Module #8 Review Questions Flashcards
What term is used if an organism has a certain characteristic that is always passed on to its offspring we say that this organism bred true with respect to that characteristic?
True Breeding
What is one of a pair of genes that occupies the same position on homologous chromosomes?
Allele
What is an allele that will not determine the phenotype unless the genotype is homozygous in that allele?
Recessive allele
What is a cross between two individuals, concentrating on only one definable trait?
Monohybrid cross
What is a cross between two individuals, concentrating on two definable traits?
Dihybrid cross
What is the inheritance of a genetic trait not on a sex chromosome?
Autosomal inheritance
There are four principles in Mendal’s updated terminology, name all four of them.
- The traits of an organism are determined by its genes
- Each organism has two alleles that make up the genotype for a given trait
- In sexual reproduction, each parent contributes only one of its alleles to its offspring.
- In each genotype, there is a dominant allele. If it exists in an organism, the phenotype is determined by that allele.
A diagram that follows a particular phenotype through several generations is call ___.
A pedigree
Some traits are sex-linked, which means the alleles that define those traits are found where?
On the Sex chromosomes
Chromosomes that do not determine the sex of an individual are called what?
Autosomes
Many traits are caused by the interaction of several genes. This is called what?
Polygenetic inheritance
What is the term that means the alleles tend to “mix” rather than one dominating the other?
Incomplete dominance
In some cases, one set of alleles might affect how another set of alleles is expressed. What is this called?
Epistasis
What is it called when a single gene can affect multiple observable traits?
Pleiotrophy
The human gene for blood type which has A, B, and O alleles is an example of what kind of alleles.
Multiple
In blood type, A and B are dominant over O but not dominant over each other, this is an example of what?
Codominance
When an antigen is introduced into the blood, the body’s response is to produce what?
An Antibody
The “+” and “-“in the blood type refers to the what, which is controlled by a single gene with two alleles?
Rh factor
The “+” and the “-“ refer to the RH factor in the blood. Which allele is dominant?
“+”
The “+” and the “-“ refer to the RH factor in the blood. Which allele is recessive?
“-“
In Mendal’s experiments, he determined that the allele for tallness (we’ll call it “T”) is dominant whereas the allele for shortness (we’ll call it “t”) is recessive. Let’s suppose a homozygous tall pea plant was crossed with a heterozygous pea plant. What will be the genotype and phenotypes of the offspring?
50% will have the genotype TT while 50% have the genotype Tt. 100% will have the phenotype of being tall.
he allele for a pea plant to produce yellow peas(Y) is dominant over the allele for green peas (y). A heterozygous pea plant is crossed with a pea plant that produces green peas. What is the percent chance of each genotype and phenotype produced by this union?
50% will be Yy and will make yellow peas, while 50% will be yy and will make green peas.
In Pea plants tallness is a dominant genetic trait if “T” represents the dominant allele and “t” represents the recessive allele, what are the possible genotypes for a plant is tall.
TT, Tt
A woman is heterozygous in the ability to roll her tongue when extended. If she marries a man who cannot roll his tongue, what percentage of their children will be able to roll their tongues? Remember, the allele for being able to roll your tongue is dominant.
50% of the children will be able to roll their tongues.
For a given trait, how many alleles does a normal gamete have?
One allele for each trait. That way, when two gametes fertilize each other the zygote will have two alleles for each trait.
For a given trait, how many alleles does a non-gamete cell have?
Two alleles
From experiment 8.3 what percentage of the girls will have the disease?
0% of the girls will have the disease
From experiment 8.3. What percentage of the boys will have the disease?
50% of the boys will have the disease.
Eye color in fruit flies is a sex-linked trait. Red (R) is dominant; while white (r) is recessive. If a red-eyed male and a white-eyed female are crossed, what percentage of males and females are red-eyed?
100% female are red eyed and 100% males are white eyed.
A genetic abnormality that is passed through the autosomes is called what?
Autosomal inheritance
A genetic abnormality is passed through the sex chromosomes is called what?
Sex-linked inheritance
When one of the alleles of a gene is chemically changed this is called what?
Allele mutation
What is a situation in which a chromosome loses or gains genes during meiosis?
Change in the chromosome structure
hat is a situation in which a cell can wind up with too many or too few of a specific chromosome.
Change in the chromosome number
In pea color and pea texture, yellow (Y) is dominant and green (y) is recessive. In addition, smooth peas (S) are dominant and wrinkled peas (s) are recessive. A pea plant that produces green peas and is heterozygous in pea texture is crossed with a plant that is heterozygous in pea color and produces wrinkled peas. What are the percentages of the phenotypes in the offspring?
25% will produce yellow, smooth peas, 25% willproduce yellow, wrinkled peas, 25% will produce green, smooth peas, and 25% will produce green, wrinkled peas.
In a pedigree both parents can roll their tongue and produce 3 offspring that can roll their tongue and one that cannot. What is the dominant trait?
Able to roll the tongue
n a pedigree both parents can roll their tongue and produce 3 offspring that can roll their tongue and one that cannot. What are the genotype of the parents?
the inability to roll the tongue is recessive. Both of the first parents (1 and 2) must be Rr and Rr. 3 must be rr,4 is Rr
A man that has A+ blood and is heterozygous in each allele marries a woman whose blood is AB-. What are the possible blood types for their children, along with the percentage chance of each?
25% of the children will have A+ blood, 25% of the children will be A-, 12.5% will be AB+, 12.5% will be AB-, 12.5 will be B+ and 12.5% will be B-
