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