GEN BIO AMELIORATE Flashcards
detect certain conditions produced by genes
Genetic testing –
– the study of genes and their transmission from one generation to the next
Genetics
– location of a specific pair of genes
Gene locus
– DNA sequences that contain instructions for building proteins
Genes
– the complete genetic material of an organism along with its noncoding nucleic acid sequence
Genome
– a cellular structure consisting of one DNA molecule and associated protein molecules
Chromosomes
- complete set of alleles inherited from parents
Genotype
- observable physical and functional traits
Phenotype
● Two identical alleles at a particular locus
Homozygous Chromosomes
● Two different alleles at a particular locus
Heterozygous Chromosomes
● Masks or suppresses the expression of its complementary allele
● Always expressed even if heterozygous
Dominant Allele
● Will not be expressed if paired with a dominant allele (heterozygous)
● Will only be expressed if individual is homozygous for the recessive allele
Recessive Allele
Worked with pea plants in the 1850s
in Austria and did multiple genetic experiments to develop basic inheritance rules.
Gregor Mendel
● Father of modern genetics
Gregor Mendel
Gregor Mendel rules
- Law of Segregation
- Law of Independent
Assortment - Law of Dominance
● Gametes carry only one allele of each gene
● The dominant and recessive or any
other pairings will eventually separate
Law of Segregation
● Dominant will always be expressed
● Recessive will only be expressed if it’s
homozygous
Law of Dominance
● Crossing of 2 traits
Dihybrid Cross
● Crossing of 1 trait
Monohybrid Cross
● Genes for different traits are separated from each other independently during meiosis – crossing over
● This applies only if the two genes in questions are on different chromosomes
Law of Independent Assortment
● A table in which all of the possible outcomes for a genetic cross between two individuals with known genotypes are given
Punnett Square
Both alleles of a gene at a locus are partially expressed
Dominant – Red
Recessive – White
Offspring – Pink
incomplete
The dominant
overpowers recessive
Dominant – Red
Recessive – White
Offspring – Red
Complete
– failure of homologous chromosomes or sister chromatids to separate properly
Nondisjunction
Both alleles are expressed equally
Dominant – Red
Recessive – White
Offspring – Red & White
Co-dominance
● Trisomy 21 – extra copy of chromosome in the 21st chromosome in the karyotype
mental development is retarded
Down Syndrome (47, 21+)
● Monosomy – absence of one member of a pair of chromosomes
● AllorpartofoneX
chromosome
is
absent ● Short
stature, neck, rudimentary ovaries,
webbed
underdeveloped breasts, broad-shield-like chest
turner Syndrome (45, XO)
A taller, less muscular body than males their age
● Broader hips and longer legs, larger breasts, weaker bones, a smaller penis, and testicles, less facial and body
hair following puberty
● Lower energy level, delay in puberty or go a parcel amount
Klinefelter Syndrome (47, XXY)
● Extremely tall, no facial and body hair, breast development
● Osteoporosis, feminine fat distribution, small testis
Jacob Syndrome (47, XYY)
● Total chromosomes: 47
● 21+: +1 in the 21st pair of
chromosomes
Down Syndrome (47, 21+)
Total chromosomes: 47
XXY: extra X copy of chromosome
Klinefelter Syndrome (47, XXY)
Total chromosomes: 45
XO: 0 chromosome (absent)
Turner Syndrome (45, XO)
Total chromosomes: 7
XYY: extra Y copy of chromosome
Jacob Syndrome (47, XYY)
– a piece of a chromosome breaks off
Deletions
– a piece of chromosome breaks off and attaches to a different chromosome
Translocations
