1.
A sponge has the same basic structure as which of the following
Correct Answer
A. A bag
Explanation
A sponge has the same basic structure as a bag because both have a porous and flexible material that can absorb and hold liquids. Just like a sponge, a bag can expand and contract to accommodate different contents, making it a suitable comparison in terms of structure and function.
2.
What is an amoebocyte?
Correct Answer
B. An amoeba-like cell that supplies nutrition and removes wastes from sponge body cells
Explanation
An amoebocyte is an amoeba-like cell that supplies nutrition and removes wastes from sponge body cells. This type of cell plays a crucial role in the functioning and survival of sponges by providing nutrients to other cells and eliminating waste materials. Amoebocytes are responsible for transporting and distributing food particles and oxygen throughout the sponge's body, as well as removing metabolic waste products. They are essential for maintaining the overall health and functioning of the sponge's body cells.
3.
What do amoebocytes do?
Correct Answer
A. Wander about the mesenchyme, supplying the rest of the sponge's cells with nutrients, and carrying away other wastes
Explanation
Amoebocytes are specialized cells found in sponges that play a crucial role in their physiology. They wander through the mesenchyme, which is the gelatinous matrix that makes up the sponge's body, and perform several important functions. One of their main roles is to supply nutrients to the other cells of the sponge, ensuring their survival and proper functioning. Additionally, amoebocytes also help in removing waste materials produced by the sponge's cells, maintaining a clean and healthy environment within the organism.
4.
How do the other cells of the sponge survive if the collar cells take in all the food
Correct Answer
D. The collar cells release nutrients into the mesenchyme
Explanation
The collar cells release nutrients into the mesenchyme, which is a gelatinous matrix that surrounds the cells of the sponge. This allows the other cells of the sponge to obtain the necessary nutrients for survival.
5.
Water enters a sponge by passing through blank in the sponge's body wall
Correct Answer
pores
Explanation
Water enters a sponge by passing through small openings called pores in the sponge's body wall. These pores allow water to flow into the sponge, where it is absorbed and held within the sponge's structure. The sponge's body wall is made up of a network of channels and chambers that are interconnected through these pores, allowing water to move freely throughout the sponge's body.
6.
The inside of a sponge is lined by cells called blank .
Correct Answer
choanocytes
Explanation
The inside of a sponge is lined by cells called choanocytes. Choanocytes are specialized cells that have a collar-like structure with a flagellum projecting from it. These cells create water currents and help in capturing food particles for the sponge. They also play a role in gas exchange and waste removal within the sponge.
7.
The beating of each choanocytes blank draws water down through its collar.
Correct Answer
flagella
Explanation
Each choanocyte has a flagellum, which is a whip-like structure that beats to create a current and draw water down through its collar. The flagella of choanocytes are responsible for creating the flow of water in sponges, allowing them to filter feed and capture food particles.
8.
Blank like bacteria and algae are trapped in the collar.
Correct Answer
organisms
Explanation
The given sentence states that "blank like bacteria and algae are trapped in the collar." The word "organisms" is the correct answer as it is a general term that encompasses both bacteria and algae. Bacteria and algae are both types of organisms, so they fit perfectly in the blank space.
9.
These organisms the move toward the cell's cytoplasm, where they are ingested through blank.
Correct Answer
endocytosis
Explanation
Endocytosis is the process by which cells engulf external substances by forming a vesicle around them and bringing them into the cell's cytoplasm. This allows the cell to take in and internalize various molecules and particles, including microorganisms. In this context, the organisms mentioned in the question are moving towards the cell's cytoplasm, suggesting that they are being taken in by the cell through the process of endocytosis.
10.
For the sponge's body to function effectively, the:
Correct Answer
A. Body wall must be rigid enough to prevent the sponge from collapsing in on itself
Explanation
The body wall of a sponge must be rigid enough to prevent the sponge from collapsing in on itself. This is because sponges are simple multicellular organisms that lack a skeleton or internal support structures. The body wall provides the necessary support for the sponge's body and helps maintain its shape. If the body wall were soft, it would not be able to provide the necessary rigidity to prevent collapse. Therefore, a rigid body wall is essential for the sponge's body to function effectively.
11.
The skeleton of most sponges is not a fixed framework like your skeleton, but rather a:
Correct Answer
C. Diffuse network of fibers or minerals
Explanation
Sponges do not have a fixed framework for their skeleton like humans do. Instead, their skeleton is made up of a diffuse network of fibers or minerals. This means that the skeleton of a sponge is not a solid structure, but rather a loose arrangement of fibers or minerals that provide support and shape to the sponge's body. This flexible skeleton allows sponges to adapt to their environment and change their shape as needed.
12.
The skeletons of most sponges are made of a resilient flexible protein fiber called blank
Correct Answer
spongin
Explanation
Sponges have skeletons made of a resilient flexible protein fiber called spongin. Spongin provides structural support to the sponge, allowing it to maintain its shape and form. This protein fiber is known for its flexibility, which allows the sponge to withstand external pressures and water currents without breaking. Spongin also gives sponges their characteristic soft and squishy texture. Overall, spongin is an essential component of sponge skeletons, providing them with the necessary strength and flexibility.
13.
A few sponges have more brittle skeletons composed of tiny hard needles of silica or calcium carbonate called blank.
Correct Answer
spicules
Explanation
Sponges can have skeletons made of either silica or calcium carbonate. These skeletons are composed of tiny hard needles called spicules.
14.
Sponges will blank when cut into pieces.
Correct Answer
regenerate
Explanation
Sponges have the ability to regenerate when cut into pieces. This means that if a sponge is cut into multiple pieces, each piece has the ability to grow back and form a complete sponge. This regenerative ability is a unique characteristic of sponges and allows them to recover and continue their growth even after being damaged or fragmented.
15.
When the pieces are returned to the ocean, each bit of sponge, however small, will grow into blank.
Correct Answer
a complete new sponge
Explanation
When the pieces of sponge are returned to the ocean, each bit, no matter how small, has the ability to grow into a complete new sponge. This suggests that sponges have a regenerative ability, where even tiny fragments can develop into fully formed sponges. This phenomenon highlights the resilience and reproductive capabilities of sponges in their natural environment.
16.
Sponges frequently reproduce by simply blank.
Correct Answer
breaking into fragments
Explanation
Sponges frequently reproduce by breaking into fragments. This means that a sponge can break apart into smaller pieces, and each of these fragments has the ability to grow into a new sponge. This method of reproduction allows sponges to quickly colonize new areas and expand their population.
17.
When sponges reproduce by breaking into fragments, this is a form of blank.
Correct Answer
asexual reproduction
Explanation
When sponges reproduce by breaking into fragments, it is considered a form of asexual reproduction. Asexual reproduction refers to the process of producing offspring without the involvement of gametes or the fusion of genetic material from two parents. In this case, the sponge fragments are able to regenerate and grow into new individuals without the need for fertilization or the formation of specialized reproductive cells. This method allows for the rapid and efficient multiplication of sponges, as each fragment has the potential to develop into a fully functional organism.
18.
What are gemmules?
Correct Answer
D. Clusters of amoebocytes encased withing protective coats
Explanation
Gemmules are clusters of amoebocytes encased within protective coats. Amoebocytes are specialized cells found in sponges that are responsible for various functions such as digestion, reproduction, and structural support. Gemmules are formed by the aggregation of these cells and are capable of surviving harsh environmental conditions. They serve as a means of asexual reproduction and can remain dormant until conditions become favorable for their growth and development.
19.
When living conditions become hars, some freshwater sponges ensure their survival by forming blank .
Correct Answer
gemmules
Explanation
When living conditions become harsh, some freshwater sponges ensure their survival by forming gemmules. Gemmules are specialized structures produced by certain sponges that contain a cluster of cells surrounded by a protective coating. These structures allow the sponge to withstand unfavorable conditions such as drought or cold temperatures. Inside the gemmules, the cells remain dormant until conditions improve, at which point they can develop into new sponges and ensure the species' survival.
20.
Most sponges are not exclusively:
Correct Answer
A. Male or female
Explanation
Most sponges are not exclusively male or female. This means that they can have both male and female reproductive organs, or they can change their sex from male to female or vice versa. This is known as hermaphroditism, which is a common reproductive strategy in many marine invertebrates, including sponges. Hermaphroditism allows sponges to maximize their reproductive success by being able to both produce and receive gametes during mating. Therefore, the correct answer is "male or female."
21.
A sponge is a blank , an organism that produces both eggs and sperm.
Correct Answer
hermaphrodite
Explanation
A sponge is a hermaphrodite, which means it is an organism that produces both eggs and sperm.
22.
An organism that produces both eggs and sperm is a:
Correct Answer
B. HermapHrodite
Explanation
An organism that produces both eggs and sperm is called a hermaphrodite. This means that they have both male and female reproductive organs and can self-fertilize or mate with another individual of the same species. This allows for increased reproductive efficiency and flexibility in finding a mate.
23.
Eggs and sperm are produced:
Correct Answer
C. At different times
Explanation
Eggs and sperm are produced at different times in most organisms. This is because the production of eggs and sperm, also known as gametogenesis, occurs through different processes. In females, eggs are produced through a process called oogenesis, which begins before birth and continues throughout the reproductive years. In males, sperm are produced through a process called spermatogenesis, which begins at puberty and continues throughout life. Therefore, eggs and sperm are not produced simultaneously, but rather at different times in the reproductive cycle of an organism.
24.
Eggs and sperm are produced at different times, so blank is avoided.
Correct Answer
self-fertilization
Explanation
Self-fertilization is avoided because eggs and sperm are produced at different times. Self-fertilization occurs when an organism fertilizes its own eggs with its own sperm, which is not possible if eggs and sperm are produced at different times.
25.
The advantage of hermaphroditism is that:
Correct Answer
A. The sperm of any individual can fertilize the egg of any other individual
Explanation
In hermaphroditism, an individual possesses both male and female reproductive organs. This allows for self-fertilization, where an individual can fertilize its own eggs. However, the advantage of hermaphroditism lies in the fact that the sperm of any individual can fertilize the egg of any other individual. This increases genetic diversity within a population and promotes outcrossing, which can lead to the production of offspring with greater genetic variation and potentially increased adaptability to changing environments.
26.
Sponges can have a combination of a supportive skeleton composed of soft spongin fibers and hard spicules.
Correct Answer
A. True
Explanation
Sponges can indeed have a combination of a supportive skeleton composed of soft spongin fibers and hard spicules. This means that their structure can consist of both flexible and rigid components, providing them with the necessary support and protection.
27.
80% of all sponges are calcareous
Correct Answer
B. False
Explanation
80% of all spongers are demosponges