Answer the following question given this paragraph: Objects such as ships may float in a fluid like water because of buoyant force. This is an upward force that a fluid exerts on any object that is placed in it. Archimedes discovered that the buoyant force acting on an object equals the weight of the fluid displaced by the object. This is known as Archimedes' law (or Archimedes' principle). For an entertaining video presentation of Archimedes' law, go to this URL:. Q: What is the upward force exerted by fluids when any object, such as a boat, is placed in it? Choices: - human force - atomic force - impetuous force - bouyant force A:
bouyant force
(Question)
Answer the following question given this paragraph: Changes to the nucleus of an atom require tremendous amounts of energy, so protons are not easily gained or lost by atoms. Electrons, on the other hand, are held fairly loosely and can often be removed quite easily. When an object loses some electrons, the remaining object is now positively charged because it has an excess of protons. The electrons may either remain free or may attach to another object. In that case, the extra electrons cause that object to become negatively charged. Atoms that have lost electrons and become positively charged are called positive ions, and atoms that have gained electrons and become negatively charged are called negative ions . Q: Atoms that have gained electrons and become negatively charged are called what? Choices: - negative atoms - cations - anions - negative ions A:
(Answer)
negative ions
Ques: Answer the following question given this paragraph: The hypothalamus is actually part of the brain (see Figure below ), but it also secretes hormones . Some of its hormones "tell" the pituitary gland either to secrete or to stop secreting its hormones. In this way, the hypothalamus provides a link between the nervous and endocrine systems. The hypothalamus also produces hormones that directly regulate body processes. These hormones travel to the pituitary gland, which stores them until they are needed. The hormones include antidiuretic hormone and oxytocin. Q: Which part of the brain secretes hormones that tell the pituitary gland either to secrete or to stop secreting its hormones? Choices: - cerebrum - hippocampus - thalamus - hypothalamus A:
Ans: hypothalamus
(Q).
Answer the following question given this paragraph: There are several different ways to quantitatively describe the concentration of a solution. For example, molarity was introduced in as a useful way to describe solution concentrations for reactions that are carried out in solution. Mole fractions, introduced in , are used not only to describe gas concentrations but also to determine the vapor pressures of mixtures of similar liquids. Example 4 reviews the methods for calculating the molarity and mole fraction of a solution when the masses of its components are known. Q: What is used to describe gas concentrations of a solution? Choices: - fixation fractions - mesh fractions - atom fractions - mole fractions A:
(A).
mole fractions
Ques:Answer the following question given this paragraph: Electrons in the outermost energy level of an atom are called valence electrons. They determine many of the properties of an atom, including how reactive it is. Q: What do you call the electrons in the outermost energy level of an atom? Choices: - Inner electrons - shell electrons - Proper electrons - valence electrons A:

Ans:valence electrons
Answer the following question given this paragraph: Food Energy and ATP Animals need food to obtain energy and maintain homeostasis. Homeostasis is the ability of a system to maintain a stable internal environment even in the face of external changes to the environment. For example, the normal body temperature of humans is 37C (98.6F). Humans maintain this temperature even when the external temperature is hot or cold. It takes energy to maintain this body temperature, and animals obtain this energy from food. The primary source of energy for animals is carbohydrates, mainly glucose. Glucose is called the body's fuel. The digestible carbohydrates in an animal's diet are converted to glucose molecules through a series of catabolic chemical reactions. Adenosine triphosphate, or ATP, is the primary energy currency in cells; ATP stores energy in phosphate ester bonds. ATP releases energy when the phosphodiester bonds are broken and ATP is converted to ADP and a phosphate group. ATP is produced by the oxidative reactions in the cytoplasm and mitochondrion of the cell, where carbohydrates, proteins, and fats undergo a series of metabolic reactions collectively called cellular respiration. For example, glycolysis is a series of reactions in which glucose is converted to pyruvic acid and some of its chemical potential energy is transferred to NADH and ATP. ATP is required for all cellular functions. It is used to build the organic molecules that are required for cells and tissues; it provides energy for muscle contraction and for the transmission of electrical signals in the nervous system. When the amount of ATP is available in excess of the body's requirements, the liver uses the excess ATP and excess glucose to produce molecules called glycogen. Glycogen is a polymeric form of glucose and is stored in the liver and skeletal muscle cells. When blood sugar drops, the liver releases glucose from stores of glycogen. Skeletal muscle converts glycogen to glucose during intense exercise. The process of converting glucose and excess ATP to glycogen and the storage of... Q: What is the term for a system maintaining a stable internal environment in a changeable external environment? Choices: - Pregnant - fetus - hypothesis - homeostasis A:
homeostasis