Explaining Variation in Running Ability

Explaining Variation in Running Ability

Middle School

​

Learning Objectives

• Define the difference between inherited and acquired traits.

• Compare and contrast the processes of sexual and asexual reproduction.

• Explain how genes contribute to the variation of traits in a population.

• Use evidence to make a claim about how traits are passed from parents to offspring.

Key Vocabulary

​

Trait

A specific characteristic of an organism, like its eye color or its overall height.

​

Heredity

The passing of genetic traits from parents to their offspring through biological inheritance processes.

​

Gene

A basic unit of heredity that is transferred from a parent to its offspring.

​

Reproduction

The biological process by which new individual organisms, also known as offspring, are produced.

​

Asexual Reproduction

A type of reproduction that involves only one single parent organism to create offspring.

​

Sexual Reproduction

A type of reproduction that involves two different parent organisms to create a new organism.

Key Vocabulary

​

Variation

The differences in traits between individuals of the same exact species.

​

Claim

A statement that answers a question, supported by strong scientific evidence.

​

Evidence

Scientific data or facts that support a claim made about something.

Inherited vs. Acquired Traits

• Inherited traits are passed down from your parents through genes.

• Acquired traits are developed during your lifetime.

• Inherited traits can be passed on, but acquired traits cannot.

Multiple Choice

What is the primary distinction between an inherited trait and an acquired trait?

• Inherited traits are passed down from parents, while acquired traits are developed during a lifetime.

• Inherited traits are learned behaviors, while acquired traits are physical features.

• Inherited traits only come from one parent, while acquired traits come from both.

• Inherited traits can be changed, while acquired traits are permanent.

Multiple Choice

Which of these is an example of an acquired trait?

• A person having blue eyes.

• A person having naturally curly hair.

• A person's blood type.

• A person learning to speak Spanish.

Multiple Choice

A father with naturally brown hair dyes his hair black. If he has a child, what can be concluded about the hair color the child might inherit from him?

• The baby will definitely be born with the same dyed hair color.

• The father's dyed hair color cannot be passed on to the baby.

• The baby has a 50% chance of inheriting the dyed hair color.

• The baby will be born with a blend of the natural and dyed hair colors.

​

​

Asexual vs. Sexual Reproduction

Asexual Reproduction

• This type of reproduction involves only one parent.

• Offspring are genetically identical clones of the parent.

• It allows for rapid population growth in stable environments.

Sexual Reproduction

• This type of reproduction involves two different parents.

• Offspring inherit a unique mix of genes from both parents.

• Genetic variation helps species adapt to changing environments.

Multiple Choice

What is the main difference between asexual and sexual reproduction?

• The number of parents involved in the process.

• The environment where the offspring will live.

• The amount of time it takes for offspring to grow.

• The size of the offspring when they are born.

Multiple Choice

How does the genetic makeup of offspring from asexual reproduction compare to those from sexual reproduction?

• Offspring from asexual reproduction are clones, while offspring from sexual reproduction are genetically unique.

• Offspring from sexual reproduction are clones, while offspring from asexual reproduction are genetically unique.

• Offspring from both processes are genetically identical to their parents.

• Offspring from both processes have a unique mix of genes from their parents.

Multiple Choice

If a stable environment suddenly undergoes a major change, which type of reproduction would offer a species a better chance of long-term survival and why?

• Asexual reproduction, because it allows a population to grow very rapidly.

• Sexual reproduction, because it always produces stronger offspring.

• Asexual reproduction, because all offspring are guaranteed to be identical to the successful parent.

• Sexual reproduction, because genetic variation increases the chance that some offspring can adapt.

​

​

Genes and Variation

What Are Genes?

• Genes are small segments of DNA that provide instructions for an organism's specific traits.

• An offspring inherits a combination of genes from both parents during sexual reproduction.

• This genetic mix is why siblings can look very different from each other.

What Is Variation?

• The recombination of genes during reproduction is what leads to genetic variation.

• Variation describes the differences we can see among individuals, like height or eye color.

• This diversity helps a species adapt to and survive changes in their environment.

Multiple Choice

What are genes?

• Small segments of DNA that provide instructions for an organism's specific traits.

• The building blocks of an organism's cells.

• The part of the body that pumps blood.

• A type of nutrient an organism gets from food.

Multiple Choice

What is the main reason that siblings from the same parents can look very different from each other?

• Because they eat different types of food.

• Because they are always different ages.

• Because they inherit a different combination of genes from their parents.

• Because one parent provides all the genetic instructions.

Multiple Choice

If a species' environment changes, what is the most significant advantage of having genetic variation?

• It guarantees that all individuals in a species will be identical.

• It prevents a species from changing over time.

• It increases the chance that some individuals will have traits needed to survive the changes.

• It reduces the number of genes passed on to the next generation.

​

Common Misconceptions

Misconception	Correction
All traits are determined by genes.	Many traits are acquired through environment or an individual's actions.
Offspring inherit traits in a perfect 50/50 blend from their parents.	The combination of genes is unique, and some are dominant.
Asexual reproduction is a less successful method than sexual reproduction.	It is highly effective and rapid in stable environments.

​

Summary

• Traits are inherited through genes or acquired from the environment.

• Asexual reproduction from one parent creates genetically identical offspring.

• Sexual reproduction from two parents creates genetically unique offspring.

• Mixing genes during sexual reproduction causes variation within a species.

• Genetic variation helps species adapt to changing environments.

• Scientists use evidence and data to support claims about heredity.

Poll

On a scale of 1-4, how confident are you about explaining the difference between an inherited and an acquired trait?

• 1

• 2

• 3

• 4