Exam 2 &nbs

							Exam 4                                                                                       Basics of Life 241
Covers Mitosis, Meiosis, Mendelian Genetics

1 What is the SOURCE of new genes in eukaryotes?
 A) separation of the homologous pairs
 B) mutation
 C) independent assortment
 D) A and B
 E) A, B, and C

2 What is the SOURCE of GENETIC VARIATION between individuals in eukaryotes?
  A) crossing over
  B) mutation
  C) independent assortment
  D) A and B
  E) A, B, and C

Shown to the right are two diploid cells (right and left) each with 4 chromosomes. There
are two types of chromosomes, long and short, in both cells. On the left is a diploid cell
with duplicated chromosomes. On the right is a diploid cell with unduplicated
chromosomes. Now, choose the correct chromosomal conditions for the following stages:

3 The
  prophase of
  mitosis:



                               A                B               C                D           E


4 A possible
  daughter
  cell of
  mitosis:


                                   A                B               C                D           E


5 A possible
  daughter
  cell of
  meiosis I:


                                   A                B               C                D           E


6 A possible
  daughter
  cell of
  meiosis II:


                                   A                B               C                D           E
     7   Which of the following IS NOT one of the features of Mendel’s experiments with garden peas that makes Mendel’s
         system an excellent system for studying genetics: A) The peas are self fertile and cross fertile. B) Pollination can be
         easily controlled. C) Peas have a very rapid (35 day) life cycle. D) Mendel chose the “right” traits to study. E)
         Mendel started with true-breeding strains.

     8   A strain (variety) of an organism which, when self-fertilized, only produces offspring with the given trait is called a:
         A) true-breeding strain. B) heterozygote. C) test cross. D) F1 generation. E) none of the above.

9    You have crossed true-breeding white flowered plants with true-breeding purple flowered plants. All of the F1 generation
     had purple flowers. When you crossed these purple flowered F1 plants with themselves, the F2 offspring had mostly
     purple flowers (748 purple flowered plants), but some (255) had white flowers. From these two crosses you correctly
     concluded: A) Purple flowers are dominant to white flowers. B) White flowers are recessive to purple flowers. C) The
     gene for white flowers was masked by the dominant allele in the F1 plants. D) The F1 plants are heterozygous. E) All of
     the above.

10    In question #9 above, what can be said of the white flowered F2 plants? A) They are homozygous recessive. B) They are
     heterozygous. C) They are now dominant. D) All of the above. E) None of the above.

11 What is plotted on the axes of a Punnett Square? A) All possible gametes produced by the male on one axis versus all
   possible gametes produced by the female on other axis. B) The probability of X chromosomes on one axis and the
   probability of the Y chromosomes on the other axis. C) The X chromosome genes are plotted on one axis and the the Y
   chromosome genes are plotted on the other axis.. D) Genes of the F1 are plotted on one axis and genes of the F2 are
   plotted on the other axis. E) None of the above.

12    Hairy toes (H) is dominant to hairless toes (h). If a hairy toed man whose mother had hairless toes marries a woman with
     hairless toes, what fraction of their children will be expected to have hairy toes? A) None of their children will be
     expected have hairy toes. B) Half of their children will be expected to have hairy toes. C) All of their children will be
     expected to have hairy toes.. D) none of the above.

13 Which stage of meiosis explains Mendel’s Law of Independent Assortment? A) meiosis I. B) meiosis II. C) telophase II.
   D) prophase II. E) prophase I.

14 Which stage of meiosis explains Mendel’s Law of Segregation? A) meiosis I. B) meiosis II. C) telophase II. D) prophase
   II. E) prophase I.

15 Shown to the right is a Punnett square like one that you have seen in class.
   What is the genotype of the parent pea plant labeled “X”? A) GG B) Gg
   C) gg D) G E) g

16 Shown to the right is a Punnett square like one that you have seen in class.
   The G allele is: A) DNA that codes for the green color B) the dominant
   allele C) expressed in the homozygous condition D) expressed in the
   heterozygous condition E) all of the above

17 Shown to the right is a Punnett square like one that you have seen in class.
   How is the genotype of the light colored pea plant properly described?
   A) homozygous dominant for yellow color B) heterozygous for yellow
   color. C) homozygous recessive for the yellow color. D) all of the above.
   E) none of the above.

18 Shown to the right is a Punnett square like one that you have seen in class. What is the phenotype of the parent pea labeled
   Y? A) green B) yellow C) Gg D) G E) g
19 When does a scientist use a TESTCROSS? A) to determine the genotype of an organism that is homozygous recessive for
   a trait. B) to determine the genotype of an organism that is homozygous dominant for a trait. C) to determine the genotype
   of an organism that is known to be heterozygous for a trait. D) to determine the genotype of an organism that expresses a
   dominant trait but that has an unknown genotype


20 Shown to the right is an experiment that Mendel did.
   What major discovery was specifically based on this
   type of experiment? A) alleles of different genes
   assort independently of one another during gamete
   formation B) alleles separate such that each
   gamete gets only one member of the pair of alleles
   C) Law of Segregation D) none of the above

21 Shown to the right is an experiment that Mendel did.
   What is the genotype of the pea plant labeled Y?
   A) GgYy B) GGYY C) yyYYD) GGgg E) Both
   “C” and “D”

22 Shown to the right is an experiment that Mendel did.
   The experiment results are associated with a 9:3:3:1
   ratio. What is this 9:3:3:1 ratio? A) the ratio of the
   genotypes of that are produced by this cross. B) the
   ratio of the phenotypes that are produced by this
   cross. C) the genotypes of the X individual. D) the
   phenotype of the Y individual. E) All of the above.

23 The instructor’s mother has blood type AB.
   Therefore, she must have and express both the IA
   and the IB allele. This situation is an example of :
   A) One gene being dominant and the other being
   recessive. B) Genetic co-dominance. C) Linkage.
   D) Epistasis. E) Sex linkage

24 Lethal alleles usually give rise to: A) enzymes. B) malfunctioning or non-functioning proteins. C) dead genes. D)
   dominant traits. E) All of the above

25 Does the law of independent assortment hold for closely linked genes? A) No B) Yes C) Yes, but only when the linkage is
   very close. D) Yes, but only when the map distance between the linked genes is very small.

26 What separates during meiosis I? A) the chromatids of duplicated chromosomes B) the homologous pairs of
   chromosomes C) DNA strands of the double helix D) sex cells

27 What separates during meiosis II? A) the chromatids of duplicated chromosomes B) the homologous pairs of
   chromosomes C) DNA strands of the double helix D) sex cells

28 What separates during mitosis? A) the chromatids of duplicated chromosomes B) the homologous pairs of chromosomes
   C) DNA strands of the double helix D) sex cells

29 Which stage of meiosis is most like mitosis? A) meiosis I B) meiosis II C) Prophase I D) Anaphase I E) the S phase
   between meiosis I and meiosis II

30 The long threadlike structures (highly condensed during mitosis) that are made of DNA & protein and that are found in the
   nucleus during interphase are called_________________? A) chromatids B) chromosomes C) genes D) chromatin E)
   centromeres
31 Shown to the right is part of a larger
   structure that you have studied. What is the
   larger structure called? A) an enzyme B) a
   chromosome C) a protein D) chromatin E)
   centromeres

32 The instructor’s wife has blood type A.
   What is her genotype? A) IAIA B) IA i
   C) either IAIA or IA i D) can’t tell from the
   information given

33 When a pair of homologous chromosomes
   comes together in tight association during prophase I the resulting structure is called _____________? A) a chromosome
   B) a chromatid C) a chromatiod body D) a tetrad E) Both “C” and “D”

34 What type of cell undergoes cytokinesis by forming a cell plate. A) any dividing cell B) a dividing plant cell C) a
   dividing animal cell D) a human cell E) Both “C” and “D”

35 If a given cell has pairs of unduplicated homologous chromosomes, the cell is said to be ___________? A) haploid. B)
   diploid. C) monoploid. D) biploid. E) duoploid.

36 Most human body cells contain unduplicated chromosomes. These cells are ___________? A) haploid. B) diploid. C)
   monoploid. D) biploid. E) duoploid.

37 Humans have 23 different types of chromosomes. What can be said about chromosome type 19? A) Each individual has
   two type 19 chromosomes, one from each parent. B) Type 19 chromosomes can either be in the duplicated or the
   unduplicated state, depending on the cell cycle. C) Both of the type 19 chromosomes carry genes for the same traits. D)
   All of the above are true. E) None of the above are true.

38 When does synapsis occur? A) prophase. B) prophase I. C) prophase II. D) metaphase. D) metaphase II.

39 What when does crossing over occur? A) prophase. B) prophase I. C) prophase II. D) metaphase. D) metaphase II.

40 What occurs during “S phase”? A) synapsis. B) synchrony. C) chromosome duplication. D) DNA synthesis. E) Both
   “C” and “D”.

41 Which of the following IS NOT a function of the many proteins that are found bound to DNA molecules in the cell? A)
   protection of the DNA B) packaging the DNA C) duplication of the DNA D) transcription of the DNA into RNA E) All
   of the above are functions of the proteins found binding to DNA.

42 What can be said about the two sister chromatids of a duplicated chromosome? A) They have IDENTICAL DNA
   molecules. B) They have similar, but not identical DNA molecules. C) They have genes for the same traits, one set from
   the mother and the other set from the father. D) All of the above. E) None of the above.

43 Which of the following is true of kinetochores? A) They are found associated with the centromere of each chromosome.
   B) They are proteins that attach to the spindle. C) They are molecular motors that pull chromosomes toward the poles. D)
   All of the above. E) None of the above.

44 What proteins aggregate together to form the spindle. A) actin and myosin. B) alpha and beta tubulin. C) intermediate
   filaments. D) microfilaments. E) None of the above.

45 What is true of sexual reproduction? A) The offspring are almost all genetically identical to the parent. B) There is great
   genetic variation in the offspring. C) The genetic variation in the offspring comes primarily from mutations. D) All of the
   above. E) None of the above.
Shown to the right are two diploid cells (right and left) each with 4 chromosomes. There
are two types of chromosomes, long and short, in both cells. On the left is a diploid cell
with duplicated chromosomes. On the right is a diploid cell with unduplicated
chromosomes. Now, choose the correct chromosomal conditions for the following stages:

46 The G1 of
interphase:




                           A               B                C               D                E


47 The G2 of
interphase:




                           A               B                C               D                E


48 A cell in prophase I:




                           A               B                C               D                E


49 A possible
  daughter
  cell in
  prophase II:


                                 A                B               C                D             E




50 What is true of the two chromosomes seen in the
cartoon to the right? A) They are homologous
chromosomes. B) They are duplicated chromosomes. C)
The two chromosomes originally came from different
parents. D) Both “A” and “B”. E) All of the above.