Selective Breeding and Genetic Variation Quiz

Match the following processes with their descriptions.

• Genetic engineering

• A spontaneous mutation leading to genetic disorders

• Evolution

• A method of genetic engineering to insert genes into a genome

• Genetic mutation

• A natural process where organisms evolve over time

• Selective breeding

• An artificial process where humans breed plants and animals for specific traits

Answer explanation

Selective breeding is an artificial process where humans breed plants and animals to enhance specific traits, distinguishing it from natural evolution and genetic engineering methods.

Which characteristics is most relevant in selectively bred plants.

• Disease resistance in food crops

• Increased intelligence

• Ability to survive without water

• Ability to fly

• Important for ensuring crop yield and food security

Answer explanation

Disease resistance in food crops is a key goal in selective breeding, as it helps ensure higher yields and food security. The other options, such as increased intelligence or the ability to fly, are not applicable to plants.

A potential risk of selective breeding is (a)  

• Improved resistance to all diseases

• Reduced genetic variation
• Creation of new species

• Increased genetic variation

Answer explanation

Selective breeding can reduce genetic variation, making populations more susceptible to diseases. This lack of diversity limits the ability to adapt to new threats, increasing vulnerability.

Michael is explaining to his classmates that ___ is a benefit of selective breeding. Tick all that apply.

• Increased yield
• Disease resistance
• Faster growth

• Better taste

Answer explanation

Selective breeding leads to the development of new varieties that are economically important, enhancing agricultural productivity and providing crops or animals that meet market demands.

In a biology class, Benjamin and Zoe are learning about genetics. What is meant by 'gene pool'?

• A collection of all genes and their different alleles within a population

• A pool where genes are stored

• A method of genetic engineering

• A type of selective breeding

Answer explanation

The term 'gene pool' refers to the total collection of genes and their various alleles present within a population, making the first answer choice the correct one. The other options do not accurately describe this concept.

Match the following animal characteristics with their selective breeding purposes.

• Chickens bred for higher egg yield

• Ability to change color

• Dogs bred for guarding and protection

• Ability to live underwater

• Chameleons adapting to their environment

• Increased aggression

• Fish surviving in aquatic habitats

• Production of large eggs in chickens

Answer explanation

In selective breeding, traits that enhance productivity are prioritized. The production of large eggs in chickens is a key characteristic selected for, as it directly impacts egg yield and farming efficiency.

In a small farming community, what is a consequence of a reduced gene pool in their crops?

• Increased genetic variation

• Easier production of new varieties

• Increased biodiversity

• Organisms become more prone to diseases

Answer explanation

A reduced gene pool limits genetic diversity, making organisms more susceptible to diseases. This is because there are fewer genetic variations to provide resistance against pathogens.

Match the reasons for selectively breeding cows with the correct outcomes.

• Breeding disease-immune cows

• To create cows that are resistant to all diseases

• Developing aquatic cows

• To produce cows that can fly

• Enhancing meat and dairy quality

• To make cows that can survive in water

• Creating cows with wings

• To produce cows with highly desirable characteristics for meat and dairy

Answer explanation

Farmers selectively breed cows to enhance traits that are desirable for meat and dairy production, such as size, milk yield, and growth rate, ensuring better quality and efficiency in their livestock.

Abigail has a large dog that was selectively bred. What is a potential physical problem her dog might face?

• Ability to fly

• Faulty hips due to improper formation

• Resistance to all diseases

• Increased intelligence

Answer explanation

Selectively bred large dogs often suffer from faulty hips due to improper formation, a common genetic issue. This condition can lead to pain and mobility problems, making it a significant concern in these breeds.

Priya is working on a selective breeding project and is considering selecting genes associated with rare diseases. What is a risk of this approach?

• Improved health in all organisms

• Problems with specific organisms, such as deafness in Dalmatian dogs

• Creation of new species

• Increased genetic diversity

Answer explanation

Selecting rare disease genes can lead to specific health issues in certain breeds, such as the deafness seen in Dalmatian dogs. This highlights the risk of unintended consequences in selective breeding.