Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Context: In the present study, we tested the hypothesis that having migraine in middle age is related to late-life parkinsonism and a related disorder, restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED). The AGES-Reykjavik cohort (born 1907-1935) has been followed since 1967. Headaches were classified based on symptoms assessed in middle age. From 2002 to 2006, 5,764 participants were reexamined to assess symptoms of parkinsonism, diagnosis of Parkinson disease (PD), family history of PD, and RLS/WED. Subjects with midlife migraine, particularly migraine with aura (MA), were in later life more likely than others to report parkinsonian symptoms (odds ratio [OR]MA = 3.6 [95% CI 2.7-4.8]) and diagnosed PD (ORMA = 2.5 [95% CI 1.2-5.2]). Women with MA were more likely than others to have a parent (ORMA = 2.26 [95% CI 1.3-4.0]) or sibling (ORMA = 1.78 [95% CI 1.1-2.9]) with PD. Late-life RLS/WED was increased for headache generally. Associations were independent of cardiovascular disease and MRI-evident presumed ischemic lesions. These findings suggest there may be a common vulnerability to, or consequences of, migraine and multiple indicators of parkinsonism. Additional genetic and longitudinal observational studies are needed to identify candidate pathways that may account for the comorbid constellation of symptoms.
Question: Willis-Ekbom disease is also known as?
restless legs syndrome

Context: From the outside, the skin looks plain and simple, as you can see in Figure 16.5. But at a cellular level, theres nothing plain or simple about it. A single square inch of skin contains about 20 blood vessels, hundreds of sweat glands, and more than a thousand nerve endings. It also contains tens of thousands of pigment-producing cells. Clearly, there is much more to skin than meets the eye! For a dramatic introduction to the skin, watch this video: MEDIA Click image to the left or use the URL below. URL: The skin is only about 2 mm thick, or about as thick as the cover of a book. Although it is very thin, it consists of two distinct layers, called the epidermis and the dermis. You can see both layers and some of their structures in Figure 16.6. Refer to the figure as you read about the epidermis and dermis below. The epidermis is the outer layer of skin. It consists almost entirely of epithelial cells. There are no blood vessels, nerve endings, or glands in this skin layer. Nonetheless, this layer of skin is very active. It is constantly being renewed. How does this happen? 1. The cells at the bottom of the epidermis are always dividing by mitosis to form new cells. 2. The new cells gradually move up through the epidermis toward the surface of the body. As they move, they produce the tough, fibrous protein called keratin. 3. By the time the cells reach the surface, they have filled with keratin and died. On the surface, the dead cells form a protective, waterproof layer. 4. Dead cells are gradually shed from the surface of the epidermis. As they are shed, they are replaced by other dead cells that move up from below. The epidermis also contains cells called melanocytes. You can see a melanocyte in Figure 16.7. Melanocytes produce melanin. Melanin is a brown pigment that gives skin much of its color. Everyones skin has about the same number of melanocytes per square inch. However, the melanocytes of people with darker skin produce more melanin. The amount of melanin that is produced depends partly on your genes and partly on how much ultraviolet light strikes your skin. The more light you get, the more melanin your melanocytes produce. This explains why skin tans when its exposed to sunlight. The dermis is the inner layer of skin. It is made of tough connective tissue. The dermis is attached to the epidermis by fibers made of the protein collagen. The dermis is where most skin structures are located. Look again at Figure pain, pressure, and temperature. If you cut your skin and it bleeds, the cut has penetrated the dermis and damaged a blood vessel. The cut probably hurts as well because of the nerve endings in this skin layer. The dermis also contains hair follicles and two types of glands. You can see some of these structures in Figure 16.8. Hair follicles are structures where hairs originate. Each hair grows out of a follicle, passes up through the epidermis, and extends above the skin surface. Sebaceous glands are commonly called oil glands. They produce an oily substance called sebum. Sebum is secreted into hair follicles. Then it makes its way along the hair shaft to the surface of the skin. Sebum waterproofs the hair and skin and helps prevent them from drying out. Sweat glands produce the salty fluid known as sweat. Sweat contains excess water, salts, and other waste products. Each sweat gland has a duct that passes through the epidermis. Sweat travels from the gland through the duct and out through a pore on the surface of the skin. You couldnt survive without your skin. It has many important functions. In several ways, it helps maintain homeostasis. The main function of the skin is controlling what enters and leaves the body. It prevents the loss of too much water from the body. It also prevents bacteria and other microorganisms from entering the body. Melanin in the epidermis absorbs ultraviolet light. This prevents the light from reaching and damaging the dermis. The skin helps maintain a constant body temperature. It
Question: __major organ of the integumentary system
skin

Context: Speed is an important aspect of motion. It is a measure of how fast or slow something moves. It depends on how far something travels and how long it takes to travel that far. Speed can be calculated using this general formula: speed = distance time A familiar example is the speed of a car. In the U.S., this is usually expressed in miles per hour (see Figure 12.6). If your family makes a car trip that covers 120 miles and takes 3 hours, then the cars speed is: speed = 120 mi = 40 mi/h 3h The speed of a car may also be expressed in kilometers per hour (km/h). The SI unit for speed is meters per second (m/s). When you travel by car, you usually dont move at a constant speed. Instead you go faster or slower depending on speed limits, traffic, traffic lights, and many other factors. For example, you might travel 65 miles per hour on a highway but only 20 miles per hour on a city street (see Figure 12.7). You might come to a complete stop at traffic lights, slow down as you turn corners, and speed up to pass other cars. The speed of a moving car or other object at a given instant is called its instantaneous speed. It may vary from moment to moment, so it is hard to calculate. Its easier to calculate the average speed of a moving object than the instantaneous speed. The average speed is the total distance traveled divided by the total time it took to travel that distance. To calculate the average speed, you can use the general formula for speed that was given above. Suppose, for example, that you took a 75-mile car trip with your family. Your instantaneous speed would vary throughout the trip. If the trip took a total of 1.5 hours, your average speed for the trip would be: average speed = 75 mi = 50 mi/h 1.5 h You can see a video about instantaneous and average speed and how to calculate them at this URL: MEDIA Click image to the left or use the URL below. URL: You Try It! Problem: Terri rode her bike very slowly to the top of a big hill. Then she coasted back down the hill at a much faster speed. The distance from the bottom to the top of the hill is 3 kilometers. It took Terri 15 minutes to make the round trip. What was her average speed for the entire trip? The motion of an object can be represented by a distance-time graph like the one in Figure 12.8. A distance-time graph shows how the distance from the starting point changes over time. The graph in Figure 12.8 represents a bike trip. The trip began at 7:30 AM (A) and ended at 12:30 PM (F). The rider traveled from the starting point to a destination and then returned to the starting point again. In a distance-time graph, the speed of the object is represented by the slope, or steepness, of the graph line. If the line is straight, like the line between A and B in Figure 12.8, then the speed is constant. The average speed can be calculated from the graph. The change in distance (represented by Dd) divided by the change in time (represented by Dt): speed = Dd Dt For example, the speed between A and B in Figure 12.8 is: speed = Dd 20 km 0 km 20 km = = = 20 km/h Dt 8:30 7:30 h 1h If the graph line is horizontal, as it is between B and C, then the slope and the speed are zero: speed = Dd 20 km 20 km 0 km = = = 0 km/h Dt 9:00 8:30 h 0.5 h You Try It! Problem: In Figure 12.8, calculate the speed of the rider between C and D. If you know the speed of a moving object, you can also calculate the distance it will travel in a given amount of time. To do so, you would use this version of the general speed formula:
Question: steepness of a graph line
slope