Genetics Concepts and Principles

Dr. Ogden's lecture explores advanced genetic concepts beyond Mendelian genetics, including incomplete dominance, co-dominance, pleiotropy, polygenic inheritance, environmental influences, genetic recombination, and sex-linked traits. Examples such as snapdragons, Palomino horses, blood groups, sickle cell disease, and color blindness illustrate these concepts.

Which of the following topics is NOT covered in the lecture on genetics beyond Mendelian principles?

• Photosynthesis

• Codominance

• Genetic recombination

• Incomplete dominance

In incomplete dominance, what is the result of crossing a pure red flower with a pure white flower?

• No flowers

• Pink flowers

• White flowers

• Red flowers

What is a key difference between incomplete dominance and codominance?

• Incomplete dominance results in both traits being fully expressed, while codominance results in a blend of traits.

• Incomplete dominance results in a blend of traits, while codominance results in both traits being fully expressed.

• Both result in one trait being dominant over the other.

• Both result in a blend of traits.

Which genetic phenomenon is exemplified by sickle cell disease?

• Codominance

• Pleiotropy

• Incomplete dominance

• Polygenic inheritance

What does polygenic inheritance involve?

• Multiple genes affecting multiple traits

• One gene affecting one trait

• Multiple genes affecting one trait

• One gene affecting multiple traits

How can the environment influence genetic expression?

• By changing the DNA sequence

• By altering which genes are turned on or off

• By removing existing genes

• By creating new genes

What is an example of environmental influence on genetics?

• All twins having identical phenotypes regardless of environment

• Environmental factors creating new genes

• Genes being unaffected by external factors

• Identical twins having different phenotypes due to different environments

What is genetic recombination?

• The deletion of existing genes

• The exchange of genetic material between chromosomes during crossing over

• The creation of new genes

• The process of genes being passed on as a unit

Why is color blindness more common in males than females?

• Males have two X chromosomes

• Females have two Y chromosomes

• Males have only one X chromosome, which can carry the color blindness gene

• Females have only one X chromosome, which can carry the color blindness gene

Which chromosome is responsible for red-green color blindness?

• Chromosome 21

• X chromosome

• Chromosome 18

• Y chromosome