Genetics
Alleles- having different forms of the same gene.
Phenotypes- physical characteristics of an organism.
Homozygous- having the same alleles for a trait. (identical)
Heterozygous- having different alleles for a trait.
Dominant- the allele form that always expresses itself over another form.
Gene- piece of DNA that tells about a specific trait.
Chromosomes- strands of DNA and protein.
Genotype- the specific genes an organism has.
Gregor Mendel- used pea plants to study the inheritance of traits.
Gregor Mendel- reacted the conclusion that traits are- inherited the factors that
pass from parents to offspring.
In Mendel’s garden peas, round peas (R) are dominant to wrinkled peas (r) . If two
heterozygous round pea plants are crossed what are the possible genotype’s of
the offspring? RR,Rr,rr
Dominant allele- O (capital letter)
Recessive allele-o (lowercase)
Hybrid Oo
Homozygous Dominant OO
Homozygous Recessive oo
Heterozygous- Oo
The letters along the left side and top of a punnett square represent each parent’s
alleles.
The letters inside the squares of a punnett square represent? The possible
genotypes of the offspring.
Which of the following is NOT shown on a punnett square? The actual results of a
genetic cross.
In humans the diploid number is 46.
If a cell contains two alleles for each trait, it is diploid
The “backbone” of DNA is made of- phosphate molecules and deoxyribose sugars.
Adenine bonds with thymine
Cytosine bonds with guanine
A portion of a DNA strand has the bases given below. Which of the following
bases would form the complement to this strand CTGGTA? GACCAT
Which of the following is found in RNA but not DNA? Uracil
In Mendel’s pea plants, the trait for yellow peas was dominant , Y and the trait for
the green peas was recessive , y. The following show possible genotypes for pea
color except. yy
A pink snapdragon plant is crossed with a red snapdragon plant. What percent of
the offspring can be predicted to have white flowers? 0%
In fruit flies, straight wings (S) are dominant, and curled wings (s) are recessive. A
fruit fly with a genotype of Ss is crossed with a fruit fly with a genotype of ss. If
the parent flies have 20 offspring, about how many will have curled wings? 20
DNA fingerprinting works because- no two people, expect identical twins, have
exactly the same DNA.
In guinea pigs, brown fur is dominant to white fur. To determine if a female
guinea pig is heterozygous or homozygous, it should be crossed with a male
guinea pig known to have which of the following genotypes? Homozygous white