Identification - Dichotomous Keys - Quiz, Flashcards & Trivia

1. An illustration of an organism and a dichotomous key are given. What is the organism?

Arachnid

Dragonfly

Fruit fly

May fly

Based on the given information, the organism depicted in the illustration is a dragonfly.

Explanation

Based on the given information, the organism depicted in the illustration is a dragonfly.

2. A dichotomous key is provided. A fish is caught that has eyes on the side of its head and a wide body covered in spots. What kind of fish is this?

Cornetfish

Flounder

Puffer fish

Snapper

The fish described in the question has eyes on the side of its head and a wide body covered in spots. Among the given options, the puffer fish is the most likely choice because puffer fish typically have eyes on the side of their head and their bodies are often wide and covered in spots. Therefore, the fish caught is most likely a puffer fish.

Explanation

The fish described in the question has eyes on the side of its head and a wide body covered in spots. Among the given options, the puffer fish is the most likely choice because puffer fish typically have eyes on the side of their head and their bodies are often wide and covered in spots. Therefore, the fish caught is most likely a puffer fish.

3. A scientist discovers a new plant in the jungle. Which of the following observations of the plants characteristics would be useful in determining its identity with a dichotomous key?

It was discovered in the summertime

It is wet from a recent rain storm

Its leaves curl up on the edges

It is eaten by native jungle ants

The observation that the plant's leaves curl up on the edges would be useful in determining its identity with a dichotomous key because this characteristic can help differentiate it from other plants. The dichotomous key is a tool that uses a series of choices to identify an organism based on its characteristics. By noting that the plant's leaves curl up on the edges, the scientist can use this as a distinguishing feature to narrow down the options in the dichotomous key and determine the plant's identity.

Explanation

The observation that the plant's leaves curl up on the edges would be useful in determining its identity with a dichotomous key because this characteristic can help differentiate it from other plants. The dichotomous key is a tool that uses a series of choices to identify an organism based on its characteristics. By noting that the plant's leaves curl up on the edges, the scientist can use this as a distinguishing feature to narrow down the options in the dichotomous key and determine the plant's identity.

4. An illustration of two fish is provided. Which paired statements could be used to know the difference between the fish using a dichotomous key?

Eyes on side of head. Eyes on top of head.

One set of dorsal fins. Two sets of dorsal fins

Mouth at front of head. Mouth on underside of head.

Rounded caudal fin. Forked caudal fin.

The correct answer is "Rounded caudal fin. Forked caudal fin." This is because a dichotomous key is a tool used to identify organisms based on a series of paired statements. In this case, the statements refer to different characteristics of the fish. The first statement "Rounded caudal fin" describes a fish with a rounded tail fin, while the second statement "Forked caudal fin" describes a fish with a tail fin that is divided into two lobes. By comparing these two statements, one can determine the difference between fish with rounded caudal fins and those with forked caudal fins.

Explanation

The correct answer is "Rounded caudal fin. Forked caudal fin." This is because a dichotomous key is a tool used to identify organisms based on a series of paired statements. In this case, the statements refer to different characteristics of the fish. The first statement "Rounded caudal fin" describes a fish with a rounded tail fin, while the second statement "Forked caudal fin" describes a fish with a tail fin that is divided into two lobes. By comparing these two statements, one can determine the difference between fish with rounded caudal fins and those with forked caudal fins.

5. An illustration of four leaves and a dichotomous key are provided. Use the dichotomous key to identify which of the leaves is from the magnolia tree.

Leaf 1

Leaf 2

Leaf 3

Leaf 4

6. A table of arachnid and insect characteristics is shown. Which characteristic could be used to distinguish between arachnids and insects?

Jointed legs

Body segments

Presence of eyes

Presence of antennae

The presence of antennae could be used to distinguish between arachnids and insects. Arachnids, such as spiders, scorpions, and ticks, do not have antennae, while insects, such as beetles, flies, and bees, typically have antennae. Therefore, the presence or absence of antennae can be a key characteristic in differentiating between these two groups of organisms.

Explanation

The presence of antennae could be used to distinguish between arachnids and insects. Arachnids, such as spiders, scorpions, and ticks, do not have antennae, while insects, such as beetles, flies, and bees, typically have antennae. Therefore, the presence or absence of antennae can be a key characteristic in differentiating between these two groups of organisms.

7. An illustration of three beetles is given. A student examines three different species of beetles that are related. What structure is identical in all three beetle species?

Antennae length

Placement of eyes

Markings on abdomen

Width of thorax

In the given illustration, the width of the thorax is the structure that is identical in all three beetle species. This means that regardless of the species, all three beetles have the same width of the thorax.

Explanation

In the given illustration, the width of the thorax is the structure that is identical in all three beetle species. This means that regardless of the species, all three beetles have the same width of the thorax.