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Natural Selection - Workman 7th

Total questions: 12

Worksheet time: 10mins

Name
Class
Date
1.

A few years ago the population of male blue moon butterflies on the island of Samoa declined. One hypothesis for the decline of the male butterflies is that a parasite infected the cells of female butterflies. The parasite was passed to offspring through the females’ eggs and killed the male butterfly embryos. At one point during the decline, nearly all the butterflies in the population were females, but after five years the number of males in the population increased significantly.

Which explanation most likely accounts for the increase in the number of male butterflies in the five years after the initial parasite problem?

a)

Male butterflies in the population that survived were able to prey on the parasites living in the females’ egg cells.

b)

Female butterflies in the population that survived had a genetic adaptation that allowed them to transform into male butterflies.

c)

Male butterflies in the population that survived had a gene that made them resistant to the parasite, and they passed the gene on to their offspring.

d)

Female butterflies in the population that survived were able to protect the male eggs from the parasite and provide extra care for the male offspring.

2.

Several years of drought affect a population of plants in southwest Texas.  Which of the following characteristics would you expect to see more frequently in the plants over the next several generations?

Abundant broad leaves to capture more energy

Waxy coating on leaves to prevent water loss

Flowers blooming regularly to increase to seed production

Tall, narrow stems which are damage easily in high winds

a)

Abundant broad leaves to capture more energy

b)

Flowers blooming regularly to increase to seed production

c)

Waxy coating on leaves to prevent water loss

d)

Tall, narrow stems which are damage easily in high winds

3.

When Charles Darwin visited the Galapagos Islands in the 1800s, he observed many types of organisms that were similar but lived on different islands. The four species of mockingbirds found on the Galapagos Islands are shown below.  Each species lives on a different island.

These species are very similar, but the Hood mockingbird has a longer beak than the other three species. Which of the following best explains this difference?

a)

The Hood mockingbird needs a longer beak for defense against predators.

b)

The Hood mockingbird originated from a different type of bird than the other species.

c)

The Hood mockingbird’s longer beak is an adaptation to the food available in the bird’s habitat.

d)

The Hood mockingbird’s beak stretched to reach its food, and the longer beak was passed down to its offspring.

4.

Peppered moths often hide on white-colored birch trees because they are similarly colored. Which of the following environmental changes would lead to the enhanced survival of darker moths?

a)

Warm weather causes the birch trees to grow their leaves back early.

b)

Birch trees become covered in black ash from nearby factories.

c)

Heavy rainfall causes birch trees to grow taller than normal.

d)

Disease kills off more than half of the birch tree population.

5.

Mountain lions are large cats and the top predator in their habitat. The population of mountain lions may vary in several characteristics. If prey becomes more scarce, which variation would provide an advantage to the individuals that possessed it?

a)

A spotted coat

b)

Short fur

c)

Long Legs

d)

Abundant whiskers

6.

Leopard seals are animals adapted to survive in the freezing conditions of Antarctica. Individual leopard seals vary in their different traits. Which of the following variations would give a leopard seal the greatest chance of surviving in its harsh environment?

a)

More spots on its coat

b)

Thicker layer of blubber

c)

More elongated head

d)

Wider, flatter teeth

7.

Xylem is a plant tissue made up of elongated cells stacked end to end the length of the plant’s stem. Which function is xylem specifically adapted to perform in plants?

a)

Help prevent water loss

b)

Capture sunlight for photosynthesis

c)

Exchange gasses with the atmosphere

d)

Transport water from roots to leaves

8.

In a population of desert plants, the timing of their blooming varies greatly. Some bloom early in the morning, others at mid-day, and others after dark. What factor might be an advantage for the plants that bloom after dark?

a)

There is a decrease in water for root absorption.

b)

There is an increase in herbivores that forage at night.

c)

There is a decrease in the strength of solar radiation.

d)

There is an increase in the population of nocturnal pollinators.

9.

A trait that helps an organism survive and reproduce

a)

Adaptation

b)

Variation

c)

Allele

d)

Species

10.

The theory of natural selection was introduced by

a)

Gregor Mendel

b)

Sir Isaac Newton

c)

Charles Darwin

d)

Copernicus

11.

The hollow bones of birds, which keep birds lightweight for flying, is an example of ________

a)

Inheritance

b)

Adaptation

c)

Cool Bird stuff

d)

Variation

12.

Lake Victoria in East Africa is home to many species of fish called cichlids. In 1954 the predatory Nile perch was introduced to Lake Victoria. The Nile perch became the dominant fish species in the lake by the mid-1980s. The number of cichlid species in the lake decreased as the Nile perch population increased. The perch preyed heavily on cichlid species that fed on algae and debris on the bottom of the lake. Algae in the lake increased, and oxygen levels decreased. The surface area of the gills of some cichlid species has increased in just over 20 years.

Which statement explains the increase in gill surface area seen in some of Lake Victoria’s cichlids?

a)

Increased gill surface area has allowed the cichlids to change their diet and avoid competing with the Nile perch.

b)

Increased gill surface area has allowed the cichlids to leave Lake Victoria and establish populations in nearby bodies of water.

c)

Increased gill surface area has allowed the cichlids to be camouflaged and avoid being eaten by the Nile perch.

d)

Increased gill surface area has allowed the cichlids to better absorb the limited oxygen in the water.