Patterns of Inheritance - FINAL TERM BIOLOGY

Codominance

When two dominant alleles are present, both alleles will be expressed when combined.

Codominance

Absence of a recessive allele.

Roan

Red and white hairs are expressed equally.

Codominance

Inheritance of the MN blood antigen (a glycoprotein found on the surface of red blood cells in humans) involves _____.

Codominance

Two traits come out.

Capitalized

Letters used for the punnett square in codominance should be _____, since only two dominant alleles are present.

Incomplete dominance

When dominant alleles are absent, only a recessive allele will combine with another recessive allele.

Incomplete dominance

"The pattern of inheritance, where an intermediate phenotype other than the two parental phenotypes, is observed."

Incomplete dominance

The offspring does not resemble either of the parents.

Incomplete dominance

Absence of a dominant allele.

Incomplete dominance

Two traits are blended.

Lowercase and use a superscript

Letters used for the punnett square in incomplete dominance should be in _____ and use a _____, since only two recessive alleles are present.

Multiple alleles

When more than two alleles exist in a certain character.

Antigen

Substances that can trigger immune responses if foreign to body (e.g., A, B, O, AB).

O

Universal donor blood type that can only receive blood from its own blood type. Carry only the __ genotype.

AB

Universal receiver blood type that can only donate blood to its own blood type. Carry only the __ genotype.

Rhesus (Rh) factor

An inherited protein found on the surface of red blood cells. If your blood has the protein, you're Rh positive. If your blood lacks the protein, you're Rh negative.

Rh positive

The most common blood type.

+

The symbol indicating the presence of the protein Rh factor found in blood types (e.g., A+, B+, AB+, O+).

-

The symbol indicating the lack of the protein Rh factor found in blood types (e.g., A-, B-, AB-, O-).

Multiple alleles

Inheritance of ABO blood types in humans involves _____.

Agglutinogens

Also known as A and B antigens. Found on the surface of RBCs in humans and are used as the most common means of blood typing.

Agglutinin (Antibodies)

The presence of agglutinogens causes the formation of _____, a substance that makes particles coagulate.

Lethal genes

A condition when a certain combination of alleles will result to death of the carrier.

Albinism

Absence of chlorophyll in green plants will lead to _____, which is lethal to the carrier because of the inability to undergo photosynthesis.

Polygenic inheritance

Traits that are controlled by two or more genes (e.g., in humans: skin color, height, intelligence quotient, eye color).

Polygenes

Genes involved in polygenic inheritance, often found in different chromosomes.

Sex-linked Inheritance

Inheritance of genes located in the sex chromosomes.

X chromosome

A submetacentric chromosome having an arm shorter than the other, with roughy 156 million base pairs of DNA containing approximately 800 protein-coding genes.

Y chromosome

A relatively smaller telocentric chromosome with about 57 million base pairs of DNA containing approximately 63 protein-coding genes.

XX chromosome

Female.

XY chromosome

Male.

Color blindness

An inherited sex-linked disease in humans characterized by decreased ability to see color differences.

Color blindness

This is caused by a mutation in genes that produce red and green light-sensitive proteins in the X chromosome.

Recessive X-linked gene

Color blindness is inherited as a _____ gene, thus, it affects males more frequently than females.

Ishihara test

A common color perception test to determine color blindness in a person.

Ishihara test

The test consists of pseudoisochromatic plates (PIP) that contains dots that appear random sizes and colors.

Dr. Shinobu Ishihara

Developed the Ishihara Test in 1917 at the University of Tokyo.

Hemophilia A

A genetic disorder caused by missing or defective factor VIII, a clotting protein. Although it is passed down from parents to children, about 1/3 of cases are caused by a spontaneous mutation, a change in a gene.

Factor VIII (FVIII) deficiency or classic hemophilia

State the other terms for Hemophilia A:

Carrier

A female parent who possesses one X-linked recessive mutation is considered a _____. They will not manifest clinical symptoms of the disorder but will pass on the trait to the next generation.

Sex-influenced Inheritance

Refers to autosomal traits whose expression of dominance is affected by the sex of the individual. Follows the Mendelian pattern of dominance and recessiveness. However, the effect in one sex is dominant whereas it is recessive in another sex.

Autosomal

A specific gene is not on a sex chromosome (X and Y) and is a numbered chromosome (pairs 1-22).

Male-pattern baldness

The expression of baldness is influenced by the testosterone,which explains the higher frequency of baldness in males compared to females

Males; Females

Hairlip and Gout is more dominant in _____ than _____.

Females; Males

Spina bifida is more dominant in _____ than _____.

Hairlip

Cleft lip.

Gout

A type of arthritis.

Spina bifida

Congenital defect of the spine in which part of the spinal cord and its meninges are exposed.

Pleiotropy

A condition when one gene causes several effects (multiple traits) in various organs of the body.

Pleiotropy

Will then result to syndrome, which is a group of symptoms that may appear simultaneously, an indication of a particular genetic mutation.

Marfan syndrome; Porphyria; Phenylketonuria; Albinism; Autism; Schizophrenia

Enumerate six (6) examples of Pleiotropy:

MPPAAS

Sickle cell anemia

Mutations in the beta-globin gene (HBB gene) in chromosome 11 will manifest to _____.

Pedigree analysis

Symbols are used to represent members and relationships in a family being analyzed.

Normal male

Unshaded square.

Afflicted male

Shaded square.

Normal female

Unshaded circle.

Afflicted female

Shaded circle.

Unknown sex

Unshaded diamond.

Heterozygote

Fraternal twins

Identical twins

Marriage (related)

Generation no.

I, II, III

Offspring no.

1,2,3