Q: Class bivalvia ("two shells") includes clams, oysters, mussels, scallops, and these? Read this paragraph and choose the correct option from the provided answers: Class Bivalvia ("two shells") includes clams, oysters, mussels, scallops, and geoducks. Members of this class are found in marine as well as freshwater habitats. As the name suggests, bivalves are enclosed in a pair of shells (valves are commonly called "shells") that are hinged at the dorsal end by shell ligaments as well as shell teeth (Figure 28.22). The overall morphology is laterally flattened, and the head region is poorly developed. Eyespots and statocysts may be absent in some species. Since these animals are suspension feeders, a radula is absent in this class of mollusks. Respiration is facilitated by a pair of ctenidia, whereas excretion and osmoregulation are brought about by a pair of nephridia. Bivalves often possess a large mantle cavity. In some species, the posterior edges of the mantle may fuse to form two siphons that serve to take in and exude water. Choices: - grendels - crabs - octopuss - geoducks A:
geoducks

(Question)
Q: Both oxygen and glucose are transported within the body via what? Read this paragraph and choose the correct option from the provided answers: Oxygen is just one substance transported by the blood. The blood also transports nutrients such as glucose. Choices: - bone - heart - marrow - blood A:
(Answer)
blood

Ques: Q: How is blood supplied from the mother to the fetus? Read this paragraph and choose the correct option from the provided answers: Hemoglobin of the Fetus The fetus has its own circulation with its own erythrocytes; however, it is dependent on the mother for oxygen. Blood is supplied to the fetus by way of the umbilical cord, which is connected to the placenta and separated from maternal blood by the chorion. The mechanism of gas exchange at the chorion is similar to gas exchange at the respiratory membrane. However, the partial pressure of oxygen is lower in the maternal blood in the placenta, at about 35 to 50 mm Hg, than it is in maternal arterial blood. The difference in partial pressures between maternal and fetal blood is not large, as the partial pressure of oxygen in fetal blood at the placenta is about 20 mm Hg. Therefore, there is not as much diffusion of oxygen into the fetal blood supply. The fetus' hemoglobin overcomes this problem by having a greater affinity for oxygen than maternal hemoglobin (Figure 22.27). Both fetal and adult hemoglobin have four subunits, but two of the subunits of fetal hemoglobin have a different structure that causes fetal hemoglobin to have a greater affinity for oxygen than does adult hemoglobin. Choices: - brain stem - vagina - spinal cord - umbilical cord A:
Ans: umbilical cord

(Q).
Q: Antibiotics can cure most infections that are caused by what? Read this paragraph and choose the correct option from the provided answers: Health care has been improving over the most recent centuries. Vaccines were developed that could prevent many diseases ( Figure below ). Antibiotics were discovered that could cure most infections caused by bacteria. Together, these two advances saved countless lives. Choices: - bacterium - algae - bile - bacteria A:
(A).
bacteria

Ques:Q: Vertebrates are all chordates that have a what? Read this paragraph and choose the correct option from the provided answers: Living species of chordates are classified into three major subphyla: Vertebrata, Urochordata, and Cephalochordata. Vertebrates are all chordates that have a backbone. The other two subphyla are invertebrate chordates that lack a backbone. Members of the subphylum Urochordata are tunicates (also called sea squirts). Members of the subphylum Cephalochordata are lancelets . Both tunicates and lancelets are small and primitive. They are probably similar to the earliest chordates that evolved more than 500 million years ago. Choices: - circulatory system - fossil - brain - backbone A:

Ans:backbone

Q: Energy from sunlight enters many ecosystems through what process? Read this paragraph and choose the correct option from the provided answers: Ecosystems need energy. Many ecosystems get their energy in the form of sunlight, which enters the ecosystem through photosynthesis . This energy then flows through the ecosystem, passed from producers to consumers . Plants are producers in many ecosystems. Energy flows from plants to the herbivores that eat the plants, and then to carnivores that eat the herbivores. The flow of energy depicts interactions of organisms within an ecosystem. Choices: - multiplication - reproduction - isolation - photosynthesis A:
photosynthesis