level 1 NCEA genetics

genotype

combination of alleles for any given trait

Phenotype

Physical expression of the genotype

DNA

molecule with a double helix shape, made of nucleotide bases that carries the code for a trait/characteristic/proteins

Chromosome

a strand of DNA that contains many genes

Crossing Over:

Chromosomes pair up and swap sections of their DNA, creating new combinations of alleles.

Independent Assortment:

Chromosomes line up randomly in the middle of the cell before dividing, resulting in a random mix of maternal and paternal chromosomes in the gametes.

Segregation:

The paired chromosomes are separated, ensuring each resulting gamete gets only one copy of each chromosome pair.

Immigration

brings new individuals into a population, increasing the size of the population and potentially altering the allele frequency

Emigration

removes individuals from a population, decreasing the size of the population and potentially altering the allele frequency

Mutation

random, spontaneous change in the in the base sequence of a gene

Population

a group of organisms of the same species living in the same area at the same time that can (potentially) interbreed and produce fertile offspring

Genetic markers

DNA sequences with a known physical location on a chromosome helped to identify individuals, track inheritance of genes, or study genetic variations within and between populations.

fertilisation

Random male and female gametes join, each with unique DNA, producing a genetically unique zygote / offspring.

sexual reproduction

Random fertilisation produce new combination of alleles and thus genetic variation between individuals.

Carrier

A heterozygous individual who carries a single copy of a recessive allele for a trait without displaying that phenotype.

DNA sequencing

The laboratory method used to determine the exact order of the four nucleotide bases within a strand of genetic material.