Bio chapter 14 test
What are the three steps in manipulating DNA?
-cutting DNA -separating DNA - reading DNA
What were two main goals of the Human Genome Project?
-sequence all 3 billion base pairs of human DNA - identifying all human genes
Which piece of DNA would move fastest in gel electrophoresis? A segment that is
100 base pairs long.
How many autosomal chromosomes will a normal human karyotype have, and how many sex chromosomes will a normal human karyotype have?
22 autosomal and 1 pair of sex chromosomes.
How many chromosomes are shown in a normal human karyotype?
46
According to Figure 14-1, what is the approximate probability that a human offspring will be female?
50%
If a couple has five boys, the probability that the next child will be a boy is ____________________.
50%
What percentage of human sperm cells carry an X chromosome?
50%
Which of the following statements is true?
A colorblind girl's father must be colorblind.
What prevents insurance companies from discriminating against people based on information derived from genetic tests?
Discrimination based on genetic information is against the law.
Which enzyme(s) in Figure 14-8 would be best for cutting DNA to make fragments with sticky ends?
EcoRI and BamI
In humans, the mother's gamete determines the sex of the offspring.
FALSE
When DNA fragments are separated by gel electrophoresis, the longest fragments move fastest.
FALSE FALSE
Which of the following is caused by a dominant allele?
Huntington's disease
Which of the following pairs of genotypes result in the same phenotype?
IBIB and IBi
A boy who is colorblind inherited the disorder from his ____________________.
Mother
What is an advantage to sickle cell disease and cystic fibrosis?
People that are heterozygous for sickle cell are resistant to malaria so they will not get that disease. People that are heterozygous for cystic fibrosis will not have the disorder and will be resistant to typhoid fever, which is caused by dirty water.
In a human karyotype, 44 of the chromosomes are autosomes.
TRUE
Why are males more likely to have a sex-linked disorder than a female?
The males only need to inherit one recessive trait on the X chromosome and they will show that trait. Females need to inherit two recessive alleles on the X chromosome in order to show that trait.
Cystic Fibrosis
The most common fatal genetic disorder that affects the breathing passageways and the digestive system
Huntington's disease
This disorder does not appear until mid 30's or 40's and results in a rapid breakdown of the nervous system. This disorder is a dominant allele disorder
If the gene for a recessive sex-linked trait was on the X chromosome, the trait would be more common in males than in females.
True
Information from the Human Genome Project can be used to learn more about human diseases.
True
A Barr body is an inactivated ____________________ chromosome.
X
Which of the following combinations of sex chromosomes represents a female?
XX
In humans, sex is determined by the X and ____________________ chromosomes.
Y
sickle cell anemia
a disorder that causes the shape of the blood cells to change from their normal shape. this disease can causes painfull clots and and posible loss of organs or life.
What new field is described by the overlap area in the Venn diagram in Figure 14-9?
bioinformatics
Sex-linked genes are located on
both the X chromosome and the Y chromosome.
Which was the first step in sequencing the human genome?
cutting the DNA into manageable pieces
In a pedigree, such as the one in Figure 14-4, a circle represents a(an)
female.
The study of whole genomes, including genes and their functions is known as _______________.
genomics
People who are heterozygous for sickle cell disease are generally healthy because they
have some normal hemoglobin in their red blood cells.
A cat that has spots of more than one color
is probably female.
A(An) ____________________ can be used to determine whether a person has inherited the normal number of chromosomes.
karyotype
Nondisjunction can lead to the disorder called ______________________________, in which a male has an extra X chromosome.
klinefelter's syndrome
The failure of chromosomes to separate during meiosis is called
nondisjunction.
Human females produce egg cells that have
one X chromosome.
The formation of a Barr body inactivates
one whole X chromosome in a female cell.
A(An) ____________________ is a diagram that follows the inheritance of a single gene through several generations of a family.
pedigree
Colorblindness is more common in males than in females because the allele for colorblindness is
recessive and located on the X chromosome.
Which of the following can be used to cut DNA so it can be studied?
restriction enzymes
The Human Genome Project is an attempt to
sequence the DNA of every human gene.
An advantage of using a restriction enzyme such as EcoR1 is that it creates ______________ that can match to complimentary base pairs.
sticky ends
Examine the pedigree in Figure 14-3. The allele for the presence of a white forelock is dominant. Therefore, we can tell from the chart that in the couple labeled 2
the male is heterozygous and the female is heterozygous.
color blindness
this disorder is a sex-link disorder that affects the vision of those that have it. this disorder is most commonly found in males.
hemophilia
this disorder is a sex-linked disorder that has a deficient protein that does not allow for the blood to clot properly
muscular dystrophy
this disorder is a sex-linked disorder that results in the muscles gradually weakening over time. this disorder is most common in males.
klinefelter's syndrome
this disorder is because the boy is born with an extra X chromosome,so they are XXY and they are not able to reproduce.
down syndrome
this disorder is because the individual is born with an extra chromosome 21
turner's syndrome
this disorder results in a female being born with only one X chromosome and the individual being sterile
A haplotype is a group of alleles found on the same chromosome that tends to be inherited altogether.
true
A female with the disorder _________________________ inherits only one X chromosome.
turner's syndrome
A human female inherits
two copies of every gene located on the X chromosome.
Because the X chromosome contains genes that are vital for normal development, no baby has been born
without an X chromosome.