Podcast
Questions and Answers
During which stage of meiosis do sister chromatids move to opposite poles?
During which stage of meiosis do sister chromatids move to opposite poles?
- Metaphase II
- Anaphase II (correct)
- Prophase I
- Telophase II
What is the result of crossing over between two non-sister chromatids of homologous pairs?
What is the result of crossing over between two non-sister chromatids of homologous pairs?
- Homologous chromosomes have only paternal genes
- Homologous chromosomes have only maternal genes
- Individual chromosomes have both paternal and maternal genes (correct)
- Sister chromatids are identical
How many diploid combinations are possible due to independent assortment in humans?
How many diploid combinations are possible due to independent assortment in humans?
- 8.4 million
- 23
- 70 trillion (correct)
- 4,096
What is the term for the process by which homologous pairs line up randomly during metaphase I?
What is the term for the process by which homologous pairs line up randomly during metaphase I?
Which stage of meiosis follows Anaphase II?
Which stage of meiosis follows Anaphase II?
What is the approximate number of possible gamete combinations due to independent assortment in humans?
What is the approximate number of possible gamete combinations due to independent assortment in humans?
What is the primary function of histone proteins in the organization of genetic material?
What is the primary function of histone proteins in the organization of genetic material?
What is the term for the thread-like structures that form during cell division?
What is the term for the thread-like structures that form during cell division?
What is the term for the number of chromosomes present in a species?
What is the term for the number of chromosomes present in a species?
What is the region known as, where chromosomes pinch in during cell division?
What is the region known as, where chromosomes pinch in during cell division?
What is the term for the study of the number and structure of chromosomes in a species?
What is the term for the study of the number and structure of chromosomes in a species?
What is the term for the genetic information stored in DNA?
What is the term for the genetic information stored in DNA?
What is the result of nondisjunction of sex chromosomes in females?
What is the result of nondisjunction of sex chromosomes in females?
What is the purpose of chorion villus sampling?
What is the purpose of chorion villus sampling?
During which phase of meiosis is genetic variation introduced?
During which phase of meiosis is genetic variation introduced?
What is the purpose of amniocentesis?
What is the purpose of amniocentesis?
What is the result of nondisjunction of sex chromosomes in males?
What is the result of nondisjunction of sex chromosomes in males?
What is the incidence of XXX Females?
What is the incidence of XXX Females?
Flashcards
Turner Syndrome
Turner Syndrome
A genetic condition where females have only one X chromosome (XO). This causes underdeveloped female sex characteristics.
Klinefelter Syndrome
Klinefelter Syndrome
A genetic condition where males have an extra X chromosome (XXY). This leads to higher levels of female sex hormones, more developed female sex characteristics, and sterility.
Jacobs Syndrome
Jacobs Syndrome
A genetic condition where males have an extra Y chromosome (XYY). This results in slightly taller stature and slightly lower intelligence.
XXX Females
XXX Females
Signup and view all the flashcards
Chorion Villus Sampling (CVS)
Chorion Villus Sampling (CVS)
Signup and view all the flashcards
Amniocentesis
Amniocentesis
Signup and view all the flashcards
Mitosis
Mitosis
Signup and view all the flashcards
Meiosis
Meiosis
Signup and view all the flashcards
Chromosome
Chromosome
Signup and view all the flashcards
Histones
Histones
Signup and view all the flashcards
Centromere
Centromere
Signup and view all the flashcards
Homologous Chromosomes
Homologous Chromosomes
Signup and view all the flashcards
Alleles
Alleles
Signup and view all the flashcards
Crossing Over
Crossing Over
Signup and view all the flashcards
Independent Assortment
Independent Assortment
Signup and view all the flashcards
Random Fertilization
Random Fertilization
Signup and view all the flashcards
Study Notes
Chromosomal Abnormalities
- Turner Syndrome (XO): underdeveloped female sex characteristics
- Klinefelter Syndrome (XXY Males): high levels of female sex hormones; more developed female sex characteristics; sterile
- Jacobs Syndrome (XYY Males): somewhat taller; below average intelligence
- XXX Females (1:1000 live births): healthy and fertile; karyotype determines
Prenatal Screening for Genetic Disorders
- Chorion Villus Sampling (Biopsy): cells from the outer membrane of the embryo are removed for karyotyping to detect chromosomal disorders; can be done as early as 8 weeks into pregnancy
- Amniocentesis: amniotic fluid containing cells from the fetus is drawn to prepare and analyze karyotypes for chromosomal abnormalities
Mitosis and Meiosis
- Genetic variation is introduced during Prophase I and Metaphase I
- Chromatin condenses into visible chromosomes during cell division
- Histones act as spool, wrapping DNA to fit in the nucleus
- Chromosome = DNA and associated proteins
- Centromere: the pinched region on a chromosome
Organization of Genetic Material
- Genetic information is stored in DNA (deoxyribonucleic acid)
- Chromosomes are found in the nucleus
- Histones wrap DNA, allowing it to fit in the nucleus
Chromosome Number
- Humans have 46 chromosomes: 22 pairs of homologous chromosomes (autosomes) and 2 sex chromosomes (XX or XY)
- Different species have different numbers of chromosomes
Alleles and Homologous Chromosomes
- Homologous chromosomes carry the same genes at the same location (locus)
- Alleles: different "flavors" of the same gene
- Each side's microtubules on a kinetochore of one replicated chromosome separate during Anaphase II
Meiosis
- Meiosis results in genetically distinct daughter cells
- Crossing over: occurs between two non-sister chromatids of homologous pairs
- Independent assortment: occurs in Metaphase I, where homologous pairs line up randomly
- Random fertilization: 2 gametes combine, resulting in 70 trillion diploid combinations with crossing over
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
