Expert: Walter Hintz - 7/8/2006

Question
1.The type of inheritance shown when a red- flowering plant is crossed with a white- flowering plant and only pink- flowering plants are produced is __________. (1 point)
inbreeding
incomplete dominance
polygenic inheritance =my answer
codominance




2.Which series is arranged in order from largest to smallest in size? (1 point)
chromosome, nucleus, cell, DNA, nucleotide
cell, nucleus, chromosome, DNA, nucleotide =myanswer
nucleotide, chromosome, cell, DNA, nucleus
cell, nucleotide, nucleus, DNA, chromosome




3.A human genetic defect that results in the failure to metabolize the amino acid phenylalanine is _________. (1 point)
Turner Syndrome
Down Syndrome
PKU
Cystic Fibrosis =my answer




4.Messanger RNA is formed in the process of ________. (1 point)
transcription =my answer
translation
replication
mutation




5.Which of the following nucleotide pair bonds would be found in a DNA molecule? (1 point)
adenine- guanine
guanine- cytosine
adenine- cytosine
cytosine- uracil =my answer




6.If a female fruit fly heterozygous for red eyes (XRXr) crossed with a white eyed male (XrY), what percent of their offspring would have white eyes. (1 point)
O%
25%
50% =my answer
75%




7.Watson and Crick were the first to suggest that DNA is __________. (1 point)
a short molecule
the shape of a double helix = my answer
a protein molecule
the genetic material




8.A DNA segment is changed from -AATTAG- to -AAATAG. This is a ________. (1 point)
frameshift mutation
point mutation
inversion =my answer
deletion




9.Which of the following situations is most usual for a dominant allele that results in severe effects in the offspring? (1 point)
both parents have the trait
only a single offspring has the trait =my answer
The trait occures by mutation
none of these




10.Sickle cell anemia is a genetic disease common to human populations from Africa and the Mediterranean coast. The incidence in greater in these regions than elsewhere because the heterozygouse state provides protection against malaria. Individuals affected with sickle cell anemia __________. (1 point)
are two times more likely to be males than females.
will not exhibit the symptomes of the disease until around the age 40.
suffer tissue damage resulting from oxygen deprivation =my answer
lack an enzyme that breaks dowm a lipid produced in the central nervous system.




11.A phenotypic ratio that results from a single dominant allele is _________. (1 point)
attached earlobes
More frequent in it's appearance
cystic fibrosis =my answer
polydactyly




12.Whose chromosomes determine the sex of offspring in humans? (1 point)
mother's
father's
both parents' = my answer
neither parents'




13.Which of the following genetic disorders can be detected by karotyping? (1 point)
Down Syndrome and Turner Syndrome
Tay- Sachs and PKU
hemophilia and cystic fibrosis= my answer
Klinefelter syndrome and sickle- cell anemia




14.Two healthy parents produce a child with the genetic disorder cystic fibrosis, which is the result of a recessive gene. What would be the best explaination for this inheritance? (1 point)
This is not the result of a genetic disorder
Both of the parents carried the gene for cystic fibriosis =my answer
Cystic fibrosis is a chromosomal mutation that occured during developement and is not related to the parental genotypes
Cystic fibrosis is caused by a mutation in the 21st pair of chromosomes




15.Both hemophilia and red- green color blindness are __________. (1 point)
inherited only from the mother =my answer
located on the Y- chromosome
caused by a dominant gene
sex- linked conditions




16.The chromosome abnormality that occurs when part of one chromosome breaks off and is added to a different chromosome is ________. (1 point)
deletion
nondisjunction = my answer
translocation
inversion




17.A reason that a fetus affected with PKU is not affected until afeter birth is that __________. (1 point)
The child is not bruised of cut during developement and therefor does not require aclotting factor= my answer  
prior to birth, the mother's enzyme level prevents accumulation of the dangerous chemical
The missing chromosome is compensated for by the mother prior to delivery
Because the fetus does not breath the accumulation of mucus in the lungs is not dangerous  

Answer
You missed 11 dwayne; I followed them in order. If I put a c you got it right
1Inc dominance
2c
3PKU
4c
5GUanine cytosine
6c
7c
8 Pt mutation
9 Both parents
10 c
11.Polydactyly (I am not sure about this one
12Father
13 Downs and Turners
14 c
15 sex linked
16 translocation
17 mother enzyme prevents