BIOD 210 FINAL EXAM
Explain briefly how the idea of epigenesis and preformation directly contradict each
other: - answer Preformation postulated that a fertilized egg contained a miniaturized
version of a tiny human, called homunculus. Epigenesis directly contradicted that theory
by stating that a fertilized egg undergoes a series of developmental events that
eventually form a human
Which of the following statements is correct?
- The X chromosome is much larger than the Y chromosome.
- The X and Y chromosomes share no homology.
- The X chromosome is the driving determinant for sex of an offspring.
Incorrect segregation of X and Y chromosomes (for instance a female with XXX or X
genotype) is always embryonic lethal - answerThe X chromosome is much larger than
the Y chromosome.
The DNA in a ________ is packaged in the head, which is shaped like a capsule. The
_________ of the phage pushes the DNA through the host cell membrane much like a
syringe. - answer- phage
- sheath
The only trisomy disorder in which individuals routinely live longer than one year is
_________.The incidence seems to increase with _____________. - answer- Down
syndrome (trisomy 21)
- maternal age
TRUE/FALSE: Epigenetic therapy does not depend on changes in the DNA sequence. -
answerTrue
In a few sentences, summarize Darwin's theory of natural selection - answer
Consider genes A, B and C which are located on a chromosome in that order. If genes
A andB cross over 40% of the time, and genes B and C cross over 30% of the time,
what is the probability of a double crossover between A,B, and C?: -
answer(0.4)*(0.3)=0.12, 12% chance of this crossover.
An enzyme that can be turned off by appropriate signals or conditions is called -
answerrepressible
The loss or gain of one chromosome, but not the set, is referred to as -
answeraneuploidy
2n-1 - answermonosomy
Explain briefly how the idea of epigenesis and preformation directly contradict each
other: - answer Preformation postulated that a fertilized egg contained a miniaturized
version of a tiny human, called homunculus. Epigenesis directly contradicted that theory
by stating that a fertilized egg undergoes a series of developmental events that
eventually form a human
Which of the following statements is correct?
- The X chromosome is much larger than the Y chromosome.
- The X and Y chromosomes share no homology.
- The X chromosome is the driving determinant for sex of an offspring.
Incorrect segregation of X and Y chromosomes (for instance a female with XXX or X
genotype) is always embryonic lethal - answerThe X chromosome is much larger than
the Y chromosome.
The DNA in a ________ is packaged in the head, which is shaped like a capsule. The
_________ of the phage pushes the DNA through the host cell membrane much like a
syringe. - answer- phage
- sheath
The only trisomy disorder in which individuals routinely live longer than one year is
_________.The incidence seems to increase with _____________. - answer- Down
syndrome (trisomy 21)
- maternal age
TRUE/FALSE: Epigenetic therapy does not depend on changes in the DNA sequence. -
answerTrue
In a few sentences, summarize Darwin's theory of natural selection - answer
Consider genes A, B and C which are located on a chromosome in that order. If genes
A andB cross over 40% of the time, and genes B and C cross over 30% of the time,
what is the probability of a double crossover between A,B, and C?: -
answer(0.4)*(0.3)=0.12, 12% chance of this crossover.
An enzyme that can be turned off by appropriate signals or conditions is called -
answerrepressible
The loss or gain of one chromosome, but not the set, is referred to as -
answeraneuploidy
2n-1 - answermonosomy
