Ch 6 Inheritance
Gene Disorders
Small Alterations of Proteins Sickle Cell Anemia as an example
"Mutations will affect the genotype, may affect phone type." True or False
True
Alleles
different version of given gene arise by mutation
Incomplete dominance
neither allele is able to exert its full affect ex: medium sized dog
Biochemical Trait
suspility to disease
Allel
version of a gene
Mendel crossed true-breeding pea plants and found the dominant trait always appeared in the F1 generation, but it appeared in a ________ ratio of dominant to recessive in the F2 generation.
3:1
A pea plant is heterozygous for the flower color genes makes gametes. What is the probability that a specific gamete contains the recessive allele for the flower color?
50%
In Mendel's pea plants, yellow seeds are dominant to green seeds. If a true-breeding green- seed-producing plant is crossed to a heterozygous yellow-seed-producing plant, what percentage of offspring produces green seeds?
50%
Mendel's breeding experiments with pea plants indicate that allele of a gene separate during?
Meiosis
The observation that individuals who are deaf also have a heart problem is an example of...
Pleiotropy
Genetic Cross
a controlled mating experiment performed to examine how a particular trait may be inherited
Pleiotropy
a single gene influences a number of different traits
Homozygous
an individual who carries two copies of the same allele
Heterozygous
an individual who carries two different of the same allele
mutation
any change in DNA that makes up a gene
Genetic Traits
any inherited characteristic of an organism that can be observed or detected in some manner
Gene
basic unit of information affecting a genetic trait, formed of chromosomes
Codominance
displayed when the effect of the two alleles is equally viable in the phenotype of the heterozygote ex: gum color is dogs
Polygenic Trait
ex: in humans eye & skin color, running speed, blood pressure,
In Mendel's model of inheritance, what he described as units of inheritance we now refer to as:
genes
Complex Trait
genetic trait who pattern of inheritance cannot be predicted by Mendel's law of inheritance
Why is it important to look at healthy individuals in addition to individuals affected by the disorder
healthy individuals provide baseline for comparison
Example of Incomplete Dominance:
heterozygote cat has medium size body instead of being large or small
Chromosome theory of inheritance
identifies chromosomes as the paired factors that are shuffled and recombined and then separated randomly into sperm and egg cells during meiosis
Being able to use a Punnett Square to track the pattern of inheritance in a two characteristic cross demonstrates Mendel's idea of:
independent assortment
Epistasis
occurs when the phenotypic effect of the alleles of one gene depends on the presence of alleles for another
Dominant
one alley prevents a second allele from affecting the phenotype when the two alleles are paired together
A sperm cell will only contain ___ alleles for a given gene; a skin cell would only contain ___ alleles.
one; two
What was Mendel's primary contribution to our understanding of genetic inheritance?
providing mechanism that explains patterns of inheritance
If two different allele for the same trait have an equal affect on the phenotype, the allele are...
recessive
Punnett Square
shows all possible ways two alleles can be brought together through fertilization
Law of Segregation
states that the two alleles of a gene are separated during meiosis and end up in different gametes (egg or sperm)
Law of Independent Assortment
states that when gametes form, the two copies of any given gene segregation during meiosis independently of any other genes
F Generation
the first generation of offspring
P Generation
the first set of parents
Genome
the haploid set of chromosomes in a gamete or microorganism, or in each cell of a multicellular organism.
Why did Mendel analyze thousands of plants while conducting his research?
the likelihood of of seeing a clear pattern is higher with a larger data set
The chance of a parent passing on a given allele to a chid is ...... each time they have another child
the same
Chromosomes
thread-like molecules made of DNA and proteins
Mendelian Traits
traits controlled by a single genes and unaffected by environmental conditions
Polygenic
traits controlled by actions of multiple genes