Exam 4: Chapter 10, 11, +12

Question 1

Gametes are ___ cells formed by ____.
A) haploid; mitosis
B) diploid; mitosis
C) haploid; meiosis
D) diploid; meiosis
E) none of the above

Answer 1

C) haploid; meiosis

Question 2

How many total chromosomes does a normal diploid human cell have?
A) 23
B) 24
C) 46
D) 48
E) 56

Answer 2

C) 46

Question 3

What combination of sex chromosomes do genetically normal human females have?
A) XX
B) XY
C) YY
D) XO
E) ZW

Answer 3

A) XX

Question 4

Which of the following statements about meiosis is NOT TRUE?
A) it is performed ONLY by reproductive cells
B) it consists of two consecutive rounds of cell division
C) crossing-over may occur during meiosis 1
D) It is a “conservative” cell division
E) it produced haploid gametes

Answer 4

D) It is a “conservative” cell division

Question 5

A fertilized egg is called a(n)
A) gamete
B) ascomycete
C) tetrad
D) fetus
E) zygote

Answer 5

E) zygote

Question 6

Crossing-over is the physical exchange of genetic material that occurs only between
A) non-homologous, sister chromatids
B) homologous, sister chromatids
C) non-homologous, non-sister chromatids
D) homologous, non-sister chromatids
E) all of the above

Answer 6

D) homologous, non-sister chromatids

Question 7

The first stage of meiosis is
A) anaphase 1
B) prophase 1
C) metaphase 1
D) telophase 1
E) interkinesis

Answer 7

B) prophase 1

Question 8

During which stage of meiosis do the tetrads line up along the middle of the cell?
A) telophase 1
B) metaphase 1
C) telophase 2
D) metaphase 2
E) none of the above

Answer 8

B) metaphase 1

Question 9

Which of the following organelles did you inherit exclusively from your mother?
A) mitochondria
B) endoplasmic reticulum
C) Golgi body
D) ribosomes
E) all of the above

Answer 9

E) all of the above

Question 10

Which of the following is an enlarged micrograph depicting a person’s chromosomes organized by type. It may be used by a geneticist to diagnose a chromosomal defect.
A) genotype
B) karyotype
C) allotype
D) haplotype
E) phenotype

Answer 10

B) karyotype

Question 11

Sperm formation occurs in ____; egg formation occurs in _____.
A) testes; ovaries
B) testes; oviducts
C) ovaries; testes
D) oviducts; testes
E) lymph nodes; lymph nodes

Answer 11

A) testes; ovaries

Question 12

Upon the completion of meiosis, one spermatagonium normally produces
A) 1 egg and 1 sperm
B) 4 eggs
C) 4 sperm
D) 1 sperm
E) 1 sperm and 3 polar bodies

Answer 12

C) 4 sperm

Question 13

Polar bodies develop into
A) eggs
B) sperm
C) eggs and sperm
D) somatic cells
E) none of the above

Answer 13

E) none of the above

Question 14

Nondisjunction is defined as
A) the failure of daughter cells to separate during cell division
B) the failure of paired chromosomes to separate during cell division
C) the failure of nuclei to assemble or disassemble during cell division
D) the failure of a mitotic spindle to assemble during cell division
E) the failure of paired chromosomes to aligh along the metaphase plate during cell division

Answer 14

B) the failure of paired chromosomes to separate during cell division

Question 15

Individuals with Down Syndrome have a total of
A) one copy of chromosome 21
B) two copies of chromosome 21
C) three copies of chromosome 21
D) four copies of chromosome 21
E) none of the above

Answer 15

C) three copies of chromosome 21

Question 16

Individuals with Turner syndrome are genetically
A) males with one Y chromosome and two or more X chromosomes
B) males with one X chromosome and two or more Y chromosomes
C) females with one X chromosome only
D) females with one Y chromosome and two or more X chromosomes
E) females with three X chromosomes

Answer 16

C) females with one X chromosome only

Question 17

Gregor Mendel’s genetic experiments were performed using
A) fruit flies
B) mice
C) pea plants
D) guinea pigs
E) bacteria

Answer 17

C) pea plants

Question 18

Any non-sex chromosome is called a(n)
A) autosome
B) ribosome
C) microsome
D) centrosome
E) histone

Answer 18

A) autosome

Question 19

Different versions of the same genes are called
A) autosomes
B) anthers
C) centromeres
D) histones
E) alleles

Answer 19

E) alleles

Question 20

The physical location of a gene on a chromosome is called a(n)
A) allele
B) locus
C) karyotype
D) zygote
E) histone

Answer 20

B) locus

Question 21

Which of the following human diseases is X-linked?
A) Marfan syndrome
B) cystic fibrosis
C) sickle cell disease
D) hemophilia
E) all of the above

Answer 21

D) hemophilia

Question 22

Sickle-cell disease in humans demonstrates
A) X-linked alleles
B) Y-linked alleles
C) polygenic inheritance
D) codominance
E) heterozygote advantage

Answer 22

E) heterozygote advantage

Question 23

How many hydrogen bonds form between a cytosine (C) and guanine (G) base pair?
A) 1
B) 2
C) 3
D) 4
E) 5

Answer 23

C) 3

Question 24

The four main types of RNA are mRNA, rRNA, snRNA, and
A) bRNA
B) fRNA
C) kRNA
D) pRNA
E) tRNA

Answer 24

E) tRNA

Question 25

Which nitrogen-containing base is present in RNA but absent from DNA? A) uracil B) cytosine C) adenine D) thymine E) guanine

Answer 25

A) uracil

Question 26

DNA molecules normally consist of A) one strand of amino acids B) two strands of amino acids C) one strand of nucleotides D) two strands of nucleotides E) none of the above

Answer 26

D) two strands of nucleotides

Question 27

The two ends of a single strand of DNA are designated A) 3' and 3' B) 4' and 4' C) 5' and 5' D) 3' and 4' E) 3' and 5'

Answer 27

E) 3' and 5'

Question 28

If the sequence of bases of one DNA strand is GCAAT, then what is the sequence of bases on the complementary DNA strand? A) GCAAT B) TACCG C) CGTTA D) ATGGC E) CGUUA

Answer 28

C) CGTTA

Question 29

DNA replication is A) conservative B) nonconservative C) semiconservative D) dispersive E) none of the above

Answer 29

C) semiconservative

Question 30

Which of the following statements about normal DNA molecules is TRUE? A) DNA molecules consist of 3 strands B) the strands in a DNA molecule are antiparallel C) the strands ina DNA molecules are held together by disulfide bonds D) DNA molecules are left-handed helices E) DNA molecules contain 5 types of grooves

Answer 30

B) the strands in a DNA molecule are antiparallel

Question 31

In prokaryotes, DNA replication occurs A) in the cytoplasm B) in the golgi body C) in the endoplasmic reticulum D) in the nucleus E) all of the above

Answer 31

A) in the cytoplasm

Question 32

In eukaryotes, DNA replication occurs A) in the cytoplasm B) in the golgi body C) in the endoplasmic reticulum D) in the nucleus E) all of the above

Answer 32

D) in the nucleus

Question 33

The enzyme that unwinds DNA during replication and transcription is A) helicase B) RNA polymerase C) DNA polymerase D) DNA ligase E) rubisco

Answer 33

A) helicase

Question 34

The enzyme that copies DNA molecules into DNA is A) helicase B) RNA polymerase C) DNA polymerase D) DNA ligase E) rubisco

Answer 34

C) DNA polymerase

Question 35

The enzyme that transcribes DNA molecules into mRNA is A) helicase B) RNA polymerase C) DNA polymerase D) DNA ligase E) rubisco

Answer 35

B) RNA polymerase

Question 36

The enzyme that stitches together the DNA fragments on the lagging strand during DNA replication is A) helicase B) RNA polymerase C) DNA polymerase D) DNA ligase E) rubisco

Answer 36

D) DNA ligase

Question 37

Which segments in mRNA are removed during splicing? A) introns B) exons C) origins of replication D) promoters E) none of the above

Answer 37

A) introns

Question 38

The "tail" attached to the 3' end of eukaryotic mRNA molecules consists of 150-200 A) A nucleotides B) C nucleotides C) G nucleotides D) U nucleotides E) T nucleotides

Answer 38

A) A nucleotides

Question 39

How many molecules make up each codon in the genetic code? A) 3 B) 4 C) 20 D) 46 E) 64

Answer 39

A) 3

Question 40

How many unique codons make up the genetic code in total? A) 3 B) 4 C) 20 D) 46 E) 64

Answer 40

E) 64

Question 41

Which type of RNA is translated into protein? A) snRNA B) rRNA C) mRNA D) all of the above E) none of the above

Answer 41

C) mRNA

Question 42

Ribosomes translate one codon into A) one nucleotide B) three nucleotides C) one amino acid D) three amino acids E) none of the above

Answer 42

C) one amino acid