Question 1

Day length and temperature are both potential environmental signals that may influence development. What do changes in these two environmental factors tell an organism about future conditions?

Accepted Answer

The answer of Day length and temperature are both potential...

Question 2

Which of the following statements is correct?

Accepted Answer

Studies have shown that wings evolved as modifications to already existing structures, such as forelimbs, in different groups of animals. This is supported by the fact that wings in different groups have different skeletal components and varying degrees of similarity in their structural components. Therefore, statement A, B, D, and E are incorrect.

Question 3

Which of the following statements is false?

Accepted Answer

This statement is false. Many morphological differences among species have been linked to differences in Hox gene expression patterns caused by mutations.

Question 4

Genetic switches

Accepted Answer

Genetic switches (such as enhancers and repressors) play a crucial role in regulating gene expression and determining the fate of cells during development. They can help various modules (groups of cells or tissues) in the embryo to develop differently by turning on or off specific genes. This contributes to the overall complexity and diversity of multicellular organisms. Switches do not stop development altogether, nor do they ensure that all modules develop into the same type. They often involve promoters and transcription factors, although not exclusively. Lastly, genetic switches are essential for integrating positional information in the embryo by responding to signals from adjacent cells and tissues.

Question 5

Why do scientists consider the gene eyeless in fruit flies and the gene Pax6 in mice to be homologous?

Accepted Answer

The answer of Why do scientists consider the gene eyeless...

Question 6

Homologous genes

Accepted Answer

Homologous genes evolved from a gene present in a common ancestor, meaning they share a common ancestral origin. They may be found on the same chromosome or on different ones, and they can involve sets of genes (such as gene families). Homologous genes are not exclusive to mammals and they may or may not be expressed at the same time in an organism.

Question 7

Why do insects have legs only on thoracic segments, whereas centipedes have legs on thoracic and abdominal segments?

Accepted Answer

The answer of Why do insects have legs only on...

Question 8

Which of the following statements is false?

Accepted Answer

Environmental conditions do not directly induce the loss of body armor in freshwater sticklebacks; rather, it is due to genetic changes such as mutations affecting genes like Pitx1.

Question 9

There are morphological differences between adult chickens and ducks that relate to the duck's aquatic lifestyle. Why were these adaptations able to occur without influencing the development of the rest of the duck's morphology?

Accepted Answer

The answer of There are morphological differences between adult chickens...

Question 10

Developmental plasticity

Accepted Answer

Developmental plasticity is the ability of an organism to change its development in response to environmental conditions. It is not limited to plants and does not involve changing genotypes. It is also not called genotypic plasticity, which refers to the ability of a genotype to produce multiple phenotypes in different environments.

Question 11

Which of the following statements is false?

Accepted Answer

The cycle by which deer form and lose their antlers is primarily influenced by changes in day length (photoperiod), not temperature.

Question 12

_______ genes are involved in the development of the anterior-posterior axis in mammals and insects.

Accepted Answer

Hox genes are known for their role in the development of the anterior-posterior axis in both mammals and insects. They are responsible for the developmental patterning of body segments and the formation of different body structures in different segments.

Question 13

Temperature-determined sex

Accepted Answer

Temperature-determined sex is an example of developmental plasticity, where environmental cues can affect the development of an organism. It is not fixed genetically and can be altered by changing the temperature during a critical period of development.

Question 14

Genes that regulate development are highly conserved. This means that

Accepted Answer

The statement "highly conserved" means that the genes have changed very little over the course of evolution, indicating that choice B is the best answer. The other answer choices are not supported by the given statement.

Question 15

The difference in appearance of Nemoria arizonaria caterpillars in spring and summer is triggered by

Accepted Answer

The difference in appearance of Nemoria arizonaria caterpillars is triggered by the relative availability of food, which changes with the seasons.

Question 16

Heterochrony

Accepted Answer

Heterochrony can explain the long neck of the giraffe, involves shifts in the relative timing of developmental processes, can lead to major morphological changes and new lifestyles, and can explain whether webbing remains between the digits of adult salamanders and birds.

Question 17

Conservation efforts to restore sea turtle populations often rely on collecting eggs, incubating them in captivity, and then releasing hatchlings. Why would knowledge of temperature-determined sex be critical to such efforts?

Accepted Answer

The answer of Conservation efforts to restore sea turtle populations...

Question 18

Which of the following statements is false?

Accepted Answer

The gene Gremlin is not expressed in the webbing of chicken embryos, which is why chickens do not have webbed feet.

Question 19

Module development has allowed for evolutionary changes to occur while still resulting in a viable organism because

Accepted Answer

Modules can change independently of one another, allowing for evolutionary changes to occur without disrupting the entire organism. This is known as modular construction, where different modules can evolve at different rates and in different directions without affecting the whole organism.

Question 20

Which of the following statements is true?

Accepted Answer

Development continues until an organism dies. While the rate and extent of development may vary depending on the organism and its environment, development generally continues throughout an organism's entire lifespan. This includes ongoing processes such as cell division, growth, and differentiation, as well as changes in behavior and physiology that may be influenced by environmental factors. Therefore, statement B is the correct choice.

Quiz 20: Development and Evolutionary Change

Day length and temperature are both potential environmental signals that may influence development. What do changes in these two environmental factors tell an organism about future conditions?

Which of the following statements is correct?

Which of the following statements is false?

Genetic switches

Why do scientists consider the gene eyeless in fruit flies and the gene Pax6 in mice to be homologous?

Homologous genes

Why do insects have legs only on thoracic segments, whereas centipedes have legs on thoracic and abdominal segments?

Which of the following statements is false?

There are morphological differences between adult chickens and ducks that relate to the duck's aquatic lifestyle. Why were these adaptations able to occur without influencing the development of the rest of the duck's morphology?

Developmental plasticity

Which of the following statements is false?

_______ genes are involved in the development of the anterior-posterior axis in mammals and insects.

Temperature-determined sex

Genes that regulate development are highly conserved. This means that

The difference in appearance of Nemoria arizonaria caterpillars in spring and summer is triggered by

Heterochrony

Conservation efforts to restore sea turtle populations often rely on collecting eggs, incubating them in captivity, and then releasing hatchlings. Why would knowledge of temperature-determined sex be critical to such efforts?

Which of the following statements is false?

Module development has allowed for evolutionary changes to occur while still resulting in a viable organism because

Which of the following statements is true?