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1 Inheritance and Variation of Traits Take a moment to think about the child shown in the picture on the right. His name is Juan. What are some things you can say about Juan by looking at the picture? He has brown hair. His hair is straight. His eyes are also brown. He has ten fingers. These characteristics are called inherited traits. Most physical traits are inherited, but some are not. For example, many people change their hair color with dye. These people do not pass the new hair color onto their children. Suppose a deer has a broken antler. This physical trait will not get passed on to the deer’s offspring. reproduction making more of the same kind of living thing physical of the body offspring – the child or offshoot of a parent Juan has other characteristics you cannot see by looking at the picture. Maybe he knows how to swing by himself. Perhaps he can ride a bike or play an instrument. These characteristics are called learned behaviors. Juan learned how to do these things; they were not inherited. What does inherited mean? If something is inherited, it means it was passed on from a parent to an offspring. A trait is an internal or external characteristic. So inherited traits are characteristics that are passed from parent to offspring. This passing of traits happens during reproduction. The baby alligator looks a lot like its parents. The baby alligator’s traits are inherited.

Inheritance and Variation of Traits · Traits can be inherited by the offspring of both plants and animals. The color of a flower is a trait passed from parents to offspring. Eye

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Page 1: Inheritance and Variation of Traits · Traits can be inherited by the offspring of both plants and animals. The color of a flower is a trait passed from parents to offspring. Eye

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Inheritance and Variation of Traits

Take a moment to think about the child shown in the picture on the right. His name is Juan. What are some things you can say about Juan by looking at the picture? He has brown hair. His hair is straight. His eyes are also brown. He has ten fingers. These characteristics are called inherited traits.

Most physical traits are inherited, but some are not. For example, many people change their hair color with dye. These people do not pass the new hair color onto their children. Suppose a deer has a broken antler. This physical trait will not get passed on to the deer’s offspring.

reproduction – making more of the same kind of living thing

physical – of the body

offspring – the child or offshoot of a parent

Juan has other characteristics you cannot see by looking at the picture. Maybe he knows how to swing by himself. Perhaps he can ride a bike or play an instrument. These characteristics are called learned behaviors. Juan learned how to do these things; they were not inherited.

What does inherited mean?If something is inherited, it means it was passed on from a parent to an offspring. A trait is an internal or external characteristic. So inherited traits are characteristics that are passed from parent to offspring. This passing of traits happens during reproduction.The baby alligator looks a lot like

its parents. The baby alligator’s traits are inherited.

Page 2: Inheritance and Variation of Traits · Traits can be inherited by the offspring of both plants and animals. The color of a flower is a trait passed from parents to offspring. Eye

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What are variations?

Look at the tulips above. Are they exactly the same color? What about the foal and its parent? Is their fur exactly the same color? They look a little different! This happens because groups of organisms have variations.

Variations are differences in traits that can be found in groups of plants and animals.

Look at the kittens to the left. Do they all look alike? Do they look like their mother? These kittens have the same parents, but they look a little different from each other. Each kitten inherited different traits from their parents. This causes variations between groups of the same kind of animal.

What characteristics of animals and plants are inherited?

Traits can be inherited by the offspring of both plants and animals. The color of a flower is a trait passed from parents to offspring. Eye color and fur color can be passed on, too. The size and shape of a body are also traits passed from parents to offspring. Other inherited traits include characteristics such as fins on a fish or stripes on a tiger. A plant can inherit the shape of its flower, the number and pattern of its petals, and the size of its leaves.

The young foal inherited the white stripe on its face from its parent.

The tulips inherited their petal shape and color from their parents.

Inheritance and Variation of Traits

Page 3: Inheritance and Variation of Traits · Traits can be inherited by the offspring of both plants and animals. The color of a flower is a trait passed from parents to offspring. Eye

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Plant Inheritance and Variation

Plants also inherit traits from their parent plants. The shape of the leaves, the texture of the stem, the number of petals, and the color of the flower are all inherited traits.

Baby plants, such as these three lima bean plants, grow from seeds produced by a parent plant.

The three baby plants have inherited leaves shaped like the parent plant.

When the lima bean plants are fully grown, they will produce more seeds that can grow more baby plants.

The plants can have variations, too. There may be a difference in how tall they grow or how many seeds they produce.

Lima bean plants

Lima bean seeds

Lima bean seedlings

Use the words below to complete each sentence.

● Something you observe about an organism (the way it looks or acts) is called a ________________________________________________________________

● Differences in traits, such as petal color or fur pattern, are called ________________________________________________________________

● Tiger offspring resemble their parents in having four legs and stripes. Resemble means their traits are the ___________________________________________.

● A litter of puppies do not always have exactly the same fur color. This means their traits are____________________________________________________.

● Offspring get traits such as height and petal shape from their _______________________________________________________________.

Word Bank

different, variations, trait, same, parents

Inheritance and Variation of Traits