HB+Human+Genetics

=__Human Genetics__=


 * Genotype:**
 * specific alleles (2) for a particular gene written with symbols //EE or Ee or ee//
 * Alleles:**
 * alternate forms of a specific gene at the same position (locus) of a gene (allele for unattached earlobes and attached lobes); alleles usually occur in pairs //E or e//
 * Dominant allele:**
 * will be expressed and will mask a recessive gene (Ee--unattached ears is dominant)
 * Recessive allele:**
 * allele that is only expressed when a gene has two of this type of allele (ee)
 * Locus:**
 * the location of the gene on the chromosome
 * Homozygous dominant:**
 * genotype: 2 dominant alleles (EE)
 * Phenotype:**
 * physical characteristics (attached earlobes)
 * Homozygous recessive:**
 * genotype 2 recessive alleles (ee)
 * heterozygous**:
 * genotype of one dominant allele and one recessive allele (Ee)

What is the difference between genotype and phenotype?

 * Phenotype is the physical characteristic of a person, which comes from a genotype.

What are the three possible genotypes and two possible phenotypes for a characteristic that is controlled by two alleles, one being dominant and the other recessive?

 * EE, Ee, ee
 * dominant phenotype due to EE or Ee
 * recessive phenotype due to ee

For each of the following genotypes, give all the possible gametes.

 * WW- W
 * WWSs- WS, Ws
 * Tt- T, t
 * Ttgg- Tg, tg
 * AaBb- Ab, AB, aB, ab

For each of the following, state whether a genotype or a gamete is represented.

 * D- gamete
 * Ll- genotype
 * Pw- gamete
 * LlGg- genotype

What is the genotype of the individual from the following crosses?

 * ES x es = EeSs
 * eS x es = eeSs


 * Monohybrid**:
 * a cross for one trait (one gene) like Tt x Tt or TT x tt
 * Punnett square**:
 * a chart that lists every possible combination of the mother and father's sperm and egg combinations

A man with a widow's peak has a mother with a a straight hairline. Widow's peak (W) is dominant over straight hairline (w). What is the genotype of the man?

 * Ww

Both a man and a woman are heterozygous for freckles. Freckles (F) are dominant over no freckles (f). What is the chance that their child will have freckles?
===Both you and your sister or brother have attached earlobes, yet your parents have unattached earlobes. Unattached earlobes (E) are dominant over attached earlobes (e) What are the genotypes of your parents?===
 * 75%
 * Both are Ee