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Metabolism of proteins Which of the following substances is excreted by sweat glands in response to the breakdown of proteins and the formation of ammonia?

A. Sebum

B. Urea

C. Lysozymes

D. Water

Answer Explanation:

Proteins are nitrogen-based compounds, which when broken down release ammonia. Ammonia is a toxic substance to the body, and sebaceous glands coverts it to urea.

Therefore, the Correct Answer is B.

More Questions on TEAS 7 Science

  • Q #1: Punnett square In a certain plant, red flowers are dominant over white flowers. A plant heterozygous for red flowers and a plant with white flowers are crossed. Which of the following is the expected proportion of phenotypes in the next generation?

    A. 4 red, 0 white

    B. 2 red, 2 white

    C. 1 red, 3 white

    D. 3 red, 1 white

    Answer Explanation

    We use the Punnet square to find the population of the resulting offspring from the crossing of a plant heterozygous for red flowers with a plant with white flowers.

    Let R be the dominant allele for red while r is the recessive allele color for red. Therefore, the phenotype for parent 1 which is heterozygous for red flower will be Rr and the second parent with white flowers will be rr.

    We cross the two phenotypes in a Punnet square as follows

     

    r

    r

    R

    Rr

    Rr

    r

    rr

    rr

     

    Thus, there are 2 heterozygous offspring with red flowers and 2 offspring with white flowers.

  • Q #2: 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 #3: 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 #4: Gel electrophoresis To separate genomic DNA fragments by size, which of these laboratory methods is most useful?

    A. Filtration

    B. Titration

    C. Electrophoresis

    D. Spectrophotometry

    Answer Explanation

    Electrophoresis is a lab method that is commonly used to separate charge molecules based on their size. Some of the charged molecules include DNA, RNA, and proteins.

  • Q #5: Which of these organs is not considered an accessory digestive structure?

    A. mouth

    B. salivary glands

    C. pancreas

    D. liver

    Answer Explanation

    Accessory organs of the digestive system comprise of organs that empty secretions into the alimentary canal. These organs include salivary glands, liver, gallbladder and pancreas. The mount if path of the alimentary canal.

  • Q #6: Lithium has an atomic number of 3 and a mass number of 7. Which of the following is the number of neutrons in a lithium atom?

    A. 4

    B. 7

    C. 12

    D. 3

    Answer Explanation

    The atom is identified by the atomic number in the periodic table. The atomic number is equal to the number of protons and mass number is the sum of the number of protons and neutrons in the nucleus of an atom. Thus, to find how many neutrons are in lithium atom we use the formula below.

    Mass number = number of protons + number of neutrons.

    Letting n be number of neutrons in the lithium atom, we have

    7=3+n

    Rearranging the above equation

    3+n=7

    n=7-3

    n=4

    Thus, lithium atom has 4 neutrons.

  • Q #7: Which of the following vessels carries oxygenated blood?

    A. Inferior vena cava

    B. Pulmonary vein

    C. Pulmonary artery

    D. Superior vena cava

    Answer Explanation

    Pulmonary vein carries oxygenated blood from the lungs to the heart. Pulmonary artery carries deoxygenated blood from the heart to the lungs.
    Superior and inferior vena cava bring in deoxygenated blood from all other parts of the body to the heart.

  • Q #8: 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 #9: Contraction of the external intercostal muscles causes which of the following to occur?

    A. The diaphragm moves downward

    B. The rib cage is compressed

    C. The thoracic cavity volume decreases

    D. The ribs and sternum move upward

    Answer Explanation

    The intercostal muscles are muscles are located along the ribs. The intercostal muscles assist in respiration mechanically. This allows the expansion and contraction of the thorax.
    Contraction of the external intercostal muscle causes the ribs and sternum move upward.

  • Q #10: Practice Question An atom has 14 protons and 20 neutrons. What is its atomic number?

    A. 20

    B. 17

    C. 10

    D. 14

    Answer Explanation