Flashcards
Biology Level 1 NCEA
Cards in this deck (21)
- 1AlleleIs the expression of a gene (e.g. either blue or brown allele for the eye colour gene)
- 2Dominant AlleleIs the one that is always expressed (If its present). The recessive allele will only be expressed if there are NO dominant alleles present,
- 3GenotypeIs the genetic code an organism has for a particular trait. (e.g. TT, Tt, tt)
- 4PhenotypeIs the physical appearance of that genotype (e.g. brown eyes, blue eyes etc.)
- 5HomozygousIs when two alleles are the same (e.g. TT or tt)
- 6HeterozygousIs when two alleles are different (e.g. Tt)
- 7DNAIs the genetic code in the nucleus. Made up of bases; A, C, G and T. Is a double helix structed
- 8ChromosomeA strand of coiled DNA.
- 9GeneA section of DNA that codes for a trait.
- 10TraitA characteristic or feature.
- 11Mitosis1. DNA replicates
2. Chromosomes line up
3. Chromatids pulled apart
4. Nuclear membranes form
5. Two cells form.
Two identical daughter cells are produced for growth and repair in the body cells. - 12Semi ConservativeHalf the daughter strand is old from the parent strand and half of the strand is new from the new base pairs.
- 13MeiosisChromosome cross over. Only occurs in the sex cells and produces four different daughter cells.
- 14GametesAre sex cells, they have half the number of chromosomes.
- 15ZygoteTwo gametes make a zygote, which has a full number of chromosomes.
- 16Pure BreedingIs when both parents are homozygous.
- 17Genetic VariationAllows a species to adapt to its changing environment.Can come from
1. Meiosis
2. Crossing over
3. Mutations - 18Punnet SquareShows the potential offspring
- 19Genotype ratioThe ratio of offspring with different alleles
- 20Phenotype ratioThe ratio of offspring with different physical traits.
- 21Pedigree ChartShows the phenotype of a family