Wednesday, March 25, 2009
Wednes-Day 1
AP Chem- did another selective precipitation problem; this time, we added a cation, Ag+, in order to selectively precipitate either the chloride or the phosphate ion from solution.
We then did the typical calculations:
-which anion precipitates first
-what is the concentration of the precipitating ion JUST as the other ion is about to precipitate
-was there "complete" precipitation of the less soluble salt's anion at this point
We then discussed how and why certain salts (and hydroxide bases) are made more soluble in acidic solutions. For ANY salt that has anions that are strong enough to react with H+, i.e. ALL SALTS EXCEPT for chlorides, bromides, iodides, nitrates, and perchlorates, the loss of the anions will cause a Le Chatelier shift that results in more dissolving of the salt.
We introduced Thermodynamics, which we will complete next week.
Bio 6/7- Mendel's main observations are summarized in the Law of Dominance, the Law of Segregation and Recombination, and the Law of Independent Assortment.
We saw that the genes for certain traits can come in two or more forms/alleles. From Mendel's experiments, he saw that typically one allele DOMINATES (shows up in offsprings' phenotype) over the other (recessive) allele. He also showed, based on the percentage of offspring with a specific phenotype, that the alleles (within a given parent) segregate/separate as the sex cells are made; we now know that this occurs during anaphase II of meiosis as the chromatids, each carrying one allele per gene) are pulled apart and go to separate sex cells.
Alleles are then "recombined" when the diploid number of chromosomes is restored via fertilization of an ovum by a sperm to form a zygote.
We discussed the difference between GENOTYPE and PHENOTYPE. Genotype refers LITERALLY to the specific alleles that an individual has for a given trait.
For genes that have only two alleles, one dominant and one recessive, there are THREE possible GENOTYPES:
HOMOZYGOUS DOMINANT, e.g. TT
HETEROZYGOUS, e.g. Tt or tT (hetero means different; this type has two DIFFERENT alleles)
HOMOZYGOUS RECESSIVE, e.g. tt
A PHenotype is what you PHysically SEE expressed by the organism! In order to have the recessive alleles appear physically (expressed physically), an organism MUST have the homozygous RECESSIVE GENOTYPE, otherwise, BY DEFINITION, the dominant allele will be expressed in the phenotype INSTEAD of the recessive allele.
Therefore, a Tt or a TT GENOTYPE will be expressed as the "TALL" PHENOTYPE (you can SEE the tall characteristics even though you can't physically see the genes that cause the phenotype). However, a "tt" genotype will form/be expressed as the "SHORT" PHENOTYPE.
We discussed and showed, using Punnett squares, the cause of the genotype and phenotype ratios that are expected in the F1 and F2 generations for alleles that exhibit a dominant/recessive relationship. We also introduced the two types of intermediate dominance: codominance (both alleles separately are expressed) and incomplete dominance (an average blend of the two parent phenotypes is seen).
We then finished up questions from the past two labs. These writeups are due on Monday so that I can enter your lab grades.
Bio 8- His main observations are summarized in the Law of Dominance, the Law of Segregation and Recombination, and the Law of Independent Assortment.
We saw that the genes for certain traits can come in two or more forms/alleles. From Mendel's experiments, he saw that typically one allele DOMINATES (shows up in offsprings' phenotype) over the other (recessive) allele. He also showed, based on the percentage of offspring with a specific phenotype, that the alleles (within a given parent) segregate/separate as the sex cells are made; we now know that this occurs during anaphase II of meiosis as the chromatids, each carrying one allele per gene) are pulled apart and go to separate sex cells.
Alleles are then "recombined" when the diploid number of chromosomes is restored via fertilization of an ovum by a sperm to form a zygote.
We discussed the difference between GENOTYPE and PHENOTYPE. Genotype refers LITERALLY to the specific alleles that an individual has for a given trait.
For genes that have only two alleles, one dominant and one recessive, there are THREE possible GENOTYPES:
HOMOZYGOUS DOMINANT, e.g. TT
HETEROZYGOUS, e.g. Tt or tT (hetero means different; this type has two DIFFERENT alleles)
HOMOZYGOUS RECESSIVE, e.g. tt
A PHenotype is what you PHysically SEE expressed by the organism! In order to have the recessive alleles appear physically (expressed physically), an organism MUST have the homozygous RECESSIVE GENOTYPE, otherwise, BY DEFINITION, the dominant allele will be expressed in the phenotype INSTEAD of the recessive allele.
Therefore, a Tt or a TT GENOTYPE will be expressed as the "TALL" PHENOTYPE (you can SEE the tall characteristics even though you can't physically see the genes that cause the phenotype). However, a "tt" genotype will form/be expressed as the "SHORT" PHENOTYPE.
We discussed and showed, using Punnett squares, the cause of the genotype and phenotype ratios that are expected in the F1 and F2 generations for alleles that exhibit a dominant/recessive relationship.
We then did the typical calculations:
-which anion precipitates first
-what is the concentration of the precipitating ion JUST as the other ion is about to precipitate
-was there "complete" precipitation of the less soluble salt's anion at this point
We then discussed how and why certain salts (and hydroxide bases) are made more soluble in acidic solutions. For ANY salt that has anions that are strong enough to react with H+, i.e. ALL SALTS EXCEPT for chlorides, bromides, iodides, nitrates, and perchlorates, the loss of the anions will cause a Le Chatelier shift that results in more dissolving of the salt.
We introduced Thermodynamics, which we will complete next week.
Bio 6/7- Mendel's main observations are summarized in the Law of Dominance, the Law of Segregation and Recombination, and the Law of Independent Assortment.
We saw that the genes for certain traits can come in two or more forms/alleles. From Mendel's experiments, he saw that typically one allele DOMINATES (shows up in offsprings' phenotype) over the other (recessive) allele. He also showed, based on the percentage of offspring with a specific phenotype, that the alleles (within a given parent) segregate/separate as the sex cells are made; we now know that this occurs during anaphase II of meiosis as the chromatids, each carrying one allele per gene) are pulled apart and go to separate sex cells.
Alleles are then "recombined" when the diploid number of chromosomes is restored via fertilization of an ovum by a sperm to form a zygote.
We discussed the difference between GENOTYPE and PHENOTYPE. Genotype refers LITERALLY to the specific alleles that an individual has for a given trait.
For genes that have only two alleles, one dominant and one recessive, there are THREE possible GENOTYPES:
HOMOZYGOUS DOMINANT, e.g. TT
HETEROZYGOUS, e.g. Tt or tT (hetero means different; this type has two DIFFERENT alleles)
HOMOZYGOUS RECESSIVE, e.g. tt
A PHenotype is what you PHysically SEE expressed by the organism! In order to have the recessive alleles appear physically (expressed physically), an organism MUST have the homozygous RECESSIVE GENOTYPE, otherwise, BY DEFINITION, the dominant allele will be expressed in the phenotype INSTEAD of the recessive allele.
Therefore, a Tt or a TT GENOTYPE will be expressed as the "TALL" PHENOTYPE (you can SEE the tall characteristics even though you can't physically see the genes that cause the phenotype). However, a "tt" genotype will form/be expressed as the "SHORT" PHENOTYPE.
We discussed and showed, using Punnett squares, the cause of the genotype and phenotype ratios that are expected in the F1 and F2 generations for alleles that exhibit a dominant/recessive relationship. We also introduced the two types of intermediate dominance: codominance (both alleles separately are expressed) and incomplete dominance (an average blend of the two parent phenotypes is seen).
We then finished up questions from the past two labs. These writeups are due on Monday so that I can enter your lab grades.
Bio 8- His main observations are summarized in the Law of Dominance, the Law of Segregation and Recombination, and the Law of Independent Assortment.
We saw that the genes for certain traits can come in two or more forms/alleles. From Mendel's experiments, he saw that typically one allele DOMINATES (shows up in offsprings' phenotype) over the other (recessive) allele. He also showed, based on the percentage of offspring with a specific phenotype, that the alleles (within a given parent) segregate/separate as the sex cells are made; we now know that this occurs during anaphase II of meiosis as the chromatids, each carrying one allele per gene) are pulled apart and go to separate sex cells.
Alleles are then "recombined" when the diploid number of chromosomes is restored via fertilization of an ovum by a sperm to form a zygote.
We discussed the difference between GENOTYPE and PHENOTYPE. Genotype refers LITERALLY to the specific alleles that an individual has for a given trait.
For genes that have only two alleles, one dominant and one recessive, there are THREE possible GENOTYPES:
HOMOZYGOUS DOMINANT, e.g. TT
HETEROZYGOUS, e.g. Tt or tT (hetero means different; this type has two DIFFERENT alleles)
HOMOZYGOUS RECESSIVE, e.g. tt
A PHenotype is what you PHysically SEE expressed by the organism! In order to have the recessive alleles appear physically (expressed physically), an organism MUST have the homozygous RECESSIVE GENOTYPE, otherwise, BY DEFINITION, the dominant allele will be expressed in the phenotype INSTEAD of the recessive allele.
Therefore, a Tt or a TT GENOTYPE will be expressed as the "TALL" PHENOTYPE (you can SEE the tall characteristics even though you can't physically see the genes that cause the phenotype). However, a "tt" genotype will form/be expressed as the "SHORT" PHENOTYPE.
We discussed and showed, using Punnett squares, the cause of the genotype and phenotype ratios that are expected in the F1 and F2 generations for alleles that exhibit a dominant/recessive relationship.
# posted by C @ 11:04 PM 
