Quiz 4: Human Genetics
Each member of a class sampled a piece of PTC testing paper. Thirty people sampled the chemical. Twenty persons were tasters. How many had heterozygous genes?
0-20
Each member of a class sampled a piece of PTC testing paper. Thirty people sampled the chemical. Twenty persons were tasters. How many had homozygous recessive genes?
10
Each member of a class sampled a piece of PTC testing paper. Thirty people sampled the chemical. Twenty persons were tasters. How many had homozygous genes?
10-30
What genotype produces a tenor voice?
AA
A condition caused by the presence of an extra chromosome 21
Down's Syndrome
A family pedigree is a chart of various patterns that shows a general trend.
False
In sex-linked inheritance, females are most susceptible because they have only one X chromosome. Therefore, whichever gene is present, be it dominant or recessive, it is expressed. The male has two X chromosomes, and in order to be expressed, both genes must be recessive.
False
A pedigree is not helpful to a counselor in predicting the probability of a recessive gene being present and the chances for an offspring to receive the gene and express the trait.
False.
(XXY) An abnormality affecting males where there is an extra X chromosome
Klinefelter's Syndrome
An inherited protein found on the surface of the red blood cell membrane
Rh factor
Is straight or curly hair dominant?
Straight
(XO) An abnormality where one of the sex chromosomes is missing leaving a total of 45
Turner's Syndrome
What would be a female bleeder's genotype? (Let X B stand for the normal condition for clotting and X b stand for the recessive hemophilia allele.)
XbXb
What are three genotypes that parents must have in order for a daughter to have XbXb?
XbXb, XbY, and XBXb
Which parental combination could result in a child with XbXb?
XbY and XXb
What genotypes express hemophilia?
XbY, XbXb
Why would it be wise for a woman carrying the hemophilia gene to keep her son from being circumcised?
because the probability of hemophilia would be 50%
The blood type AB is an example of _____________ dominance.
co
Both members of an allelic pair contribute equally to the phenotype
codominance
Are dark or light eyes dominant?
dark
Is dark or light hair dominant?
dark hair
Is a bent pinky dominant or recessive?
dominant.
Is mid digital hair dominant or recessive?
dominant.
The factors that are responsible for the ABO blood type, or the Rh, are located on the surface of the
erythrocyte
Are freckles or no freckles dominant?
freckles
Are free or fused earlobes dominant?
free
How common the gene is in the population
gene frequency
All of the genes present in a specific population
gene pool
A hereditary condition for bleeding due to the inability to clot properly
hemophilia
A gene located on the Y chromosome in XY species
holandric gene
What sex-linked diseases are mentioned in the lesson?
night blindness, rolling eyeballs, dysfunctional sweat glands, white forelock, muscular dystrophy, certain deafness, color blindness, and diabetes.
The ancestral history of an individual; a chart showing the history of a trait in the family
pedigree
The study of a hereditary trait in a large population
population genetics
What are some of the results of having sickle-cell anemia?
resistance to malaria, reduced oxygen respiration, and reduced viability.
Is right or left handedness dominant?
right
A hereditary form of anemia
sickle cell anemia
What is true about the heterozygous sickle-cell (HbA HbS) condition?
sickle-cell anemia is expressed under conditions of oxygen deficiency.
In conditions of low oxygen some cells sickle
sickle-cell trait
Is flaky or wet earwax dominant?
wet
In a large population, approximately 65 percent are tasters and 35 percent are nontasters. Does the class compare favorably to the general population?
yes
The Talmud permitted a father with hemophilia to have his son circumcised. Would this preclude all possible problems?
yes-if the mother is not a possible carrier
