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Which of the following are structural features of the trachea?

A. C-shaped cartilage

B. Smooth muscle fibers

C. Cilia

D. All of the above

Answer Explanation:

Therefore, the Correct Answer is A.

More Questions on TEAS 7 Science

  • Q #1: Which of these infectious agents do not have nucleic acid?

    A. viroids

    B. viruses

    C. bacteria

    D. prions

    Answer Explanation

  • Q #2: Which of the following are structural features of the trachea?

    A. C-shaped cartilage

    B. Smooth muscle fibers

    C. Cilia

    D. All of the above

    Answer Explanation

  • Q #3: Which of the following processes causes most of the carbon dioxide from the blood to move into the alveoli?

    A. Diffusion down a concentration gradient

    B. Conversion of carbon monoxide

    C. Passive transport using carrier proteins

    D. Active transport using energy

    Answer Explanation

    Carbon dioxide moves from the blood to the alveoli through the process of diffusion. The blood has a high concentration of carbon dioxide than the alveoli.
    Therefore, carbon dioxide diffuses from blood to alveoli through the cell membrane.

  • Q #4: Base your answer on the graph and on your knowledge of biology. Which is a true statement about the relationship between pH and enzyme action?

    A. All enzymes work best at a neutral pH.

    B. Adding more acid does not affect the rate of activity of an enzyme.

    C. Enzymes function only in a pH range of 4.0 to 5.5.

    D. The activity of an enzyme is affected by pH.

    Answer Explanation

  • Q #5: Which of the following statements best supports the hypothesis that viruses can cause cancer?

    A. Cellular DNA has sequences related to viral sequences

    B. Cancerous and normal cells share genetic sequences

    C. Genes that regulate cell division are found in some viruses

    D. Viruses and cancer cells both replicate rapidly

    Answer Explanation

    Cancer is a condition caused by unregulated division of abnormal cells in parts of the body. For a virus to survive in an organism, it must enter into the host’s cell and take control of the cell’s most activities in order to be able to reproduce and replicate.

    Some of the viruses achieve this by inserting their DNA or RNA to that of the host cell. This has a highly likelihood of affecting the DNA or RNA of a host (living organism) which alters their genes, which may lead to host cells becoming cancerous.

    For this reason, viruses can cause cancer because the genes that regulate cell division in host cell are found in some viruses.

  • Q #6: Which of the following are used to determine a person’s DNA sequence?

    A. Genes

    B. Enzymes

    C. Hormones

    D. Blood types

    Answer Explanation

    A gene is the basic physical and functional unit of heredity and it is the DNA that make up genes. Enzymes are biological catalysts that speed up metabolic and cellular reactions in our bodies. Hormones are responsible for controlling the action of certain cells or organs in our bodies. Blood types are of four types, A, B, AB, and O.

  • Q #7: Which of the following is the atomic number of an atom that has 12 protons and 12 neutrons?

    A. 144

    B. 12

    C. 24

    D. 1

    Answer Explanation

    elements are arranged on the periodic table based on their atomic number. This identity is critical in evaluating the chemical families of elements in chemistry. Atoms are made of protons, neutrons, and electrons. Protons and neutrons are found in the nucleus while electrons are found outside the nucleus of the atom. It is the number of protons of an atom that gives its atomic number. Therefore, an atom with 12 protons has an atomic number of 12.

  • Q #8: A myocardial infarction affects which of the following blood vessels of the heart?

    A. Aorta

    B. Vena cava

    C. Pulmonary

    D. Coronary

    Answer Explanation

    A myocardial infarction refers to heart attack, which result from blockage of blood flowing into the heart.

    Blocking is caused by the deposition of fat or cholesterol that forms plaque on the surface of coronary arteries, which supply blood to the heart.

  • Q #9: The Life Cycle of HIV Which of the following allows the AIDS virus, which contains RNA, to insert viral DNA into the DNA of a host T-cell after the AIDS virus enters the cell?

    A. Receptor proteins located on the surface of the virus

    B. The protein that makes up the capsid of the virus

    C. Reverse transcriptase, an enzyme encoded by the virus

    D. The phospholipids found on the envelope of the virus

    Answer Explanation

    The AIDS virus (HIV virus) is Class VI or Group VI in the Baltimore Classification. Based on the Baltimore Classification, this specifically involves the reverse transcriptase enzyme and it is encoded by the virus.

    This is the enzyme that will produce DNA molecules from the viral RNA. This is the mechanism involved where it will use the reverse transcriptase enzyme to insert viral DNA into the genetic material of the host cell.

  • Q #10: Which of the following best describes veins?

    A. thick walled, small lumens, low pressure, lack valves

    B. thin walled, large lumens, low pressure, have valves

    C. thin walled, small lumens, high pressure, have valves

    D. thick walled, large lumens, high pressure, lack valves

    Answer Explanation