1.
Light-sensitive sense organs in the flatworms are called ______.
Correct Answer
B. Ocelli
Explanation
Ocelli are light-sensitive sense organs found in flatworms. These organs help flatworms detect changes in light intensity and direction, allowing them to respond to their environment. Ocelli are simple eyes that can detect the presence or absence of light, but they cannot form images like more complex eyes. Flatworms use their ocelli to navigate and find food sources, as well as to avoid predators. Therefore, ocelli are the correct answer for the light-sensitive sense organs in flatworms.
2.
The human liver fluke, Clonorchis sinensis, is common in China, and can cause cirrhosis of the liver and death.
Correct Answer
A. True
Explanation
The statement is true because Clonorchis sinensis, also known as the human liver fluke, is indeed common in China. This parasitic worm infects the liver and can cause various health problems, including cirrhosis of the liver. If left untreated, it can lead to severe complications and even death.
3.
Members in the Phylum Nematoda possess a pair of lateral sensory organs called _______.
Correct Answer
amphids
amphid
Explanation
Members in the Phylum Nematoda possess a pair of lateral sensory organs called amphids. Amphids are specialized chemosensory organs that are located on the head of nematodes. They play a crucial role in detecting chemicals in the environment and are involved in various sensory functions such as finding food, mates, and avoiding predators. These sensory organs are important adaptations that enable nematodes to survive and thrive in their habitats.
4.
Which is NOT TRUE about the cuticle functions in nematodes?
Correct Answer
A. As a hook to burrow into muscle tissue forming cysts for parasitic nematodes.
Explanation
The cuticle functions in nematodes include acting as a barrier and providing protection, serving as a sensory array to detect changes in the environment, and functioning as a hydrostatic skeleton to aid in locomotion. However, it is not true that the cuticle acts as a hook to burrow into muscle tissue and form cysts for parasitic nematodes.
5.
Sexually, earthworms are _____________.
Correct Answer
B. HermapHroditic but not self-fertilizing
Explanation
Earthworms are hermaphroditic, meaning they have both male and female reproductive organs. However, they are not self-fertilizing, which means they cannot fertilize their own eggs with their own sperm. Instead, earthworms must mate with another earthworm in order to reproduce.
6.
Ctenophores possess eight comb rows composed of long, fused ______.
Correct Answer
cilia
Explanation
Ctenophores, also known as comb jellies, have eight comb rows that are made up of long, fused cilia. Cilia are hair-like structures that are found on the surface of many organisms and are involved in various functions such as locomotion and feeding. In the case of ctenophores, the cilia in their comb rows beat in a coordinated manner, creating a beautiful shimmering effect and allowing them to move through the water. The fusion of the cilia in each comb row gives them a stronger and more efficient beating motion, enabling ctenophores to swim and capture their prey effectively.
7.
Ctenophores do not possess nematocysts, instead they have adhesive prey capturing cells called _________.
Correct Answer
colloblasts
Explanation
Ctenophores, also known as comb jellies, do not possess nematocysts (stinging cells) like cnidarians. Instead, they have specialized adhesive cells called colloblasts. Colloblasts are used to capture prey by releasing a sticky substance that helps adhere to and immobilize their prey.
8.
In Ctenophores, what are used for locomotion?
Correct Answer
B. Costae
Explanation
In ctenophores, also known as comb jellies, locomotion is achieved through rows of ciliary plates called costae. These costae beat in a coordinated manner, propelling the ctenophore through the water. This unique method of locomotion distinguishes ctenophores from other marine organisms.
9.
The free-living platyhelminths are usually considered the most primitive bilateral animals and the 1st group to have evolved a true ______________.
Correct Answer
mesoderm
Explanation
Free-living platyhelminths, or flatworms, are considered the most primitive bilateral animals and are significant for being the first group to have evolved a true mesoderm. The mesoderm is the middle layer of cells in the developing embryo, giving rise to muscles, the circulatory system, and other internal structures, enabling greater complexity and functionality in the animal's body plan.
10.
Flatworm osmoregulation is through a specialized organ called __________.
Correct Answer
D. ProtonepHridia
Explanation
Flatworms use a specialized organ called protonephridia for osmoregulation. Protonephridia are networks of tubules with flame cells that help regulate the balance of water and salts within the flatworm's body, enabling them to maintain homeostasis in their aquatic or terrestrial environments.
11.
Most nematodes are _______. Males are smaller than females and their sperm have an _______ structure.
Correct Answer
C. Dioecious; copulatory
Explanation
Most of the members in Phylum Nematoda are dioecious with amoeboid sperm, and males are smaller than females and have a bent tail for holding females for copulation.
12.
A rasping radula is characteristic of all mollusks EXCEPT _________.
Correct Answer
A. Bivalves
Explanation
Bivalves do not have a radula. Instead, they are filter feeders that use their gills to capture food particles from the water. The other groups, gastropods, cephalopods, and chitons, typically have a radula, which is a specialized feeding organ used for scraping or cutting food.
13.
The only class of mollusk to have a closed circulatory system includes the _______.
Correct Answer
D. Octopus
Explanation
Cephalopods, which include squids, octopuses, and cuttlefish, are the only class of mollusks that have a closed circulatory system. This system allows for more efficient oxygen and nutrient transport, supporting their active lifestyles and higher metabolic rates. The other classes of mollusks, such as bivalves, gastropods, and chitons, have open circulatory systems.
14.
The leech characteristic, _______________ , shared with oligochaetes is part of the evidence that leeches evolved from oligochaetes.
Correct Answer
C. Clitellum
Explanation
Leeches and oligochaetes (such as earthworms) both possess a clitellum, which is a specialized glandular segment involved in reproduction. This shared characteristic is part of the evidence that leeches evolved from oligochaetes. The clitellum is used in the formation of a cocoon for the protection of fertilized eggs.
15.
Annelida and Mollusca shared the characteristic of having a trochophore larva during their first larval stage.
Correct Answer
A. True
Explanation
Both Annelida (segmented worms) and Mollusca (mollusks) share the characteristic of having trochophore larvae during their first larval stage. The trochophore is a free-swimming, planktonic larva with a ring of cilia that is common to both phyla, indicating a possible evolutionary relationship between them.