問題一覧
1
Polyploidy refers to:
An individual with complete extra sets of chromosomes
2
What is true for the chromosomes?
The DNA sequence of the two sister chromatids are identical
3
In a population expressing five different alleles for a particular gene, how many alleles may be present in each diploid organism in the population?
2
4
In meiosis I anaphase:
Homologous chromosomes move toward opposite poles
5
During anaphase II (meiosis II)
Sisterchromatidsseparateandmigratetowardsoppositepoles
6
A man with type A blood marries a woman with type B blood. If both parent are homozygous, their offspring will have type _____ blood, which is an example of ___
AB; codominance
7
During the mitosis the spindle fibers connect to the:
kinetochores
8
TRUE for cell cycles
The DNA content of the cell is duplicated before mitosis.
9
The number of chromosomes in a zygote is
The same as in a skincell
10
Choose the correct statement for the M-phase
At the beginning of prophase the nuclear envelope disintegrates
11
A disease caused by an autosomal non-disjunction is
Down syndrome
12
A human genetic defect that is caused by non-disjunction of sex chromosome is
Turner syndrome
13
In which phase or stage do sister chromatids separate during meiosis?
In anaphase II
14
How many tetrads are found in meiotic prophase in an organism with a diploid number of 12?
6
15
Homologous chromosomes are NOT necessarily identical in their _______
alleles
16
The human genome is:
All of our DNA
17
Klinefelter’s syndrome (XXY) is an example of chromosomal aneuploidy that can readily be diagnosed by:
Karyotyping
18
A 47, XXY karyotype may be caused by the non-disjunction of __________
Meiosis II in either parent
19
What is true about sister chromatid exchange?
It has no genetic consequence in most of the cases
20
Alleles that are both expressed in a heterozygote are
Codominant
21
In meiosis, what is meant by a tetras of homologous chromosomes?
Four chromatids in the unit
22
Which of these statements about the difference between mitosis and meiosis is true?
Sister chromatids separate during mitosis and meiosis II, but not during meiosis I
23
Which type of chromosome abnormality is characteristic for the centric fusion?
structural aberration
24
Which is not true for the structural chromosome aberrations?
One or more extra copy of chromosome is in the cell
25
Which cytoskeletal component play a crucial role in cytokinesis?
Actin and myosin filaments
26
Which stage of meiosis is the physical basis for Mendels law of independent assortment?
Anaphase I
27
Down syndrome results from:
Thepresenceofanextrachromosomeinposition21
28
What is not true for the cell cycle regulation?
Theinhibitoryphosphateisremovedbyactivatingkinase
29
Which proteins are encoded by tumor suppressor genes?
cycline dependent kinase inhibitors
30
What is true about kinetochore?
It is a protein complex added to the centromere region of chromosomes
31
Choose the correct statement for cell cycle
M-phase is completed after the inactivation of MPF
32
Differences between meiosis and mitosis include all of the following EXCEPT
Each mitotic cell division and each second meiotic division is preceded bya complete round of DNA synthesis
33
The number of DNA molecules in the nucleus of a diploid human cell in G1 phase
46
34
A synaptonemal complex is:
Aladderlikestructurethatformsinpairingofhomologouschromosomesmeiosis
35
Which is correct?
MPF triggers the mitosis and meiosis as well
36
What characterize the inactive MPF?
It is the substrate of kinases and a phosphatases
37
What is the requirement for passing the restriction point?
phosphorylation of pRb
38
give the number of chromosomes, a cell resulting from mitosis division of spermatogonium
46
39
give the number of chromosomes, a primaryoocyte
46
40
give the number of chromosomes, secondary soermatocyte
23
41
give the number of chromosomes, the polar body formed along with a secondary oocyte
23
42
give the number of chromosomes, a soeematid
23
43
give the number of chromosomes, a cell formed after soermiogenesis
23
44
What can be the consequence in the offspring, if one of the parents is a carrier for Robertsonian translocation between chromosome 14 and 21?
The offspring will either have Down syndrome or normal phenotype.
45
Burkitt lymphoma
reciprocal translocation
46
TGT to TGC (cys to cys)
silent
47
TGT to TGG cys to trp
missense
48
TGT to TGA
nonsense
49
GAG to GTG disease
sickle cell anemia