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Genetics. Various forms of a gene at a given locus are called: Alleles Mendel chose …… plants as his test subject. Pea. If A is dominant to a, the genotypes AA and Aa have the same: Phenotype. The F 2 phenotypic ratio of a monohybrid cross is: 3:1 The phenotypic ratio of a testcross is:
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Various forms of a gene at a given locus are called: • Alleles • Mendel chose …… plants as his test subject. • Pea
If A is dominant to a, the genotypes AA and Aa have the same: • Phenotype. • The F2 phenotypic ratio of a monohybrid cross is: • 3:1 • The phenotypic ratio of a testcross is: • 1:1
The F2 phenotypic ratio of a dihybrid cross is : • 9:3:3:1 • B is dominant to b, The cross Bb X bb is called: • Testcross.
PKUTEST • This disease is known to be caused by an: • Autosomal recessive gene.
DMD: Duchenne Muscular Dystrophy • How a boy with DMD rises • DMD is an ………. trait in humans. • X-linked recessive. • What is the genotype of a normal man whose brother has DMD?
X (D) Y • Can this man be a carrier? • NO • If he marries a normal woman X (D) X (D), what is the probability that their children will have DMD? • O%
Nicolas, Czar of Russia (right), married Alexandra (left), granddaughter of Victoria of England (1819-1901). Alexis inherited the hemophilia allele and suffered serious bleeding.
Colorblindness • Colorblindness is an …...trait in humans. • X-linked • A colorblind woman has the following genotype (the gene is designated by D): • X(d) X (d) • If this woman marries a normal man: • their ……. will be colorblind, …… will be carriers.
Down Syndrome:Trisomy 21 wasfirst described in 1866 by J. Langdon Down
Syndrome means: • A set of symptoms that occur together. • The sex chromosome composition of a person with Klinefelter syndrome is: • XXY • The sex chromosome composition of a person with Turner syndrome is: • XO
Correlation between maternal age and the incidence of Down syndrome • As women age, the chances they will bear a child with Down syndrome increase
A chromosome’s gene sequence that was ABCDEFGH before damage and ABCFG H after is an example of: • Deletion
A chromosome’s gene sequence that was ABCDEFGH before modification and ABCDLMNOP afterward is an example of: • Translocation • A chromosome’s gene sequence that was ABCDEFGH before modification and ABCDCDCDEFGH afterward is an example of: • Duplication
A chromosome’s gene sequence that was ABCDEFGH before damage and ABFEDCG H after is an example of: • Inversion
Bacteriophages are: • Viruses • In DNA, complementary base pairing occurs between: • Adenine and thymine, guanine and cytosine A-T pairs and G-C pairs • If cytosine makes up 15% of the bases in a DNA molecule. The base A makes up what proportion of the bases?
35% • In the pairing of two nucleotides within the double helix: • Hydrogen bonds are used. • The base order of one strand of a DNA molecule is: 5’ G A A T T C 3’ what is themost likely sequence of the other strand? • 3’ C T T A A G 5’
If the codon that specifies an amino acid is AUA, the base sequence of the anticodon is: • UAU • Genetic information flows: • DNA RNA Protein • Transcription Translation
A change in the sequence of DNA bases (mutation) results in a change in the sequence of bases in mRNA, which can result in a change in the sequence of amino acids in a polypeptide chain. These changes can destroy the functions of proteins (products of genes).