Answer the following question given this paragraph: Hair and nails are made of keratin, a tough protein. Q: Hair and nails are made of what? Choices: - chromatin - proteins - cellulose - keratin A:
keratin
Answer the following question given this paragraph: Earth and the other planets in the solar system make elliptical orbits around the Sun. The ellipses in this image are highly exaggerated. Q: What do earth and the other planets in the solar system make around the sun? Choices: - radial orbits - smooth orbits - elevated orbits - elliptical orbits A:
elliptical orbits
Q: Answer the following question given this paragraph: Diagram of a Cytomegalovirus. The capsid encloses the genetic material of the virus. The envelope which surrounds the capsid is typically made from portions of the host cell membranes (phospholipids and proteins). Not all viruses have a viral envelope. Q: What encloses the genetic material of the virus? Choices: - mitochondria - nuclei - the spindle - the capsid A:
A: the capsid
Question: 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:
Answer: blood vessels
*Question*
Answer the following question given this paragraph: Anaphase is the phase in which the sister chromatids separate. The sister chromatids are pulled apart by the shortening of the microtubules of the spindles, similar to the reeling in of a fish by the shortening of the fishing line. One sister chromatid moves to one pole of the cell, and the other sister chromatid moves to the opposite pole. This process occurs when the proteins that bind sister chromatids together are cleaved, resulting in unattached identical chromosomes, essentially separate daughter chromosomes. These separate chromosomes are pulled apart by shortening spindle fibers, and pulled toward the centrosomes to which they are attached. At the end of anaphase the spindle fibers degrade. At this time, each pole of the cell has a complete set of chromosomes, identical to the amount of DNA at the beginning of G 1 of the cell cycle. Q: In which phase do the sister chromatids separate? Choices: - prophase - passivation - latent phase - anaphase A:
**Answer**
anaphase
(Q).
Answer the following question given this paragraph: Controlling muscles and maintaining balance are just two of the functions of the human nervous system. What else does the nervous system do?. Q: What is one function of the nervous system in humans? Choices: - controlling emotion - producing hormones - controlling thought - controlling muscles A:
(A).
controlling muscles