Ques: Answer the following question given this paragraph: Q: What are typically arranged into complex tubular networks with extensive surface areas? Choices: - alveoli - hair follicles - Golgi apparatus - transport epithelia A:
Ans: transport epithelia

Ques: Answer the following question given this paragraph: The earliest and simplest vertebrates are fish. Fish also have the greatest number of vertebrate classes. Think about some of the fish you are familiar with, such as fish you eat or fish you may have seen in aquariums. Q: What are the earliest and simplest vertebrates? Choices: - whales - birds - bears - fish A:
Ans: fish

Ques: Answer the following question given this paragraph: The structure of the different types of blood vessels reflects their function or layers. There are three distinct layers, or tunics, that form the walls of blood vessels (Figure 40.16). The first tunic is a smooth, inner lining of endothelial cells that are in contact with the red blood cells. The endothelial tunic is continuous with the endocardium of the heart. In capillaries, this single layer of cells is the location of diffusion of oxygen and carbon dioxide between the endothelial cells and red blood cells, as well as the exchange site via endocytosis and exocytosis. The movement of materials at the site of capillaries is regulated by vasoconstriction, narrowing of the blood vessels, and vasodilation, widening of the blood vessels; this is important in the overall regulation of blood pressure. Veins and arteries both have two further tunics that surround the endothelium: the middle tunic is composed of smooth muscle and the outermost layer is connective tissue (collagen and elastic fibers). The elastic connective tissue stretches and supports the blood vessels, and the smooth muscle layer helps regulate blood flow by altering vascular resistance through vasoconstriction and vasodilation. The arteries have thicker smooth muscle and connective tissue than the veins to accommodate the higher pressure and speed of freshly pumped blood. The veins are thinner walled as the pressure and rate of flow are much lower. In addition, veins are structurally different than arteries in that veins have valves to prevent the backflow of blood. Because veins have to work against gravity to get blood back to the heart, contraction of skeletal muscle assists with the flow of blood back to the heart. Q: Three distinct layers or tunics form the walls of what structures; the first is a smooth, inner lining of endothelial cells in contact with the red blood cells? Choices: - lungs - white blood cells - alveoli - blood vessels A:
Ans: blood vessels

Ques: Answer the following question given this paragraph: Acids and bases are important in living things because most enzymes can do their job only at a certain level of acidity. Cells secrete acids and bases to maintain the proper pH for enzymes to work. For example, every time you digest food, acids and bases are at work in your digestive system. Consider the enzyme pepsin, which helps break down proteins in the stomach. Pepsin needs an acidic environment to do its job, and the stomach secretes a strong acid that allows pepsin to work. However, when stomach contents enter the small intestine, the acid must be neutralized. This is because enzymes in the small intestine need a basic environment in order to work. An organ called the pancreas secretes a strong base into the small intestine, and this base neutralizes the acid. Q: In what organ does pepsin help break down proteins? Choices: - kidney - liver - skin - stomach A:
Ans:
stomach