Bio 181 final latest update 2024/2025
1.Write out a short explanation of the chromosome theory of inheritance in relation to gene
transfer Correct answer. chromosomes are the vehicles of genetic heredity
2. List the number of chromosomes that are found in the following: human sperm cell, human egg
cell, and human zygote. Identify these as diploid or haploid cells Correct answer. human:
46(diploid)
sperm: 23(haploid)
human egg: 23(haploid)
human zygote: 23(diploid)
3. Contrast between genes and alleles and identify them in relation to a chromosome Correct
answer. Alleles are different forms of genes and determine which genes will be expressed
4. Homozygous alleles Correct answer. two identical alleles for a trait
5. Heterozygous alleles Correct answer. different alleles for that gene
6. Dominant allele Correct answer. An allele whose trait always shows up in the organism when
the allele is present.
7. Recessive allele Correct answer. An allele that is hidden whenever the dominant allele is
present
8. Complete dominace Correct answer. the dominant allele completely covers up the recessive
allele
9. Incomplete dominance Correct answer. Situation in which one allele is not completely
dominant over another allele
10. Genotype Correct answer. genetic makeup
11. Phenotype Correct answer. physical characteristics of an organism
12. Monohybrid Correct answer. An organism that is heterozygous with respect to a single gene
of interest. All the offspring from a cross between parents homozygous for different alleles are
monohybrids. For example, parents of genotypes AA and aa produce a monohybrid of genotype
Aa.
13. Dihybrid Correct answer. cross involving two traits
, 14. Parental generation Correct answer. P generation
15. First generation Correct answer. F1
16. Second generation Correct answer. F2
17. True breeding Correct answer. Organisms that, when reproducing, create offspring of all the
same variety.
18. Test cross Correct answer. the crossing of an individual of unknown genotype with a
homozygous recessive individual to determine the unknown genotype
19. Codominance Correct answer. A condition in which neither of two alleles of a gene is
dominant or recessive.
20. Polygenic inheritance Correct answer. occurs when multiple genes determine the phenotype
of a trait
21.Trisomy 21 Correct answer. Carrying an extra copy of chromosome 21; also known as Down
syndrome.
22. Griffith Correct answer. discovered bacterial transformation
23. Hershey-Chase Experiment Correct answer. Used radioactive material to label DNA and
protein; infected bacteria passed on DNA; helped prove that DNA is genetic material not proteins
24. Chargaff's Rule Correct answer. A=T and C=G
25. Watson and Crick Correct answer. Figured out structure of DNA was a double helix
26. Rosalind franklin Correct answer. Used X-ray diffraction to discover the double-helical
structure of DNA.
27. X-ray crystallography Correct answer. A technique used to study the three-dimensional
structure of molecules. It depends on the diffraction of an X-ray beam by the individual atoms of
a crystallized molecule.
28. Conservative DNA replication Correct answer. Leaves the original DNA molecule intact and
generates a completely new molecule.
29. Semi-conservative DNA replication Correct answer. refers to the two resulting molecules each
being made of one older "parent" strand and a new "daughter" strand
30. Dispersive DNA replication Correct answer. each daughter duplex contains interspersed
parental and daughter segments
31. Meselson-Stahl Experiment Correct answer. (1958) grew bacteria for one generation with
heavy nitrogen, transferred the bacteria to a medium with nitrogen for several generations then
1.Write out a short explanation of the chromosome theory of inheritance in relation to gene
transfer Correct answer. chromosomes are the vehicles of genetic heredity
2. List the number of chromosomes that are found in the following: human sperm cell, human egg
cell, and human zygote. Identify these as diploid or haploid cells Correct answer. human:
46(diploid)
sperm: 23(haploid)
human egg: 23(haploid)
human zygote: 23(diploid)
3. Contrast between genes and alleles and identify them in relation to a chromosome Correct
answer. Alleles are different forms of genes and determine which genes will be expressed
4. Homozygous alleles Correct answer. two identical alleles for a trait
5. Heterozygous alleles Correct answer. different alleles for that gene
6. Dominant allele Correct answer. An allele whose trait always shows up in the organism when
the allele is present.
7. Recessive allele Correct answer. An allele that is hidden whenever the dominant allele is
present
8. Complete dominace Correct answer. the dominant allele completely covers up the recessive
allele
9. Incomplete dominance Correct answer. Situation in which one allele is not completely
dominant over another allele
10. Genotype Correct answer. genetic makeup
11. Phenotype Correct answer. physical characteristics of an organism
12. Monohybrid Correct answer. An organism that is heterozygous with respect to a single gene
of interest. All the offspring from a cross between parents homozygous for different alleles are
monohybrids. For example, parents of genotypes AA and aa produce a monohybrid of genotype
Aa.
13. Dihybrid Correct answer. cross involving two traits
, 14. Parental generation Correct answer. P generation
15. First generation Correct answer. F1
16. Second generation Correct answer. F2
17. True breeding Correct answer. Organisms that, when reproducing, create offspring of all the
same variety.
18. Test cross Correct answer. the crossing of an individual of unknown genotype with a
homozygous recessive individual to determine the unknown genotype
19. Codominance Correct answer. A condition in which neither of two alleles of a gene is
dominant or recessive.
20. Polygenic inheritance Correct answer. occurs when multiple genes determine the phenotype
of a trait
21.Trisomy 21 Correct answer. Carrying an extra copy of chromosome 21; also known as Down
syndrome.
22. Griffith Correct answer. discovered bacterial transformation
23. Hershey-Chase Experiment Correct answer. Used radioactive material to label DNA and
protein; infected bacteria passed on DNA; helped prove that DNA is genetic material not proteins
24. Chargaff's Rule Correct answer. A=T and C=G
25. Watson and Crick Correct answer. Figured out structure of DNA was a double helix
26. Rosalind franklin Correct answer. Used X-ray diffraction to discover the double-helical
structure of DNA.
27. X-ray crystallography Correct answer. A technique used to study the three-dimensional
structure of molecules. It depends on the diffraction of an X-ray beam by the individual atoms of
a crystallized molecule.
28. Conservative DNA replication Correct answer. Leaves the original DNA molecule intact and
generates a completely new molecule.
29. Semi-conservative DNA replication Correct answer. refers to the two resulting molecules each
being made of one older "parent" strand and a new "daughter" strand
30. Dispersive DNA replication Correct answer. each daughter duplex contains interspersed
parental and daughter segments
31. Meselson-Stahl Experiment Correct answer. (1958) grew bacteria for one generation with
heavy nitrogen, transferred the bacteria to a medium with nitrogen for several generations then
