exam 4 bio notes

exam 4 bio notes - 20:36 MendelianGenetics Questions

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
20:36 Mendelian Genetics Questions A cell in G1 of the cell cycle has 12 chromosomes in homologous pairs. It  undergoes Meiosis, during Metaphase II each cell would contain 6 chromosomes  with no pairs.  If the first division of meiosis results in haploid cells why do the second division? Crossing over and the production of non-identical sister chromosomes Two purple flowered pea plants are crossed and the offspring include both purple  and white flowered plants. What are the genotypes of the parents LIFE CYCLES (13.6) Alternation of Generations Organisms with multi cellular haploid stages INHERITANCE Reproduction: What is the outcome of asexual? Identical offspring (mitosis) What is the outcome of sexual? Different offspring (meiosis)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Key point: What is the role of the parent? Produce gametes What type of cell division produces gametes? Meiosis GENETIC DEFINITIONS Gene : information (DNA sequence) leading to a particular characteristic Allele : one form of a gene Locus : the location of a gene on a chromosome  Phenotype : the physical expression of the alleles (purple flowers) Genotype : a listing of the alleles that an individual has. Often given for just one or  two genes. Homozygous : the condition in which both alleles for a gene are the same. Heterozygous : the condition in which the alleles for a gene are different.  Gamete Formation Rules An allele can be present in a gamete only if that individual has that allele.  For every pairs of alleles an individual only gets one.  Monohybrid Cross (flower color)
Background image of page 2
Created by Mendel (14.3) True Breeding Parental  P Purple x White 1 st  Filial  F1 all purple  2 nd  Filial  F2 ¾ purple, ¼ white P phenotype  Purple x White    Genotype P/P         p/p    Gametes P      p F1 genotype P/p      Phenotype     all purple      Gametes                P or p         P or p Ratios of Offspring Genotypic Ratio: 1 P/P: 2 P/P: 1 p/p  Phenotypic Ratio:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3 purple flowered:1 white flowered Mendel’s Observations One trait disappeared in the F1s The recessive trait reappeared in the F2 generations and always in a 3:1 ratio Mendel’s Explanation Heredity is determined by discrete factors These: Occur in pairs, except in gametes where there is only one for each pair. TEST CROSS (14.6)
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/07/2010 for the course BIOL 1201 taught by Professor Wishtichusen during the Fall '07 term at LSU.

Page1 / 13

exam 4 bio notes - 20:36 MendelianGenetics Questions

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online