Melanin

Genetics

The branch of biology studying heredity, genes, and genetic variation in organisms

Pedigree

A diagrammatic family tree using standardized symbols (squares for males, circles for females) to trace the inheritance of specific traits, diseases, or genotypes across generations

Punnett Squares

Possible alleles of 1 parent with the alleles of the 2nd parent, used to predict the genotypes and phenotypes of a cross between two organisms

Trait

A characteristic that is inherited

Alleles

Different versions of a gene

Dominant

A trait that is common in pedigree and found in every generation

Recessive

A trait that is rare in pedigree and often skips a generation

Phenotype

How a trait is expressed (how it looks)

Genotype

The two alleles an individual has for a trait (1 from each parent)

Homozygous

The two alleles are the same (AA or aa)

Heterozygous

The two alleles are different (Aa)

Autosomal

Regular inheritance

Sex-Linked Traits (X-Linked)

Genes on sex chromosomes (X or Y)

Karyotypes

Picture of all the chromosomes in a cell used for species identification, detecting nondisjunction and chromosomal mutations

XA Xa

Chromosomes for a female carrier

James Watson and Francis Crick (1953)

Who discovered DNA Structure?

DNA

Holds the instructions for making all the proteins in our bodies

Double Helix

Held together by hydrogen bonds created between specific Pairs of bases to form the connections between the 2 strands

Genes

Different sequences of nucleotides that code for proteins

Thymine (T)

Number of Adenine (A) always equals

Guanine (G)

Number of Cytosine (C) always equals

Transcription

DNA to mRNA

Translation

mRNA to amino acid chain

mRNA

Leaves the nucleus and travels to the ribosomes, in the cytoplasm

Amino Acid Chain

A linear polymer formed by amino acids linked together by peptide bonds, serving as the fundamental building block of proteins

Protein Synthesis

The biological process where cells generate new proteins, essential for structure, function, regulation of the body's tissues and organs, and also involves transcribing DNA into mRNA, followed by translating that message into chains of amino acids on ribosomes

Mutation

Any change in DNA

Substitution Mutation

Substitute one nucleotide for a different one (also known as Point Mutation)

Missense Mutation (type of Substitution mutation)

Different amino acid being made (Ex: UGU=CYS when the original is UAU=TYR)

Frameshift Mutation

Shifts the frame of reading codons by one of more nucleotides (Ex: a insertion or a deletion)

Silent mutation (type of substitution mutation)

Same amino acid being made

Nonsense mutation (Type of substitution mutation)

Amino acid changed into a STOP codon (protein might not be made or could function differently due to compromised structure)

Insertion Mutation

one type of frameshift mutation

Deletion mutation

type of frameshift mutation