Biology - Melanin Unit

Pedigree

A chart showing the inheritance of traits through generations.

Alleles

Different versions of the same gene.

Mutation

A change in the DNA sequence.

Genotype

The genetic makeup of an organism.

Phenotype

The physical appearance of a trait.

Homozygous

Having two identical alleles for a gene.

Heterozygous

Having two different alleles for a gene.

Genes

DNA segments that code for traits.

Evolution

Change in a species over time due to genetic variations.

Natural Selection

Survival of organisms with traits best suited to their environment.

Codominance

When both alleles are expressed equally.

Incomplete Dominance

When alleles blend to produce a new trait.

Multiple Alleles

A gene with more than two allele options.

Sex-Linked Traits

Traits carried on sex chromosomes (X or Y).

Hemophilia

A condition where blood doesn't clot properly.

Melanin

Pigment responsible for skin, hair, and eye color.

Pigmentation

The coloration of tissues.

Melanocytes

Skin cells that produce melanin.

UV Radiation

Ultraviolet rays from the sun.

Adaptation

A change helping an organism survive.

Biodiversity

Variety of life in an environment.

Overpopulation

More organisms than resources can support.

Competition

Struggle for survival due to limited resources.

Central Dogma

Flow of genetic information: DNA → RNA → Protein.

Transcription

Process of making RNA from DNA.

Translation

Making proteins from RNA.

Ribosome

Cell structure where proteins are made.

Point Mutation

A single nucleotide change.

Frameshift Mutation

Adding/removing a nucleotide shifts the reading frame.

Variation

Any difference between individuals of the same species.

relative fitness

individual's ability to survive and reproduce relative to the rest of the population

Adaptation

A trait that helps an organism survive and reproduce

RNA

A single-stranded nucleic acid that passes along genetic messages

tRNA (transfer RNA)

The molecule that carries the amino-acid to the Ribosome. It also has the Anti-Codon.

Codon

A sequence of three nucleotides on a strand of messenger RNA

Anticodon

group of three bases on a tRNA molecule that are complementary to an mRNA codon

protein synthesis

Forming proteins based on information in DNA and carried out by RNA

Silent Mutation

A mutation that changes a single nucleotide, but does not change the amino acid created.

Missense

a mutation that changes one amino acid

nonsense mutation

A mutation that changes an amino acid codon to one of the three stop codons, resulting in a shorter and usually nonfunctional protein.

Frameshift insertion

a single base is added

Frameshift deletion

a mutation in which a nucleotide is deleted shifting amino acid arrangement