1.
What is the likely ancestor of arthropods?
Correct Answer
A. Annelids
Explanation
The likely ancestor of arthropods is annelids. Arthropods and annelids share several similarities, such as segmented bodies and jointed appendages. Additionally, both groups belong to the larger category of protostomes, which are characterized by having a mouth that develops from the first opening in the embryo. Echinoderms, on the other hand, are a completely different group of animals that lack the segmented body plan and jointed appendages seen in arthropods. Therefore, annelids are the most likely ancestor of arthropods based on these similarities and evolutionary relationships.
2.
What is a mandibulate?
Correct Answer
B. An arthropod with a jaw
Explanation
A mandibulate is an arthropod with a jaw. Arthropods are a large group of invertebrate animals that include insects, spiders, and crustaceans. The mandibles are the jaws of these arthropods, which they use for biting and chewing. This feature sets them apart from other organisms, such as echinoderms, which do not have jaws. Therefore, the correct answer is "an arthropod with a jaw."
3.
What is a chelicerate?
Correct Answer
A. An arthropod with fangs or pincers
Explanation
A chelicerate is an arthropod with fangs or pincers. Chelicerates are a subphylum of arthropods that include spiders, scorpions, ticks, and horseshoe crabs. They are characterized by their specialized mouthparts called chelicerae, which are used for feeding and defense. These fangs or pincers are typically located at the front of their bodies and are used to grasp and immobilize prey or inject venom. Chelicerates also have a body divided into two main parts, the cephalothorax and the abdomen, and lack a distinct head region.
4.
A compound eye is made of thousands of individual units called:
Correct Answer
C. Ommatidia
Explanation
A compound eye is a type of eye found in insects and crustaceans, made up of thousands of individual units called ommatidia. Each ommatidium contains a lens, a light-sensitive receptor cell, and nerve fibers. These ommatidia work together to create a mosaic image, allowing the insect to detect movement and perceive their surroundings. The other options, spiracles, corneas, and retinas, are not correct because they do not refer to the individual units that make up a compound eye.
5.
Arthropods shed and discard their exoskeletons periodically as they grow in a process called molting or
Correct Answer
A. Ecdysis
Explanation
Arthropods, such as insects and crustaceans, undergo a process called molting or ecdysis. This involves shedding and discarding their old exoskeletons periodically as they grow. This allows them to accommodate their increasing size and replace damaged or worn-out exoskeletons. Ecdysis is essential for arthropods to continue growing and developing throughout their lives. It is a characteristic feature of this group of animals and plays a crucial role in their life cycle and survival.
6.
Molting is signaled by:
Correct Answer
B. Hormones
Explanation
Molting, the process of shedding old skin, feathers, or exoskeleton, is primarily regulated by hormones in animals. Hormones such as ecdysone and juvenile hormone play a crucial role in initiating and controlling the molting process. These hormones are responsible for signaling the growth and development of new skin or body covering. Proteins, carbohydrates, and electrical impulses do not have a direct role in signaling or regulating the molting process.
7.
Arthropod are traditionally grouped into 4 seperate subphyla.
Correct Answer
B. False
Explanation
they are traditionally grouped into 3 seperate subphyla
8.
The three subphyla of arthropods are:
Correct Answer
B. Uniramia, crustacea, and chelicerata
Explanation
The correct answer is "uniramia, crustacea, and chelicerata." These three subphyla are the commonly recognized subphyla of arthropods. Uniramia includes insects and myriapods, crustacea includes crabs, lobsters, and shrimp, and chelicerata includes spiders, scorpions, and horseshoe crabs. This classification is based on the presence or absence of certain characteristics and the evolutionary relationships between these groups of arthropods.
9.
Arachnids have a pair of chelicerae as their foremost appendage.
Correct Answer
A. True
Explanation
Arachnids, such as spiders, scorpions, and ticks, indeed have a pair of chelicerae as their foremost appendage. Chelicerae are specialized mouthparts that are used for feeding and defense. They are located in front of the arachnid's mouth and are typically equipped with fangs or pincers, which they use to capture and immobilize their prey. Therefore, the statement that arachnids have a pair of chelicerae as their foremost appendage is true.
10.
All arachnids, except spiders are carnivores.
Correct Answer
B. False
Explanation
all arachnids except mites are carnivores
11.
What is the name of the second pair of appendages (in arachnids) that are used to catch and handle prey--they are sometimes specialized for sensory or even reproductive functions.
Correct Answer
A. Palps
Explanation
Arachnids have a pair of appendages called palps that are used to catch and handle prey. These palps can also be specialized for sensory or reproductive functions. They are not used for jumping or spinning webs like jumping legs and spinnerets respectively. Forelegs are also not the correct answer as they are not specifically used for catching and handling prey.
12.
Scorpions are arachnids whose palps have evolved into large, grasping.
Correct Answer
pincers
Explanation
Scorpions are a type of arachnid that have evolved large, grasping pincers from their palps. These pincers are used for capturing and immobilizing prey, as well as for defense. The evolution of these pincers has allowed scorpions to become highly efficient predators, as they are able to hold onto their prey firmly and deliver a venomous sting. The development of pincers has been a significant adaptation for scorpions, enabling them to survive and thrive in their diverse habitats.
13.
Spiders:
Correct Answer(s)
A. Have poison glands that secrete toxin through chelicerae that have been modified into fangs
C. Eight legs
D. Web spinning abilities
Explanation
Spiders have poison glands that secrete toxin through chelicerae that have been modified into fangs. This is a characteristic feature of spiders, as their venom is used to immobilize or kill their prey. Additionally, spiders have eight legs, which is another distinguishing feature of this arachnid group. Furthermore, spiders possess web spinning abilities, which they use to construct intricate webs for capturing prey or creating shelters. These three traits collectively define the unique characteristics of spiders.