1.
Cephalization
Correct Answer
A. Is characterized by the concentration of brains and sensory organs in the front end
Explanation
Cephalization refers to the evolutionary development of a head region in organisms, which is characterized by the concentration of brains and sensory organs in the front end. This adaptation allows for more efficient processing of sensory information and improved coordination of movements. It is a common feature observed in many invertebrates, such as insects and mollusks, as well as in higher organisms like vertebrates. This concentration of neural structures in the head region facilitates better control and integration of sensory inputs, leading to enhanced cognitive abilities and adaptive behaviors.
2.
Animals probably evolved from
Correct Answer
C. Colonial protozoa
Explanation
Animals probably evolved from colonial protozoa. Colonial protozoa are single-celled organisms that live in colonies. They exhibit some characteristics that are similar to animals, such as cell specialization and coordination within the colony. This suggests that colonial protozoa could have been the ancestors of animals, as they may have evolved into multicellular organisms with specialized cells and eventually developed into the diverse range of animal species we see today.
3.
Which of the following is found only in animals?
Correct Answer
D. HeterotropHy
Explanation
Heterotrophy is the correct answer because it is a characteristic that is exclusive to animals. Heterotrophy refers to the ability of an organism to obtain energy and nutrients by consuming other organisms. This mode of nutrition is not found in other kingdoms such as plants or fungi, making it a unique feature of animals.
4.
Organisms tha have one and only one plane of symmetry, which body parts are arranged in pairs, exhibit ___________ symmetry
Correct Answer
A. Bilateral
Explanation
Organisms that have one and only one plane of symmetry, where their body parts are arranged in pairs, exhibit bilateral symmetry. This means that if the organism is divided along its plane of symmetry, both halves will be mirror images of each other. This type of symmetry is commonly seen in animals, including humans, where the left and right sides of the body are similar in structure and arrangement.
5.
During embryonic development, the hollow ball of cells that forms is called the
Correct Answer
A. Blastula
Explanation
During embryonic development, the hollow ball of cells that forms is called the blastula. This stage occurs after the zygote undergoes multiple rounds of cell division, resulting in a hollow sphere of cells with a fluid-filled cavity called the blastocoel. The blastula is an important stage in development as it marks the beginning of gastrulation, where the cells rearrange and differentiate to form the three germ layers of the embryo. The blastula eventually gives rise to more complex structures, such as the gastrula and the various tissues and organs of the developing organism.
6.
During embryonic development, the opening of the primitive gut it called the
Correct Answer
C. Blastocoel
Explanation
During embryonic development, the opening of the primitive gut is called the blastocoel. The blastocoel is a fluid-filled cavity that forms within the blastula, which is an early stage of embryonic development. This opening eventually develops into the digestive system of the organism. The terms "mulara" and "glastocoel" are not recognized in embryology, and "none of the above" is not a specific term for the opening of the primitive gut.
7.
An animal that has a single opening through which food and wastes enter and exit have a(n) _______________ digestive track
Correct Answer
B. Incomplete
Explanation
An animal that has a single opening through which food and wastes enter and exit has an incomplete digestive track. This means that the digestive system does not have separate openings for the intake and elimination of food and waste. Instead, the animal uses the same opening for both functions. This is commonly seen in animals such as jellyfish and flatworms.
8.
During embryonic development, the solid ball of cells is called the __________, which means "berry"
Correct Answer
A. Mulara
Explanation
The given answer "mulara" is incorrect. The correct answer is "blastula". During embryonic development, the solid ball of cells is called blastula, which means "berry". This stage occurs after the morula stage, where the fertilized egg undergoes multiple cell divisions to form a hollow ball of cells with a fluid-filled cavity called the blastocoel. Therefore, the correct answer is blastula.
9.
Which of the following is NOT true about animals?
Correct Answer
D. They have cell walls
Explanation
Animals do not have cell walls. Unlike plants and fungi, animal cells do not have a rigid cell wall made of cellulose or chitin. Instead, animal cells are surrounded by a flexible cell membrane that allows for movement and interaction with the environment. This lack of cell walls is a characteristic feature of animals and distinguishes them from other organisms.
10.
Which of the following characteristics can you NOT compare animal relationships with?
Correct Answer
A. Type of Circulatory System
Explanation
You cannot compare animal relationships based on the type of circulatory system they have. Animal relationships can be compared based on characteristics such as symmetry, tissue type, type of body cavity, and type of gut. However, the circulatory system is not a characteristic that can be used to compare animal relationships.
11.
The function of the respiratory system is:
Correct Answer
A. To exchange CO2 for O2 between the tissues and the environment
Explanation
The correct answer is to exchange CO2 for O2 between the tissues and the environment. The respiratory system is responsible for the exchange of gases, specifically oxygen (O2) and carbon dioxide (CO2), between the body's tissues and the external environment. Oxygen is taken in from the environment and delivered to the cells, while carbon dioxide, a waste product of cellular metabolism, is removed from the cells and expelled from the body. This exchange of gases ensures that cells receive the oxygen they need for cellular respiration and that waste carbon dioxide is eliminated from the body.
12.
Animals that don't have an excretory system:
Correct Answer
C. Have cells that are close enough to the external environment for diffusion of metabolic wastes to occur
Explanation
Animals that don't have an excretory system are able to excrete metabolic wastes because their cells are located close enough to the external environment for diffusion of these wastes to occur. This means that the waste products can passively move from the cells to the surrounding environment without the need for a specialized excretory system.
13.
The large opening at the top of a sponge through which water exits is called the:
Correct Answer
A. Osculum
Explanation
The large opening at the top of a sponge through which water exits is called the osculum.
14.
The organisms that have a body cavity lined on the outside by mesoderm, and the inside by endoderm, are:
Correct Answer
A. Echinoderms and chordates
Explanation
Echinoderms and chordates are the organisms that have a body cavity lined on the outside by mesoderm and the inside by endoderm. This arrangement of tissue layers is known as a coelom, which provides support and protection for the internal organs. Echinoderms, such as starfish and sea urchins, and chordates, including vertebrates like fish, amphibians, reptiles, birds, and mammals, both exhibit this characteristic. The other options, annelids and ctenophores, arthropods and chordates, and cnidarians and sponges, do not have this specific body cavity arrangement.
15.
In spondes, the cells that have flagella, generate water currents, and filter the food out of the water are the:
Correct Answer
B. Choanocytes
Explanation
Choanocytes are the cells found in sponges that have flagella and are responsible for generating water currents. These currents help in filtering the food particles out of the water, allowing the sponge to obtain nutrients. Amoebocytes, on the other hand, are responsible for various functions like digestion, reproduction, and transportation of nutrients. Gemmules are specialized structures that help sponges survive harsh conditions, while spicules are skeletal structures that provide support and protection. Therefore, choanocytes best fit the description given in the question.
16.
Adult sponges
Correct Answer
A. Have body walls with many pores
Explanation
Adult sponges have body walls with many pores because sponges are filter feeders that rely on water flow to bring in food and oxygen. The pores in their body walls, called ostia, allow water to enter the sponge. As the water passes through the sponge, it collects particles of food and oxygen, which are then absorbed by the sponge's cells. Therefore, the presence of many pores in the body walls of adult sponges is essential for their feeding and respiration processes.
17.
As an animal develops, the ectoderm becomes the
Correct Answer
D. Skin and nervous tissue
Explanation
During the development of an animal, the ectoderm differentiates into various tissues. One of these tissues is the skin, which forms the outer protective layer of the animal's body. The ectoderm also gives rise to the nervous tissue, which forms the brain, spinal cord, and nerves. These tissues are crucial for the animal's sensory perception, coordination, and response to stimuli. Therefore, the correct answer is skin and nervous tissue.
18.
Which of the following is a characteristic associated only with cnidarians?
Correct Answer
B. Tentacles with stinging cells
Explanation
Cnidarians are characterized by having tentacles with stinging cells. This feature is unique to cnidarians and is used for capturing prey and for defense. Tentacles contain specialized cells called cnidocytes, which house stinging structures called nematocysts. When triggered, these stinging cells can inject venom into the prey or predator, immobilizing or deterring them. This adaptation is found in cnidarians such as jellyfish, sea anemones, and coral, and is not present in other animal groups.
19.
Cells that move throughout the sponges body wall to deliver food to the organism's cells are
Correct Answer
A. Amoebocytes
Explanation
Amoebocytes are cells that can move throughout the sponge's body wall to deliver food to the organism's cells. These cells are capable of phagocytosis, which allows them to engulf and digest food particles. They also play a role in removing waste materials from the sponge's body. Amoebocytes are essential for the nutrition and overall functioning of the sponge's cells, making them the correct answer to the question.
20.
As an animal develops, the mesoderm becomes the
Correct Answer
C. Muscle tissue
Explanation
During animal development, the mesoderm is one of the three primary germ layers that give rise to various tissues and organs. In this case, the correct answer is muscle tissue because the mesoderm differentiates into the muscular system. Muscle tissue is responsible for movement and contraction, and it develops from the mesodermal cells. The mesoderm also gives rise to other structures such as bones, blood vessels, and connective tissues, but in this context, the focus is on the development of muscle tissue.
21.
The function of the excretory system is:
Correct Answer
D. To remove nitrogenous wastes from tissues and maintain homeostasis of electrolytes
Explanation
The excretory system is responsible for removing nitrogenous wastes from tissues and maintaining the balance of electrolytes in the body. Nitrogenous wastes, such as urea, are produced as a result of protein metabolism and need to be eliminated from the body to prevent toxicity. Additionally, the excretory system helps regulate the levels of electrolytes, such as sodium, potassium, and calcium, in the body to maintain homeostasis.
22.
Spongin is
Correct Answer
D. The protein found in sponge skeltons
Explanation
Spongin is the protein found in sponge skeletons. Sponges have a unique skeletal structure made up of either mineral crystals or a protein called spongin. In this case, spongin refers to the protein component of sponge skeletons. Spongin provides support and structure to the sponge, allowing it to maintain its shape and form.
23.
Animals that don't have a circulatory system:
Correct Answer
D. Are small enough for diffusion to do the job
Explanation
Animals that don't have a circulatory system are small enough for diffusion to do the job. Diffusion is the process by which molecules move from an area of high concentration to an area of low concentration. In small animals, such as flatworms or some insects, their body size and structure allow for efficient diffusion of oxygen, nutrients, and waste products without the need for a circulatory system. This is possible because their small size provides a large enough surface area-to-volume ratio, allowing for the exchange of gases and nutrients directly through their body surface.
24.
Which of the following distinguishes sponges from other animals
Correct Answer
C. Their cells are not organized into tissues
Explanation
Sponges are unique among animals because their cells are not organized into tissues. Unlike other animals, sponges lack specialized tissues and organs. Instead, their cells are loosely arranged and perform various functions independently. This allows sponges to have a simple body structure and perform basic functions like feeding, respiration, and reproduction. The absence of tissue organization is a key characteristic that distinguishes sponges from other animals.
25.
Sponges obtain food
Correct Answer
C. By filtering small organisms from the water
Explanation
Sponges obtain food by filtering small organisms from the water. They have specialized cells called choanocytes that have flagella to create water currents and filter out tiny food particles. These particles are then engulfed and digested by the sponge's cells. This method of feeding is known as filter feeding and is a common way for sponges to obtain nutrients.
26.
Phylum Playthelminthes are...
Correct Answer
B. Flatworms (planaria, flukes, tapeworms)
Explanation
The correct answer is flatworms (planaria, flukes, tapeworms). Phylum Platyhelminthes is a group of invertebrate animals that includes flatworms. Flatworms are characterized by their flat, ribbon-like body shape. They can be found in various habitats, including freshwater, marine, and terrestrial environments. Examples of flatworms include planaria, which are free-living organisms found in freshwater, flukes, which are parasitic worms that infect various animals, and tapeworms, which are also parasitic worms that live in the intestines of vertebrates. Therefore, the correct answer is flatworms.
27.
Phylum Cnidaria include...
Correct Answer
A. Jellyfishes, sea anemones, hydras, and corals
Explanation
The correct answer is jellyfishes, sea anemones, hydras, and corals. Phylum Cnidaria is a group of animals that includes jellyfishes, sea anemones, hydras, and corals. These organisms are characterized by their specialized stinging cells called cnidocytes, which they use for capturing prey and defense. They also have a simple body structure with a central cavity surrounded by tentacles. Sponges belong to a different phylum called Porifera, and comb jellies belong to the phylum Ctenophora. Therefore, the correct answer is jellyfishes, sea anemones, hydras, and corals.
28.
The planula finds a nice place in a polyp and reproduces asexually in what lifecycle?
Correct Answer
C. Jellyfish (medusa)
Explanation
The planula is a larval stage in the life cycle of jellyfish (medusa). During this stage, the planula settles on a suitable substrate, such as a polyp, and undergoes asexual reproduction. This means that it can produce offspring without the need for fertilization. Eventually, the planula develops into a polyp, which then gives rise to the medusa stage of the jellyfish life cycle. Therefore, the correct answer is jellyfish (medusa).
29.
Which of the following is NOT a disease caused by roundworms?
Correct Answer
E. Athlete's Foot
Explanation
Athlete's Foot is not caused by roundworms, but rather by a fungal infection. Roundworms, on the other hand, are responsible for diseases such as Ascaris, Hookworms, Tricheinella, and Pin worms/Filarial worms.