Melanin biology

Autosomal chromosomes

First 22 pairs are autosomal in humans, so not impact the sex of an organism

Sex chromosomes

23rd pair, impact the sex of an organism

Genotype

The actual genes (alleles) “Aa”

Phenotype

The traits that an organism has (height)

Homozygous

Pair of genes that are the same gene (AA or aa)

Heterozygous

Genes that are not the same gene (Aa)

Homozygous dominant

AA

Homozygous recessive

aa

If a trait is Autosomal dominant

it is found on one of non-sex chromosomes and is expressed anytime dominant gene is present

If a trait Autosomal recessive

Found on one of non-sex chromosomes and is expressed anytime TWO recessive genes are present

If a trait is sex linked

Found on the X or Y chromosome (sex chromosome)

Male sex chromosome

XY

Female sex chromosome

XX

Sex linked disease the trait is normally expressed in

Males, (XY, Y cannot combat X)

Majority of sex linked traits are found on the

X chromosome

Combat sex linked trait because of their other X chromosome

Females

Carrier

Female; carry the normal version of the gene on one of their X chromosomes,a en affected gene on their other

Diploid (2n)

2 sets of chromosomes, one from mom and one from dad. Body cells like skin, hair, check, and muscles. Every cell in the body is diploid, except for sperm and the egg. Zygote

Haploid (n)

Half the amount of chromosomes, has a single set of chromosomes. Sperm and egg are haploid

Gamete

Sex cells (haploid)

Karyotype

Visual representation of all of the chromosomes in a cell

Genetics

Study of heredity

Heredity

The passing of traits from parent to offspring

Cross

Breeding of two individual organisms

Trait

Specific characteristics such as seed color or plant height

Genes

Traits are determined by chemical factors called genes

Alleles

Different forms of genes

Hybrids

Heterozygous (carriers of Aa) offspring of crosses between parents with different traits

First Filial Generation or F1:

offspring from first parental cross

Second Filial Generation or F2

Offspring in second generation produced by crossing F1’s

Zygote

The fusion of a sperm and egg to form a zygote, a zygote is a fertilized egg

Homologous pairs (tetrads)

Pairs of chromosomes (maternal and paternal) that are similar in shape and size. Cary genes controlling the same inherited traits, each locus (position of a gene) is in the same position on homologues, humans have 23 pairs of homologous chromosomes. 22 pairs of autosomes and 1 pair of sex chromosomes

Homologous pair has 4 chromatids

Called a tetrad

23 sets of Homologous chromosomes

Each homologous set is made of 2 homologues

Autosomes

Code for most of the offsprings traits, the autosomes are sets 1-22

Sex chromosomes

Are the 23rd set