic division (meiosis 1), (A) homologous
1-. During the first meiotic division (meiosis 1), (A) homologous

... gene linkage. If genes are linked, they are located on the same chromosome an are more likely to segregate together into the same cell. I 13. (C) is correct. Recall that a dihybrid cross between two heterozygotes pro-duces a 9:3:3: 1 offspring ratio. The question is asking for one of the heterozygot ...
Explanations for males with MECP2-related
Explanations for males with MECP2-related

... unrelated events. Because these males have two copies of the X chromosome and undergo the same process of X inactivation that is seen in females, these males present with a clinical presentation that is very consistent with the classic Rett syndrome presentation. These males, will in addition to hav ...
Chromosomes - Fall River Public Schools
Chromosomes - Fall River Public Schools

... Directions: Read the following text and then raise your hand to map your chromosomes to match the description in the text. You will then present your map to the class as a group. Eukaryotic cells are more complex than prokaryotic cells are. The chromosomes of eukaryotic cells contain more DNA than t ...
Cell Cycle & Cell Division
Cell Cycle & Cell Division

... TheThe process of organizing and condensing long strands of DNA into compact form takes place when? What are the group of proteins called that organizes and condenses the long strands of DNA into tight coils? ...
Genetics - TeacherWeb
Genetics - TeacherWeb

... • Trait - variations of a gene: (i.e. black or brown hair) determined by alleles • Allele – different forms a gene, often expressed as Y or y, X or x, Z or z • Gene - a heritable feature on a chromosome: (i.e. hair color) ...
Mendel & Heredity
Mendel & Heredity

... Represents the genotype of an offspring Probability – the likelihood that a certain event will occur. ...
1 - Humble ISD
1 - Humble ISD

... 24. ______ Autosomal recessive disorder associated with faulty chloride channels; abnormal mucus production 25. ______ Autosomal recessive disorder characterized by inability to metabolize phenylalanine; controlled by diet 26. ______ Term used to describe mutated allele when normal allele protein pr ...
BioSc 231 Exam 1 2005
BioSc 231 Exam 1 2005

... Purple flower color in peas is dominant to white. Assume that Mendel conducted a series of experiments where plants with purple flowers were crossed with plants with white flowers and the following progeny were produced: 325 purple flowers and 350 white flowers. What is the most probable genotype of ...
Mendelian Genetics
Mendelian Genetics

... 4) Describe the relationship between genes, chromosomes, and DNA. Describe what a trait is and what the relationship is between traits and genes 5) Describe what an allele is. Also explain what is meant by the terms dominant and recessive alleles. 6) Explain and use examples to show the differences ...
< 1 ... 121 122 123 124 125 126 127 128 129 ... 241 >

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.
  • studyres.com © 2026
  • DMCA
  • Privacy
  • Terms
  • Report