3rd Grade Science : Life Science

Study concepts, example questions & explanations for 3rd Grade Science

varsity tutors app store varsity tutors android store

Example Questions

Example Question #1 : Explain How Animals May Change Due To Environmental Changes

Birds that are migrating to California usually stop along the way to rest, eat, and drink water. The birds head to California to get away from the frigid weather in Canada. They would not survive without migrating. This year as the birds land at their usual stopping points, they notice it is hotter and dryer than average. As humans, we realize we are in a drought, but the birds do not know this. They are struggling to make the rest of the journey because it is too hot, and there is no water to drink.

What will most likely happen to the birds because of the severe drought?

Possible Answers:

They will dig deep into the ground to find water sources.

They will not make the journey and they will die.

They will have to turn around and go home.

There is no way to predict what will happen to the birds.

Correct answer:

They will not make the journey and they will die.

Explanation:

The birds are facing more than one problem caused by the environment in this scenario. They have to get to California to stay out of the cold weather in Canada, but there is nowhere to rest with food and water on their current route. The birds will likely not make the journey and die if they do not have access to water. It is improbable that the birds will make the trip back home due to exhaustion, and they cannot dig into the ground for water sources.

Example Question #12 : Environmental Changes That Cause Problems

What is a positive effect that an environmental change may have on an animal?

Possible Answers:

Jacey got a new puppy for a pet, and he loves fetching sticks in the yard.

Jackson's Boy Scout troop installed new bat houses in the local park.

A baby bird fell out of its nest and is now separated from its family.

Spiders are nocturnal and hunt at night, so I set up large lights in my yard for them.

Correct answer:

Jackson's Boy Scout troop installed new bat houses in the local park.

Explanation:

Animals can suffer adverse consequences that require them to change their behavior to survive, but there are also positive effects of environmental changes. "Jackson's Boy Scout troop installed new bat houses in the local park" is the correct answer because this adds shelter for bats, which is positive, and it will bring more bats to the area to eat pesky insects.

Example Question #151 : 3rd Grade Science

Which answer choice is an example of a change that an animal would be able to make due to the environment changing?

Possible Answers:

All birds move to Texas because the weather is pleasant year-round.

Alligators move to saltwater pools because there are better fish.

A cat hides under a car to stay dry when caught in a rainstorm.

Bat's improve their eyesight so they can see more insects as some species start to disappear.

Correct answer:

A cat hides under a car to stay dry when caught in a rainstorm.

Explanation:

Animals often have to change their behaviors to adapt to changes in the environment. Cats would be able to hide under cars to escape a thunderstorm and stay dry. This is a change that they would be able to do. The other answer choices are improbably or impossible for animals to do.

Example Question #14 : Environmental Changes That Cause Problems

Polar bears hunt seals through holes in the sea ice. They travel from great distances across sheets of frozen water to find seal colonies. The seals rest on the ice in large groups and raise their pups. When the seals go out to hunt fish they slip into the water from the edge of the ice.

If temperatures rise and the ice begins to melt, what impact could there be for the seals?

Possible Answers:

Melting sea ice and warmer temperatures means the seals will become better swimmers.

The temperature warming and ice melting would mean more summer fun for seals.

Warmer temperatures and melting sea ice would not impact seals.

Seals would not have places to raise their pups and would be exposed to bears.

Correct answer:

Seals would not have places to raise their pups and would be exposed to bears.

Explanation:

Animals may have to change when there are environmental changes that impact their lives. In the case of the seal dealing with the difference in the amount of sea ice, the change would need to be huge to survive. Seals rely on the sea ice for raising their pups and escaping polar bears, so they would either need to adapt and change their offspring-rearing techniques or find another place to live. These changes would be challenging, and the seals may not survive.

Example Question #1 : Explain How Trait Variations Give Reproduction Advantages

Pollinators prefer plants that have strong smells and brightly colored flower petals when they are selecting a place to collect nectar. Which plant is LEAST likely to attract a pollinator?

Possible Answers:

Flower, Peony, Ornamental Plant, Spring

Flower, Clover, Nature, Plant, Spring

Finger Shrub, Nordic Figer Shrub

Honeysuckle, Nature, Spring, Outdoor

Correct answer:

Finger Shrub, Nordic Figer Shrub

Explanation:

The plant that is least likely to attract a pollinator would be the shrub. It is only green, has no flowers, and has no nectar to attract a pollinator. When a bee, bat, butterfly, etc. lands on the flower and moves to collect the nectar, pollen is transferred onto the animal's body, and then cross-pollination happens when it lands on another flower. The other photos show very brightly colored flowers that would catch the eye of a passing pollinator.

Example Question #2 : Explain How Trait Variations Give Reproduction Advantages

Trait variations give reproductive advantages to some plants and animals.

Possible Answers:

True

False

Correct answer:

True

Explanation:

The statement is true. When traits change or carry, there are benefits or advantages to the process. If a feature is a strength and helps animals to survive, they will be more likely selected as a mate, live longer, and produce healthier offspring. These offspring will carry the adapted characteristics with them and pass them on to their offspring, which in turn makes the family group and species stronger.

Example Question #3 : Explain How Trait Variations Give Reproduction Advantages

A population of dark-colored moths moves into an area with light-colored moths. The area has lots of birch trees. The dark-moths stand out against the white and grey trees. More dark moths are eaten by predators than light moths. Only moths that live to reproduction age will produce offspring.

Which moth or moths has the advantage because of their traits to get the change of reproducing?

Trees, Birch, White, Trunk, Forest

Possible Answers:

Both moths; The light and dark moths will both have an equal chance of reproducing, and neither has an advantage over the other.

Neither; The light-colored and dark-colored moths have no advantage of getting to reproduce, and neither will reach the age of mating.

Dark-colored moth; This moth has a better chance of reproducing because more of them will survive to the age of mating.

Light-colored moth; This moth has a better chance of reproducing because more of them will survive to the age of mating.

Correct answer:

Light-colored moth; This moth has a better chance of reproducing because more of them will survive to the age of mating.

Explanation:

In this scenario, the lighter-colored moth has a better chance at survival because it blends in with the beige and white birch trees. The more moths that survive, the more can reach adulthood and create offspring. The dark-colored moths are more likely to stand out against the white and beige trees, so there are less that will survive to reproduce.

Example Question #144 : Life Science

In the cold tundras, ice and snow cover the ground for most of the year. Animals have to have strong traits to survive long enough to find a mate and reproduce. Female animals only want the strongest males with the best characteristics to pass on to their offspring.

Which animal would be more likely to live long enough to reproduce in this type of environment?

Possible Answers:

Snake, Green, Macro, Animal, Zoo

Fox, Arctic, White, Winter, Cold

Ara, Parrot, Yellow Macaw, Bird, Animal

Morpho, Polyphemus, Butterfly, White

Correct answer:

Fox, Arctic, White, Winter, Cold

Explanation:

The animal that would be most likely to live long enough in the cold tundra would be an arctic fox. This animal has thick fur, a layer of fat, white fur to blend with the snow, and even changes its fur color to brown in the summer months when there is no snow. This animal is suited to this environment. The snake, moth, and parrot all are perfect for their environments but would not live to reproduce in the tundra and would not have the right traits to pass on for offspring to survive either.

Example Question #4 : Explain How Trait Variations Give Reproduction Advantages

Pollinators prefer plants that have strong smells and brightly colored flower petals when they are selecting a place to collect nectar like the one pictured below. How does this variation in appearance give them an advantage in reproducing?

Forget Me Not, Hoverfly, Fly, Bloom

Possible Answers:

Attracting more pollinators gives the plant a lesser chance of spreading pollen.

There is no advantage in reproduction because of flower color or smell.

Attracting fewer pollinators gives the plant a higher chance of spreading pollen.

Attracting more pollinators gives the plant a higher chance of spreading pollen.

Correct answer:

Attracting more pollinators gives the plant a higher chance of spreading pollen.

Explanation:

When a bee, bat, butterfly, etc. lands on the flower and moves to collect the nectar, pollen is transferred onto the animal's body, and then cross-pollination happens when it lands on another flower. The photo shows very brightly colored flowers that would catch the eye of a passing pollinator. Flowers that are brightly colored and have strong odors are more likely to attract pollinators, which give them an advantage in reproduction. If more pollinators are landing on their petals and spreading their pollen, they have a better chance of creating new plants.

Example Question #2 : Explain How Trait Variations Give Reproduction Advantages

Trait variations give reproductive advantages to animals but not plants. Plants do not reproduce.

Possible Answers:

False

True

Correct answer:

False

Explanation:

The statement in the question is false. When traits change or carry, there are benefits or advantages to the process. If a feature is a strength and helps animals to survive, they will be more likely selected as a mate, live longer, and produce healthier offspring. These offspring will carry the adapted characteristics with them and pass them on to their offspring, which in turn makes the family group and species stronger. Plants reproduce by spreading pollen from plant to plant (carried by pollinators), and seeds are formed. These seeds grow into new plants, and the most reliable genes survive and carry on the species.

Learning Tools by Varsity Tutors