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What type of bond forms between nitrogen and oxygen, and why?

A. Ionic, because electrons are shared

B. Covalent, because electrons are shared

C. Ionic, because electrons are transferred

D. Covalent, because electrons are transferred

Answer Explanation:

Nitrogen and oxygen are both nonmetals, which means they will share electrons in a covalent bond. For example, two oxygen atoms form a double bond, in which two pairs of electrons (four electrons total) are shared. Similarly, two nitrogen atoms form a molecule with a triple bond, in which three pairs of electrons (six electrons total) are shared. 

Therefore, the Correct Answer is B.

More Questions on TEAS 7 Science

  • Q #1: Which choice best describes homeostasis?

    A. A functional system of the body

    B. Blood flow to every cell in the body

    C. A relatively constant environment within the body

    D. Neural pathways that have integrated into the body

    Answer Explanation

    Homeostasis is the existence and maintenance of a relatively constant environment within the body. Each cell of the body is surrounded by a small amount of fluid, and the normal functions of each cell depend on the maintenance of its fluid environment within a narrow range of conditions, including temperature, volume, and chemical content. These conditions are known as variables. For example, body temperature is a variable that can increase in a hot environment or decrease in a cold environment.

    There are two types of feedback mechanisms in the human body: negative and positive.

    • Negative Feedback: Most systems of the body are regulated by negative feedback mechanisms, which maintain homeostasis. Negative means that any deviation from the set point is made smaller or is resisted. The maintenance of normal blood pressure is a negative-feedback mechanism. Normal blood pressure is important because it is responsible for moving blood from the heart to tissues.
    • Positive Feedback: Positive-feedback mechanisms are not homeostatic and are rare in healthy individuals. Positive means that when a deviation from a normal value occurs, the response of the system is to make the deviation even greater. Positive feedback therefore usually creates a cycle leading away from homeostasis and, in some cases, results in death. Inadequate delivery of blood to cardiac muscle is an example of positive feedback.

  • Q #2: Which blood group is a universal donor?

    A. A

    B. B

    C. AB

    D. O

    Answer Explanation

    A person can be a universal blood donor or acceptor. A universal blood donor has type O blood, while a universal blood acceptor has type AB blood.

    There are several different types or groups of blood, and the major groups are A, B, AB, and O. Blood group is a way to classify blood according to inherited differences of red blood cell antigens found on the surface of a red blood cell. The type of antibody in blood also identifies a particular blood group. Antibodies are proteins found in the plasma. They function as part of the body’s natural defense to recognize foreign substances and alert the immune system.

    Depending on which antigen is inherited, parental offspring will have one of the four major blood groups. Collectively, the following major blood groups comprise the ABO system:

    • Blood group A: Displays type A antigens on the surface of a red blood cell and contains B antibodies in the plasma.
    • Blood group B: Displays type B antigens on the red blood cell’s surface and contains A antibodies in the plasma.
    • Blood group O: Does not display A or B antigens on the surface of a red blood cell. Both A and B antibodies are in the plasma.
    • Blood group AB: Displays type A and B antigens on the red blood cell’s surface, but neither A nor B antibodies are in the plasma

    In addition to antigens, the Rh factor protein may exist on a red blood cell’s surface. Because this protein can be either present (+) or absent (-), it increases the number of major blood groups from four to eight: A+, A-, B+, B-, O+, O-, AB+, and AB-.

     

  • Q #3: A person is diagnosed as having acidosis, a condition in which the blood pH is below 7.45. What does the doctor most likely conclude?

    A. Too much carbon dioxide is found in the blood.

    B. Highly oxygenated blood circulates through the body

    C. A blockage prevents blood from leaving the pulmonary artery

    D. The nasal cavity has a difficult time clearing particles from the air.

    Answer Explanation

    Acidosis is when the body fluids contain too much acid, or low pH. The kidneys and lungs are unable to keep the body’s pH in balance. Acidosis is the result when there is too much loss of bicarbonate from the blood known as metabolic acidosis, or due to a buildup of carbon dioxide in the blood due to poor lung function, known as respiratory acidosis. It is the opposite of alkalosis, which is a condition in which there is too much base in the body fluids.