(Q).
Answer the following question given this paragraph: Rotation Rotation can occur within the vertebral column, at a pivot joint, or at a ball-and-socket joint. Rotation of the neck or body is the twisting movement produced by the summation of the small rotational movements available between adjacent vertebrae. At a pivot joint, one bone rotates in relation to another bone. This is a uniaxial joint, and thus rotation is the only motion allowed at a pivot joint. For example, at the atlantoaxial joint, the first cervical (C1) vertebra (atlas) rotates around the dens, the upward projection from the second cervical (C2) vertebra (axis). This allows the head to rotate from side to side as when shaking the head "no. " The proximal radioulnar joint is a pivot joint formed by the head of the radius and its articulation with the ulna. This joint allows for the radius to rotate along its length during pronation and supination movements of the forearm. Rotation can also occur at the ball-and-socket joints of the shoulder and hip. Here, the humerus and femur rotate around their long axis, which moves the anterior surface of the arm or thigh either toward or away from the midline of the body. Movement that brings the anterior surface of the limb toward the midline of the body is called medial (internal) rotation. Conversely, rotation of the limb so that the anterior surface moves away from the midline is lateral (external) rotation (see Figure 9.12f). Be sure to distinguish medial and lateral rotation, which can only occur at the multiaxial shoulder and hip joints, from circumduction, which can occur at either biaxial or multiaxial joints. Q: What is the name of a joint in which one bone rotates in relation to another bone? Choices: - gliding - hinge - ball and socket - pivot joint A:
(A).
pivot joint

(Q).
Answer the following question given this paragraph: All living things need water. For most human uses, water must be fresh. Of all the water on Earth, only 1 percent is fresh, liquid water. Most of the rest of Earth's water is either salt water in the ocean or ice in glaciers and ice caps. Q: Although humans require it, what accounts for just one percent of all water on earth? Choices: - snow - salt water - glaciers - fresh water A:
(A).
fresh water

(Q).
Answer the following question given this paragraph: birth of dizygotic (or fraternal) twins. Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at different times. Much less commonly, a zygote can divide into two separate offspring during early development. This results in the birth of monozygotic (or identical) twins. Although the zygote can split as early as the two-cell stage, splitting occurs most commonly during the early blastocyst stage, with roughly 70100 cells present. These two scenarios are distinct from each other, in that the twin embryos that separated at the two-cell stage will have individual placentas, whereas twin embryos that form from separation at the blastocyst stage will share a placenta and a chorionic cavity. Q: Because dizygotic twins develop from two eggs fertilized by two sperm, they are no more identical than siblings born at what? Choices: - other times of day - different places - other eras - different times A:
(A).
different times