Quiz 1_sth2073 Invertebrate Biology

Osmoregulation is the process by which organisms regulate the balance of water and solutes in their bodies. In Phylum Protozoa, osmoregulation is achieved through the use of a contractile vacuole. The contractile vacuole acts as a water pump, collecting excess water from the cytoplasm and expelling it out of the cell. This helps maintain the proper balance of water and solutes within the cell, allowing the protozoa to survive in various environments. Therefore, the statement "Osmoregulation in Phylum Protozoa is happen by means of a contractile vacuole" is true.

A group of species sharing an immediate ancestor but not including all descendants is known as paraphyletic. This means that the group includes some, but not all, of the descendants of a common ancestor. It is different from a monophyletic group, which includes all descendants of a common ancestor. In a paraphyletic group, some branches of the evolutionary tree are excluded, leading to a classification that does not accurately represent the true relationships between species.

Members of Class Calcarea are distinguished from other classes by having spicules composed of calcium carbonate. Calcium carbonate is a common mineral found in the shells of marine organisms, such as corals and mollusks. In the case of Class Calcarea, these spicules provide structural support and protection for the organisms. This is a defining characteristic of this class, as other classes may have spicules composed of different materials or may not have spicules at all.

Protozoans are single-celled organisms that reproduce asexually through binary fission and budding. Binary fission is a process in which the cell divides into two identical daughter cells, while budding involves the formation of a smaller daughter cell that eventually separates from the parent cell. Both methods allow for the production of genetically identical offspring, ensuring the clonal reproduction of the protozoan. Therefore, the correct answer is binary fission and budding, or budding and binary fission.

Entamoeba histolytica is responsible for causing amoebiosis, which is characterized by internal inflammation. This parasitic amoeba infects the intestines and can cause severe gastrointestinal symptoms such as diarrhea, abdominal pain, and inflammation of the intestinal wall. If left untreated, Entamoeba histolytica can invade other organs, leading to more serious complications like liver abscesses. Therefore, this organism is directly associated with the internal inflammation observed in cases of amoebiosis.

Tripoblastic animals are organisms which have three germ layers; ectoderm, endoderm and mesoderm.

Ostia = allows water in; oscula = lets water out

Archaeocytes are amoeboid cells that carry out phagocytosis. Other than that, they serve as storage of digested food materials.

Members of Phylum Porifera are divided into classes based on the chemical composition and morphology of their support elements. The chemical composition refers to the materials that make up the support structures, such as calcium carbonate or silica. The morphology refers to the shape and structure of these support elements, which can vary among different classes of Porifera. Both factors play a crucial role in classifying and distinguishing the different classes within this phylum.