The male flying dragon lizard in the photo is opening a brightly-colored flap of skin at its throat. This is a display of courtship behavior that only happens during certain times of the year. ***What is the effect of this courtship behavior?***

Janna plans to give her teacher a plant she's grown from seed as an end of the year gift. After the seed sprouts, she places the pot next to a window. ***Which statement explains why the plant in the photo seems to be growing toward the light? ***

The photo shows plant seed pods that became stuck in a horse's mane as the horse grazed in a field. The hooked structure of these seed pods mean they can get caught on passing animals. As the horse trekked across several acres of land throughout the day, seed pods fell from its mane. Many of these seed pods landed in different fields. ***How does the structure of the seed pods affect the likelihood the plant will reproduce?***

A gardener does a simple experiment. She plants seeds from the same kind of flower in two garden boxes. She gives one group of seeds fertilizer and water. She gives the other group only water. The garden boxes get the same amount of light and are at the same temperature. ***The picture shows how the plants look after several weeks. Based on the evidence in the picture, which statement identifies the most likely explanation for the results of her experiment?***

Diego learns that male fireflies attract mates of their own species by flashing light from their abdomen in a specific pattern. He would like to investigate how female fireflies react to this male behavior. ***What type of device could Diego design and improve upon to use in his investigation?***

An organism must have physical traits in order to help it get and conserve water. What is one way in which a plant's physical traits help it prevent dehydration?

Members of the species of cicada, shown in the photo, live underground for most of their lives. However, every seventeen years, they come out of the ground to mate. After mating, each female lays about six hundred eggs in tree branches. Larvae hatch from these eggs, drop to the ground, and burrow into the soil. ***How do these cicadas increase the chances of the survival of their offspring?***

Aphids, shown in the photo, are pests for papaya plants. As the aphids drink a papaya plant juices, they infect the plant with a virus. Once infected by the virus, plants cannot grow healthy leaves. Papaya growers often spray oils on their plants to control aphids. ***Which describes a papaya plant that is more likely to die?***

Alfalfa plants produce a chemical that tastes bitter to certain types of insects. Which statement explains the effect of producing this chemical?

Yasmin enters an engineering competition to design a model of a seed meant to be dispersed by wind. The models will be judged based on two criteria: the model needs to stay in the air for at least 30 seconds and land on a target when dropped from 10 meters above the ground. Yasmin thinks about different designs for a couple of days. Then she builds the design she thinks will work best. The result of her first test is in the table. ***What should Yasmin do to win the competition?***

Male humpback whales make certain sounds to attract a mate. This behavior seems to be passed on from one generation to the next. ***Which of the following statements best describes an effect of these male whale songs?***

An engineer is asked to solve a problem with a passenger train in Japan. The train is able to carry a large number of passengers at high speeds. However, the train makes a lot of noise as it passes through neighborhoods where many people live and work. The noise it makes can be measured in decibels, reaching 90 decibels at its loudest. ***Which criterion is most likely to ensure the engineer comes up with a successful solution to the problem?***

Plants often need animals to disperse their seeds. Why then, do some of these plants produce very spicy pods that cover their seeds? Humans may enjoy the taste of spicy foods, but most other animals do not. Two scientists wanted to find out if the spicy substances produced by some pepper plants affect the plants’ ability to reproduce. They already knew that, after eating, mice leave behind broken seeds that cannot germinate, while birds leave behind whole seeds that can germinate. For the experiment, they offered each type of animal the same number of three foods: berries, non-spicy peppers, and spicy peppers. They recorded how much of each food was eaten. ***Based on the data table, for which food did the two animals differ the most in the amount they ate?***

Plants often need animals to disperse their seeds. Why then, do some of these plants produce very spicy pods that cover their seeds? Humans may enjoy the taste of spicy foods, but most other animals do not. Two scientists wanted to find out if the spicy substances produced by some pepper plants affect the plants’ ability to reproduce. They already knew that, after eating, mice leave behind broken seeds that cannot germinate, while birds leave behind whole seeds that can germinate. For the experiment, they offered each type of animal the same number of three foods: berries, non-spicy peppers, and spicy peppers. They recorded how much of each food was eaten. ***Which conclusion can be drawn from what you know about seed dispersal and from the evidence in the table?***

Plants often need animals to disperse their seeds. Why then, do some of these plants produce very spicy pods that cover their seeds? Humans may enjoy the taste of spicy foods, but most other animals do not. Two scientists wanted to find out if the spicy substances produced by some pepper plants affect the plants’ ability to reproduce. They already knew that, after eating, mice leave behind broken seeds that cannot germinate, while birds leave behind whole seeds that can germinate. For the experiment, they offered each type of animal the same number of three foods: berries, non-spicy peppers, and spicy peppers. They recorded how much of each food was eaten. ***Which evidence supports the argument that producing a spicy substance can help pepper plants reproduce?***

Many plants have traits to protect themselves from being eaten by animals. For example, certain types of plants have small hairs on their leaves. These hairs can prevent an insect's mouth parts from reaching the leaf material. A group of scientists wanted to see if there was a relationship between the density of the leaf hairs on plant leaves and how badly the leaves were damaged by insects. They collected leaves from five types of jimsonweed plants grown in the same environment, with the same amount of water, nutrients, and sunlight. They counted the number of hairs on a small area of each type of leaf, and calculated the average number of hairs per square millimeter. They then measured how much of the leaf was eaten after it was exposed to insects. They made a graph of the relationship between the two values. Each numbered point on the graph represents a different type of plant. ***Which statement about the density of leaf hairs is supported by the data in the graph?***

Many plants have traits to protect themselves from being eaten by animals. For example, certain types of plants have small hairs on their leaves. These hairs can prevent an insect's mouthparts from reaching the leaf material. A group of scientists wanted to see if there was a relationship between the density of the leaf hairs on plant leaves and how badly the leaves were damaged by insects. They collected leaves from five types of jimsonweed plants grown in the same environment, with the same amount of water, nutrients, and sunlight. They counted the number of hairs on a small area of each type of leaf, and calculated the average number of hairs per square millimeter. They then measured how much of the leaf was eaten after it was exposed to insects. They made a graph of the relationship between the two values. Each numbered point on the graph represents a different type of plant. ***Which explanation about the function of leaf hairs is supported by evidence from the graph ?***

Many plants have traits to protect themselves from being eaten by animals. For example, certain types of plants have small hairs on their leaves. These hairs can prevent an insect's mouth parts from reaching the leaf material. A group of scientists wanted to see if there was a relationship between the density of the leaf hairs on plant leaves and how badly the leaves were damaged by insects. They collected leaves from five types of jimsonweed plants grown in the same environment, with the same amount of water, nutrients, and sunlight. They counted the number of hairs on a small area of each type of leaf, and calculated the average number of hairs per square millimeter. They then measured how much of the leaf was eaten after it was exposed to insects. They made a graph of the relationship between the two values. Each numbered point on the graph represents a different type of plant. ***Which explanation about the differences in hair density in the five groups of jimsonweed is most likely?***