A term that describes two chromosomes "exchanging" material for variation.
The main component of all chromosomes is a polymer known as _____.
The sex of the offspring is determined on the _____ chromosome.
Chromosomes 1-22 are called _____.
What is a gene?
An individual who has two different alleles for a gene is _____.
If an allele does not affect the phenotype of a heterozygous individual, the allele is _____.
A striped fruit fly is crossed with a non-striped fly. N=non-striped is dominant, n=striped is recessive What is the genotype of the striped parent?
A striped fruit fly is crossed with a non-striped fly. All 100 offspring are non-striped. N=non-striped is dominant, n=striped is recessive What is the genotype of the non-striped parent?
What is an allele?
An individual who has two identical alleles for a gene is _____.
What does it mean if an allele is dominant?
The 'B' gene controls the color of a dog's coat. The 'R' gene controls the texture. Which alleles (B, b, R, and/or r) would occur in all the offspring of the following parents? BbRR x bbRr
The 'B' gene controls the color of a dog's coat. The 'R' gene controls the texture. (B=black-dominant, b=white-recessive, R=rough-dominant, r=smooth-recessive) Which trait would occur in all the offspring of the following parents? bbRR x BbRr
What types of cells are produced by meiosis?
When a haploid sperm fertilizes a haploid egg, they produce a _____ zygote.
What problem would result if sperm and eggs were produced by mitosis instead of meiosis?
State two differences between meiosis and mitosis.
The law of independent assortment describes the inheritance of genes on different chromosomes and the behavior of chromosomes at the beginning of a) meiosis 1, b) meiosis 2, c) mitosis, d) all of the above
In a heterozygous individual, the _____ allele determines the phenotype.
If a heterozygous individual has a phenotype that is intermediate between both types of homozygous individuals, the two alleles show _____ _____.
Genetics is the study of _____.
Traits are characteristics that can be passed only from a _____ organism to its _____.
The process in which traits are passed from parents to offspring is called _____.
Each cell of a Punnett square represents one possible _____ outcome for any offspring of two specific parents.
Genotype refers to the _____ make-up of an organism.
_____ is the physical trait that is expressed in an individual.
_____ are the different forms of a gene for any given trait.
For each trait, there are _____ allele possibilities.
When the expression of one allele is masked by the presence of another, it is said to be _____.
When an allele masks the presence of another allele, it is said to be _____.
When both alleles of a parent of offspring are identical, one is said to be _____.
A heterozygous genotype is when the alleles present are _____, such as Bb.
The female's genes should usually b e placed along the _____ side of the Punnett square.
It is proper to put the _____ allele before a recessive allele when determining the genotype of the offspring in a Punnett square.
For an offspring to _____ a recessive trait, both parents must have at least one _____ allele in their genotype.
Type AB blood is an example of _____.
A child has a genetic disease caused by a single gene. Neither parent has the disease. The allele that causes the genetic disease is _____.
An allele of a single gene causes a disease that affects many more males than females. This allele is a) autosomal dominant b) autosomal recessive c) X-linked dominant d) X-linked recessive
A daughter inherits a) more genes from her mother b) more genes from her father c) one copy of each gene from her mother and one copy from her father
A man who is heterozygous for the albino allele is married to a woman who is homozygous for normal skin color (Aa x AA). What fraction of their children would you expect to be albino?
If a son has an X-linked condition (e.g. color b lindens or hemophilia), he must have inherited the gene for this condition from his _____.
A mother has type 0 blood and her husband has type AB blood. What blood types can their children have?
Parents who are both heterozygous for the alleles for albinism (Aa x Aa) have two heterozygous children. Now, the mother is expecting fraternal twins. The most likely genotypes for these twins are _____ and _____.
What is the process called where traits are passed from one generation to the next?
Mendel's idea that "elements" separate during gamete formation is called the law of _____.
The allele that masks the effects of the other is ____ and the masked allele is ____.
True-breeding plants are always _____.
A true-breeding tall plant is crossed to a true-breeding dwarf plant. The offspring in the F1 generation are all tall plants. The F1 generation is then crossed to yield a F2 generation. What is the phenotypic ratio of the F2 generation?
3 tall : 1 dwarf
Mendel's law of ____ states that a random assortment of maternally and paternally derived chromosomes in meiosis results in gametes that have different combinations of alleles.
Mendel's laws are explained by _____.
chromosome behavior in meiosis
Consider a group of 100 individuals (50 couples), all of whom carry a recessive disease allele. If 200 children were born to these couples, what percentage of the children would, theoretically, be heterozygous carriers like their parents?
Which genotype is normally not found in a gamete? a) AB, b) Ab, c) aa, d) ab
Which of the following crosses is a test cross? a) unknown x AA, b) unknown x Aa, c) unknown x aa, d) unknown x unknown
unknown x aa
What term describes the most common expression of a particular allele combination in a population? a) dominant, b) recessive, c) genotype, d) wild type
A test cross is conducted between an individual with a dominant phenotype, but unknown genotype, and a homozygous recessive individual. The phenotypes of the offspring are 50% dominant and 50% recessive. What was the genotype of the unknown parent?
Kathy's brother has cystic fibrosis. Her husband has no family history of CF. What is the chance that Kathy's child has inherited the cystic fibrosis allele and is a carrier of the CF mutation?
2/3 x 1/2 = 1/3
The occurrence of affected individuals in every generation in a family suggests ____ trait.
an autosomal dominant
Which of the following incorrectly identifies the mode of inheritance for the given genetic disease? a) Tay-Sachs disease - recessive, b) cystic fibrosis - recessive, c) Huntington disease - dominant, d) sickle cell - dominant
sickle cell - dominant
Consider an autosomal dominant trait. If an unaffected parent and an affected heterozygous parent are expecting, what is the chance of them having an unaffected child?
Two phenotypically normal individuals have an affected child. What can we conclude about the parents?
They both carried the disease allele.
Relatives who have children together have a much higher risk of having children affected by a(n) ____ condition.
Achondroplasia is a dominant form of dwarfism. Two affected individuals have a ____ chance of having an unaffected child.
Recessive alleles _____. a) appear to skip generations, b) have disorders that are typically more severe, c) produce symptoms at earlier ages, d) all of the above
all of the above
Which of the following is a characteristic of an autosomal dominant trait? a) both males and females may be affected, b) males and females transmit the disease with equal frequency, c) successive generations are affected, d) all of the above
all of the above
In the cross AaBb x aabb, what percentage of the offspring are expected to show a dominant phenotype for both traits?
Two genes on the same chromosome can appear to assort independently if _____.
they are located very far apart from each other
Can independent assortment be demonstrated in a monohybrid cross?
No, you must examine the transmission of two or more genes.
Which of the following is an example of a cross between two dihybrids? a) AaBb x aabb, b) AaBb x AaBb, c) aabb x AABB, d) aabb x aabb
AaBb x AaBb
Which of the following phenotypic results is expected from a cross between two dihybrids? a) 1:1:1:1 ratio, b) 9:3:3:1 ratio, c) all dominant for both traits, d) all recessive for both traits
Mendel's ____ states that for two genes on different chromosomes, the inheritance of one does not influence the chance of inheritance for the other.
law of independent assortment
Albinism is an autosomal recessive trait. Two carriers of albinism have four children. One of their children is albino and the remaining three are normally pigmented. What is the probability that their next child will be albino?
Family relationships are displayed using _____.
A diploid individual with two identical alleles of a gene is ____, while a ____ has two different alleles of a gene.
A ____ can be used to follow the transmission of alleles and is based on probability. It represents how particular genes in gametes come together, assuming they are carried on different chromosomes.
In pea plants, tall is dominant to short. Which of the following would be the genotype of a heterozygous tall plant?
Sickle cell anemia is a recessive trait. A woman with sickle cell anemia disease has a child with a homozygous normal man (with no family history of sickle cell disease). What is the probability that this couple will have a homozygous normal child?