Q: What are microscopic vessels with very thin, porous walls? Read this paragraph and choose the correct option from the provided answers: Choices: - veins - arteries - valves - capillaries A:
capillaries

(Question)
Q: Protozoa are generally difficult to identify due to what? Read this paragraph and choose the correct option from the provided answers: 22.10 Protozoa As heterotrophs, protozoa scavenge materials from their surroundings. Others are predators which actively hunt or ambush small organisms such as bacteria and other protozoa for a source of nutrition. Protozoa can be parasitic as well; they may live inside larger organisms, like humans. Most protozoa live as single cells, although a few form colonies. Protozoa are generally difficult to identify due to their varied shape. They may appear as jelly-like blobs, spherical sunbursts, or a flattened leaf. Tiny blood parasites may be only 2 m long. On the other hand, shell-covered marine may be 5 cm or more in diameter. Furthermore, different protozoans have their own complex life cycles. The complexity has led certain organisms to be mistakenly classified for other species. Nevertheless, protozoa can move, and so, they are classified based on their methods of locomotion. Characteristics of Protozoa : About 30,000 species known About 10,000 species are pathogenic, including some of the worst human diseases heterotrophic highly variable in form and life cycle. Choices: - their hidden shape - their resting shape - their formation shape - their varied shape A:
(Answer)
their varied shape

Ques: Q: What do the liver, gallbladder, and pancreas contribute that aid in digestion? Read this paragraph and choose the correct option from the provided answers: The liver, gallbladder, and pancreas contribute chemicals that aid in digestion. Choices: - contaminants - crystals - plasma - chemicals A:
Ans: chemicals

(Q).
Q: What is the name of the temporary organ that begins to form from the trophoblast layer of cells shortly after implantation? Read this paragraph and choose the correct option from the provided answers: The placenta is a temporary organ that begins to form from the trophoblast layer of cells shortly after implantation. (For an animation showing how the placenta forms, go to link below. ) The placenta continues to develop and grow to meet the needs of the growing fetus. A fully developed placenta, like the one in Figure above , is made up of a large mass of blood vessels from both the mother and fetus. The maternal and fetal vessels are close together but separated by tiny spaces. This allows the mother's and fetus's blood to exchange substances across their capillary walls without the blood actually mixing. Choices: - uterus - embryo - appendix - placenta A:
(A).
placenta

Ques:Q: As a diver descends, the increase in pressure causes the body's air pockets in the ears and lungs to do what? Read this paragraph and choose the correct option from the provided answers: from the atmosphere at sea level. As a diver descends, the increase in pressure causes the body's air pockets in the ears and lungs to compress; on the ascent, the decrease in pressure causes these air pockets to expand, potentially rupturing eardrums or bursting the lungs. Divers must therefore undergo equalization by adding air to body airspaces on the descent by breathing normally and adding air to the mask by breathing out of the nose or adding air to the ears and sinuses by equalization techniques; the corollary is also true on ascent, divers must release air from the body to maintain equalization. Buoyancy, or the ability to control whether a diver sinks or floats, is controlled by the buoyancy compensator (BCD). If a diver is ascending, the air in his BCD expands because of lower pressure according to Boyle's law (decreasing the pressure of gases increases the volume). The expanding air increases the buoyancy of the diver, and she or he begins to ascend. The diver must vent air from the BCD or risk an uncontrolled ascent that could rupture the lungs. In descending, the increased pressure causes the air in the BCD to compress and the diver sinks much more quickly; the diver must add air to the BCD or risk an uncontrolled descent, facing much higher pressures near the ocean floor. The pressure also impacts how long a diver can stay underwater before ascending. The deeper a diver dives, the more compressed the air that is breathed because of increased pressure: If a diver dives 33 feet, the pressure is 2 ATA and the air would be compressed to one-half of its original volume. The diver uses up available air twice as fast as at the surface. Choices: - heat up - expand - blow up - compress A:

Ans:compress

Ques:Q: Which is the ultimate energy source in a bear's food chain? Read this paragraph and choose the correct option from the provided answers: Bears get their energy from their food. Brown bears eat a varied diet, from nuts and berries to fish and other animals. When bears eat a berry, they are obtaining energy that the plant originally captured from the sun. Even when a bear eats another animal, the energy in that animal ultimately came from eating a producer that captured the sun's energy. Choices: - decomposers - plants - heat - sun A:

Ans:
sun