BIO 1500 Chapter 14

85% of the population is Rh ____

+

Rh___ blood can never be given to someone with Rh ____ blood, but the other way around works. For example, 0 Rh+ blood can not be given to someone with the blood type AB Rh - .

+, -

Why are pea plants a good organism to use for genetic experiments? (6 reasons)

1.Inexpensive 2.Short lifetime 3.many observable traits 4.lots of progeny 5.self-fertilizing 6.can be cross-fertilized

What is the Phenotypic ratio of a Dihybrid Cross?

9:3:3:1

Fertilization

A chance event, with a number of possible outcomes that could be predicted based on probability

Punnett Square

A chart that helps to visualize the probability of different outcomes in a genetic cross.

Pedigree

A family tree that describes the interrelationships of parents and children across generations

Epistasis

A gene at one locus alters the phenotypic expression of a gene at a second locus

Character

A heritable feature that varies among individuals (such as flower color)

__________ is a form of dwarfism caused by a rare dominant allele

Achondroplasia

________ is a recessive condition characterized by a lack of pigmentation in skin and hair

Albinism

________ is an example of epistasis

Albinism

As with the ABO system, there is a dominant ______ which happens to be the positive family. This means that the genetic pairs that can exist in humans are as follows: ______ and _______.

Allele, Genetic Makeup and Blood Type

Three pairs of genes are the same thing as three pairs of what?

Alleles

What segregates during gamete production?

Alleles

Polygenic inheritance

An additive effect of two or more genes on a single phenotypic character

Phenotype

An individual's observable physical traits (purple flower, white flower)

Dry ear wax produced when allele codes for _______

Arginine

The cystic fibrosis allele results in defective or absent chloride transport channels in plasma membranes leading to a buildup of _______ ions inside the cell

Chloride

What are autosomes?

Chromosomes 1-22

What (i.e., matings between close relatives) increases the chance of mating between two carriers of the same rare allele?

Consanguineous matings

Symptoms of this particular disease include mucus buildup in some internal organs and abnormal absorption of nutrients in the small intestine (pleiotropy)

Cystic Fibrosis

For example, pleiotropic alleles are responsible for the multiple symptoms of certain hereditary diseases, such as ________ ________ and ________-_________ disease

Cystic fibrosis, sickle-cell

What number do chromosomes of somatic cells contain?

Diploid number (2n)

Some human disorders are caused by _________ alleles

Dominant

Alleles can either be ________ or _________.

Dominant or recessive

Trait

Each variant for a character, such as purple or white color for flowers

Another departure from Mendelian genetics arises when the phenotype for a character depends on ________ as well as genotype

Environment

The first offspring produced from a monohybrid cross is called the ______ ______________

F1 generation

F1 =

First generation of offspring (first filial)

The _______ _______ of the offspring can be used as evidence of how hereditary information might be passed to them from each parent plant.

Flower colors

What is the genetic composition of an organism called?

Genotype

Wet ear wax produced when allele codes for _______ (amino acid)

Glycine

Who is known as the 'founder' of genetics?

Gregor Mendel

Who worked with pea plants Pisum sativum?

Gregor Mendel

If any offspring display the recessive phenotype, the mystery parent must be ________

Heterozygous

Monohybrid Cross

Only one trait is followed through a series of genetic crosses

P =

Parental generation

An important application of a _______ is to help us calculate the probability that a future child will have a particular genotype and phenotype.

Pedigree

Inheritance patterns of particular traits can be traced and described using what?

Pedigrees

What is the appearance of a particular trait called?

Phenotype

Most genes have multiple phenotypic effects, a property called _______

Pleiotropy

What is the P generation?

The first set of parents crossed

Over ______ genes have been linked to variation in height

400

If a recessive allele that causes a disease is rare, then the chance of two carriers meeting and mating is _____

Low

The Rh system is actually much more complicated than the ABO system because there are more than 30 combinations possible when inherited, however for general usage, the Rh ______ are grouped into two families - either positive or negative.

Proteins

_________ _______usually indicates polygenic inheritance

Quantitative variation

Dominant alleles that cause a lethal disease are _____ and arise by _______

Rare, mutation

To determine the genotype we can carry out a ______

Testcross

Probability

The likelihood that a particular event will happen. (flipping a coin)

Gene locus (plural loci)

The location for a specific gene on a specific type of chromosome

Cystic Fibrosis

The most common lethal genetic disease in the United States, striking one out of every 2,500 people of European descent

Homozygous Dominant

Both alleles for the same trait are dominant (AA)

Homozygous Recessive

Both alleles for the same trait are recessive (aa)

Testcross

Breeding the mystery individual with a homozygous recessive individual to determine the genotype

Quantitative characters

Characters of those that vary in the population along a continuum

What is used to compare observed ratios for a given cross compare with predicted ratios?

Chi-square analysis (χ2)

Carriers

Heterozygous individuals who carry the recessive allele but are phenotypically normal; most individuals with recessive disorders are born to carrier parents

Recessively inherited disorders show up only in individuals ________ for the allele

Homozygous

An individual with the dominant phenotype could be either _________ dominant or ________

Homozygous or heterozygous

Two purple flowered plants produce a white flowering offspring. This is an example of

Hybrid offspring

Can dominant alleles be masked by recessive alleles?

No

The ______ __ ______ is the phenotypic range of a genotype influenced by the environment

Norm of reaction

Complete dominance

Occurs when phenotypes of the heterozygote and dominant homozygote are identical

Heterozygous Dominant

One allele has the dominant form of the gene and the other has the recessive form (Aa)

Independent Assortment

One of Mendel's principles that states that genes for different traits can segregate independently during the formation of gametes

The RH factor determines the presence or absence of a protein on the surface of the RBC. If you carry this protein, you are Rh _________. If you don't carry the protein, you are Rh _______.

Positive, Negative

Many genetic disorders are inherited in a ________ manner. • These range from relatively mild to life threatening.

Recessive

This positive and negative blood type indicates the ____ factor

Rh

F2 =

Second generation of offspring (second filial)

About one out of ten African Americans has ______ ____ trait, an unusually high frequency of an allele with detrimental effects in homozygotes

Sickle cell

This disease affects one out of 400 African-Americans

Sickle-Cell Disease

In this disease: In homozygous individuals, all hemoglobin is abnormal. Symptoms include physical weakness, pain, organ damage, and even paralysis (pleiotropy)

Sickle-cell Disease

______ ________ and _________ in humans is an example of polygenic inheritance

Skin color and Height

Dominant allele

The allele that is fully expressed in the phenotype of a heterozygous individual

Recessive allele

The allele that is fully masked in the phenotype of a heterozygous individual

Genotype

The particular genes an organism carries (AA, Aa, aa)

Incomplete dominance

The phenotype of F1 hybrids is somewhere between the phenotypes of the two parental varieties

Sickle-cell Disease

This disease is caused by the substitution of a single amino acid in the hemoglobin protein in red blood cells

All offspring of a true breeding purple flowered pea plant will have purple flowers. This is an example of

True-Breeding Lineage

Most genes exist in populations in more than ____ allelic forms

Two

Codominance

Two dominant alleles affect the phenotype in separate, distinguishable ways

Dihybrid Cross

Two traits are followed through a series of genetic crosses

People with this type of blood group 0 Rh are called _________ donors

Universal

People with blood group AB Rh+ are called ________ _______

Universal Receivers

____ ear wax correlated with body odor (normal sweating) - affects sweat glands

Wet

Homozygous

When both alleles of the pair for a certain trait are identical

Hybrid Offspring

When offspring of a genetic cross inherit a pair of non-identical alleles for a trait

True-Breeding Lineage

When offspring of genetic crosses (breeding) that inherit two identical alleles for a trait. All offspring will have the same trait as their parents.

Heterozygous

When the two alleles of a pair for a certain trait are different