Bio T4 Chap 13

Card Set Information

Bio T4 Chap 13
2012-10-27 13:56:30

Show Answers:

  1. Genetics
    the scientific study of heredity and variation
  2. Heredity
    • the transmission of traits from one generation to the next
    • Offspring inherit genes, not traits

  3. Variation
    • by the differences in appearance that offspring show from parents and siblings
    • lead by sexual reproduction
  4. genes
    • units of heredity
    • Each gene = specific location on a chromosome ( a locus)
    • Version of a gene = an allele
  5. gametes
    • reproductive cells, the vehicles that transmit genes from one generation to the next
    • - contain haploid cells
  6. somatic cells
    • all cells of the body except the gametes and their precursors
    • contains 46 chromosomes in humans (23 pairs)
    • maternal set (from our mother) and a paternal set (from our father)
    • 1 chomosome contains several hundreds to thousands of genes in sequences of nucleotides
  7. locus
    gene’s specific location along the length of a chromosome
  8. asexual reproduction
    • a single individual is the sole parent and passes copies of all its genes to its offspring without the fusion of gametes.
    • give rises to a clone(a group of genetically identical individuals)
    • Ex: mitotic cell division
  9. sexual reproduction
    two parents give rise to offspring that have unique combinations of genes inherited from the two parents
  10. karyotype
    chromosomes are arranged in  pairs, starting with the longest chromosomes
  11. homologous chromosomes
    • pair of two chromosomes (represent by n)
    • Same length, same centromere position, carry versions of the same genes, govern the same traits
  12. sex chromosomes
    • the Xand Y chromosomes
    • Female has pair of (XX) Male has pair of (XY)
    • autosomes - other chromosomes
    • unfertilized egg =  X
    • sperm = X or Y
  13. diploid cell
    • cell with two chromosome sets (2n)
    • human = 46 (2n = 46)
  14. haploid cells
    • number of chromosomes (n).
    • For humans, the haploid number is 23 (n = 23)
    • consists of the 22 autosomes plus a single sex chromosome