genetics

Cards (30)

  • gene - a sequence of bases on a DNA molecule that codes for a protein which results in a characteristic
  • allele - an alternative version of a gene that is found at the same position on a chromosome
  • genotype - genetic constitution of an organism
  • phenotype -  expression of this genetic constitution and its interaction with the environment
  • dominant - alleles whose characteristics appear in the phenotype
  • recessive - allele where it only appears on the phenotype if two copies are present
  • co-dominant - alleles that are both expressed in the phenotype
  • locus - the fixed position of a gene on a chromosome
  • homozygote - an organism that carries two copies of the same allele
  • heterozygus - an organism that carries two different alleles
  • carrier - a person carrying an allele which is not expressed on the phenotype but can be passed onto the offspring
  • diploid organism - the alleles at a specific locus may be either homozygous or heterozygous.
  • diploid - two sets of chromosomes and so we also have two alleles for each gene
  • gamete - contain only one allele for each gene
  • genetic diagrams - can be used to predict the genotypes and phenotypes of offspring
  • monohybrid inheritance - inheritance of a characteristic controlled by a single gene. show the likelihood of different alleles of that gene being inherited
  • dihybrid crosses - how two different genes are inherited at the same time
  • add the labels
    A) dihybrid
    B) 3
    C) 9
    D) 3
    E) 1
    F) heterozygous
    G) heterozygous
    H) heterozygous
    I) 2
  • autosome - any chromosome that is not a sex chromosome
  • autosomal genes - genes that are found on autosomes (non-sex chromosomes)
  • genes on the same autosome are linked because they will stay together during independent segregation of chromosomes in meiosis I and their alleles will be passed onto their offspring together. the only way this wont happen is if crossing over takes place and splits them up
  • the closer the genes on autosome the more closely they are linked this is because crossing over is less likely to split them up
  • if two genes are autosomally linked you will not get the phenothypic ratio you would expect
  • episatis - when one gene affects the expression of the other gene by blocking it
  • the chi-squared test - is a statistical test used to see if the results of an experiment support the expected results
  • the chi-squared test can tell us if we can reject the null hypothesis
  • null hypothesis - there is no significant difference between the expected data and observed data
  • if the null hypothesis is rejected then it means that there is a significant difference between the expected and observed data so accept the alternative hypothesis
  • chi-squared can be used to com-pare the goodness of fit of observed phenotypic ratios with the expected ratios
  • labels
    A) E
    B) o
    C) 2
    D) observed
    E) expected
    F) degrees of freedom
    G) classes - 1
    H) 0.05
    I) there is
    J) rejected
    K) rejected
    L) observed and expected