
Concept explainers
Match each numbered item with the most closely related lettered item.
a. cytoplasmic segregation | 1. transmission of genes through maternal gametes only |
b. heteroplasmic | 2. cell that has mtDNA or cpDNAs that are all of one genotype |
c. homoplasmic | 3. having gametes of similar size |
d. maternal inheritance | 4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
e. uniparental inheritance | 5. a specific fraction of wild-type organellar DNAs is required for a wild-type |
f. isogamous | 6. cell with mtDNAs or cpDNAs with different genotypes. |
g. threshold effect | 7. Transmission of genes through either a maternal or a parental gamete ˗ not both. |

a.
To determine:
The phrase that describes “cytoplasmic segregation” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
A process in which a cell having many mitochondrial DNA produces a cell having single mitochondrial DNA.
Answer to Problem 1P
Correct answer:
Cytoplasmic segregation: a cell with a mixture of different mtDNAs generates a daughter cell with only one kind.
Explanation of Solution
The cytoplasmic segregation refers to a process where cell containing many different types of mitochondrial DNA result in the generation of a daughter cell, which consists of only one mitochondrial DNA.

b.
To determine:
The phrase that describes “heteroplasmic” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
A cell that possess mitochondrial and chlorplast DNA of different genotype.
Answer to Problem 1P
Correct answer:
Heteroplasmic: cell with mtDNAs or cpDNAs with different genotypes is called heteroplasmic.
Explanation of Solution
The heteroplasmic cell consists of either the mitochondrial DNA or the chloroplast DNA that comprises of different genotypes.

c.
To determine:
The phrase that describes “homoplasmic” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
A cell that possess mitochondrial and chlorplast DNA of same genotype is called homoplasmic.
Answer to Problem 1P
Correct answer:
homoplasmic: a cell with mtDNAs or cpDNAs all of one genotype.
Explanation of Solution
The homoplasmic cells refer to the eukaryotic cells that have identical mitochondrial and chloroplast DNA.

d.
To determine:
The phrase that describes “maternal inheritance” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
When the genes pass from one generation to next only through the means of maternal gametes, the process is called maternal inheritance.
Answer to Problem 1P
Correct answer:
maternal inheritance: transmission of genes through maternal gamete only.
Explanation of Solution
In the case of maternal inheritance, the genes that are transmitted to the offsprings are the ones that come from only the maternal gametes.

e.
To determine:
The phrase that describes “uniparental inheritance” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
When genes pass either through male or female or both the gametes, the process is called uniparental inheritance.
Answer to Problem 1P
Correct answer:
uniparental inheritance: transmission of genes through either a maternal or a parental gamete-not both.
Explanation of Solution
In case of uniparental inheritance, the transmission of genes only occurs by one of the parents. It can either be from mother or the father. In this type of inheritance, both the parents are not involved in transmission of genes to the offspring.

f.
To determine:
The phrase that describes “isogamous” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
Gametes having similar types of morphology are said to be isogamous.
Answer to Problem 1P
Correct answer:
isogasmous: having gametes of similar size.
Explanation of Solution
In biological terms the gametes that are similar morphologically that is in terms of their shape and size are termed as isogamous.

g.
To determine:
The phrase that describes “threshold effect” among the options given below.
1. transmission of genes through maternal gametes only. |
2. cell that has mtDNA or cpDNAs all of one genotype |
3. having gametes of similar size |
4. a cell with a mixture of different mtDNAs generates a daughter cell with only one kind. |
5. a specific fraction of wild-type organellar DNAs is required for a wild-type phenotype. |
6. cell with mtDNAs or cpDNAs with different genotypes. |
7. Transmission of genes through either a maternal or a parental gamete, but not both. |
Introduction:
When wild type phenotype is expressed with the help of wild type of organellar DNA, the process is called threshold effect.
Answer to Problem 1P
Correct answer:
threshold effect: a specific fraction of wild type organellar DNAs is required for a wild-type phenotype.
Explanation of Solution
The threshold effect refers to an approach where a small amount of wild type DNA is needed for the expression of a wild type phenotype.
Want to see more full solutions like this?
Chapter 14 Solutions
Genetics: From Genes to Genomes, 5th edition
- Design a grafting experiment to determine if limb mesoderm determines forelimb / hindlimb identity. Include the experiment, a control, and an interpretation in your answer.arrow_forwardThe Snapdragon is a popular garden flower that comes in a variety of colours, including red, yellow, and orange. The genotypes and associated phenotypes for some of these flowers are as follows: aabb: yellow AABB, AABb, AaBb, and AaBB: red AAbb and Aabb: orange aaBB: yellow aaBb: ? Based on this information, what would the phenotype of a Snapdragon with the genotype aaBb be and why? Question 21 options: orange because A is epistatic to B yellow because A is epistatic to B red because B is epistatic to A orange because B is epistatic to A red because A is epistatic to B yellow because B is epistatic to Aarrow_forwardA sample of blood was taken from the above individual and prepared for haemoglobin analysis. However, when water was added the cells did not lyse and looked normal in size and shape. The technician suspected that they had may have made an error in the protocol – what is the most likely explanation? The cell membranes are more resistant than normal. An isotonic solution had been added instead of water. A solution of 0.1 M NaCl had been added instead of water. Not enough water had been added to the red blood cell pellet. The man had sickle-cell anaemia.arrow_forward
- A sample of blood was taken from the above individual and prepared for haemoglobin analysis. However, when water was added the cells did not lyse and looked normal in size and shape. The technician suspected that they had may have made an error in the protocol – what is the most likely explanation? The cell membranes are more resistant than normal. An isotonic solution had been added instead of water. A solution of 0.1 M NaCl had been added instead of water. Not enough water had been added to the red blood cell pellet. The man had sickle-cell anaemia.arrow_forwardWith reference to their absorption spectra of the oxy haemoglobin intact line) and deoxyhemoglobin (broken line) shown in Figure 2 below, how would you best explain the reason why there are differences in the major peaks of the spectra? Figure 2. SPECTRA OF OXYGENATED AND DEOXYGENATED HAEMOGLOBIN OBTAINED WITH THE RECORDING SPECTROPHOTOMETER 1.4 Abs < 0.8 06 0.4 400 420 440 460 480 500 520 540 560 580 600 nm 1. The difference in the spectra is due to a pH change in the deoxy-haemoglobin due to uptake of CO2- 2. There is more oxygen-carrying plasma in the oxy-haemoglobin sample. 3. The change in Mr due to oxygen binding causes the oxy haemoglobin to have a higher absorbance peak. 4. Oxy-haemoglobin is contaminated by carbaminohemoglobin, and therefore has a higher absorbance peak 5. Oxy-haemoglobin absorbs more light of blue wavelengths and less of red wavelengths than deoxy-haemoglobinarrow_forwardWith reference to their absorption spectra of the oxy haemoglobin intact line) and deoxyhemoglobin (broken line) shown in Figure 2 below, how would you best explain the reason why there are differences in the major peaks of the spectra? Figure 2. SPECTRA OF OXYGENATED AND DEOXYGENATED HAEMOGLOBIN OBTAINED WITH THE RECORDING SPECTROPHOTOMETER 1.4 Abs < 0.8 06 0.4 400 420 440 460 480 500 520 540 560 580 600 nm 1. The difference in the spectra is due to a pH change in the deoxy-haemoglobin due to uptake of CO2- 2. There is more oxygen-carrying plasma in the oxy-haemoglobin sample. 3. The change in Mr due to oxygen binding causes the oxy haemoglobin to have a higher absorbance peak. 4. Oxy-haemoglobin is contaminated by carbaminohemoglobin, and therefore has a higher absorbance peak 5. Oxy-haemoglobin absorbs more light of blue wavelengths and less of red wavelengths than deoxy-haemoglobinarrow_forward
- Which ONE of the following is FALSE regarding haemoglobin? It has two alpha subunits and two beta subunits. The subunits are joined by disulphide bonds. Each subunit covalently binds a haem group. Conformational change in one subunit can be transmitted to another. There are many variant ("mutant") forms of haemoglobin that are not harmful.arrow_forwardWhich ONE of the following is FALSE regarding haemoglobin? It has two alpha subunits and two beta subunits. The subunits are joined by disulphide bonds. Each subunit covalently binds a haem group. Conformational change in one subunit can be transmitted to another. There are many variant ("mutant") forms of haemoglobin that are not harmful.arrow_forwardDuring a routine medical check up of a healthy man it was found that his haematocrit value was highly unusual – value of 60%. What one of the options below is the most likely reason? He will have a diet high in iron. He is likely to be suffering from anaemia. He lives at high altitude. He has recently recovered from an accident where he lost a lot of blood. He has a very large body size.arrow_forward
- Explain what age of culture is most likely to produce an endospore?arrow_forwardExplain why hot temperatures greater than 45 degrees celsius would not initiate the sporulation process in endospores?arrow_forwardEndospore stain: Consider tube 2 of the 7-day bacillus culture. After is was heated, it was incubated for 24 hours then refrigerated. Do you think the cloudiness in this tube is due mostly to vegetative cells or to endospores? Explain your reasoningarrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage LearningBiology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxBiology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage LearningBiology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage Learning





