Mendelian Genetics 13 and Chromosomal Inheritance 14

Vocabulary flashcards covering key definitions and foundational concepts from lectures on Mendelian Genetics and Chromosomes and Inheritance.

Dominant

The 'stronger' version of a gene that will show up if an individual has just one copy of it.

Recessive

A form of a gene that only shows up if two copies of it are present and there is no dominant version.

Allele

Any of the possible forms that a hereditary characteristic can take.

Trait

Any characteristic that can be inherited, such as flower color.

Homozygous

The condition where the two alleles that an individual receives for a particular characteristic are the same.

Heterozygous

The condition where the two alleles for a particular characteristic are different (such as $Pp$).

Genotype

A description of the alleles for a particular trait.

ex. inheriting one brown eye gene and one blue eye gene

Phenotype

A description of the physical effect of the two alleles.

Incomplete Dominance

A pattern of inheritance where the phenotype for a heterozygous individual is somewhere between the two homozygous phenotypes (a blend).

Codominance

A pattern of inheritance where two alleles can be expressed pretty much equally.

Multiple Alleles

A situation where there are more than two possible alleles for a gene, such as the three alleles (A, B, and O) in human blood types.

Polygenic Inheritance

An inheritance pattern where traits are affected by more than one gene, such as height and skin color in humans.

Pleiotropy

A phenomenon where a single gene can have more than one effect (trait or characteristic). like sickle cell anemia

Sex-Linked Gene

A gene located on a sex chromosome, most commonly on the X chromosome, but also including genes located only on the Y chromosome.

Aneuploidy

The condition in which a zygote has the wrong number of chromosomes.

Non-disjunction

A genetic error where sister chromatids fail to separate properly during meiosis.

Translocation

A chromosome structure change where a chromosomal segment is moved to another chromosome.

where does Mitochondrial DNA come from (which parent)?

Extranuclear genes that are inherited strictly from the mother because they are carried only in the eggs.

what do most Mitochondrial Genes affect?

Genes affect energy transformation (cellular respiration and energy production), problems with which show up first in high-energy body parts such as muscles and nerves.

in humans why is it that the father determines the sex of a child?

All children will get an X chromosome from their mother, but they could only get an X or a Y chromosome from their father.

list four ways that chromosomes struxture changes can lead to mutation

1. Deletion

2. Duplication

3. Inversion

4. Translocation