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Which of the following properties does soap, an emulsifier, have that make it useful for washing dirt off one’s hands with water?

A. Soap’s dual polar and nonpolar nature helps bond oil and water

B. Soap’s acidity causes grime to precipitate into the water

C. Soap’s enzymatic action helps to dissolve grime into small particles

D. Soap’s rough texture physically scours grime off surfaces

Answer Explanation:

The correct answer is a. Soap’s dual polar and nonpolar nature helps bond oil and water. Soap is an emulsifier, which means that it has both polar and nonpolar regions. The polar regions of soap molecules are atracted to water, while the nonpolar regions are atracted to oil and grease. This allows soap to bond with both water and oil, helping to remove dirt and grime from surfaces.

B. Soap’s acidity does not cause grime to precipitate into the water.

C. Soap does not have enzymatic action that helps to dissolve grime into small particles.

D. Soap’s texture does not physically scour grime off surfaces.

Therefore, the Correct Answer is A.

More Questions on TEAS 7 Science

  • Q #1: Which of the following layers of skin lack blood vessels?

    A. Papillary

    B. Epidermis

    C. Reticular

    D. Hypodermis

    Answer Explanation

    The layer of skin that lacks blood vessels is the epidermis. The epidermis is the thin outer layer of the skin and does not have any blood vessels within it. It is composed of keratinized, stratified squamous epithelium and is made of four or five layers of epithelial cells, depending on its location in the body.

    The other options are not correct because they do contain blood vessels. The papillary layer is part of the dermis, which contains blood vessels. The reticular layer is also part of the dermis and contains blood vessels . The hypodermis is a layer below the dermis and also contains blood vessels.

  • Q #2: An individual suffers severe blunt trauma to the thoracic cavity. Which of the following organs are at greatest risk from this injury?

    A. Heart and lungs

    B. Brain and spinal cord

    C. Liver and stomach

    D. Large and small intestines

    Answer Explanation

    The correct answer is a. Heart and lungs. The thoracic cavity contains the heart and lungs, which are at greatest risk from severe blunt trauma to this area.

    a.The brain and spinal cord are not located in the thoracic cavity and are therefore not at greatest risk from blunt trauma to this area.

    c.The liver and stomach are located in the abdominal cavity, which is below the thoracic cavity. While these organs may be affected by severe blunt trauma to the thoracic cavity, they are not at greatest risk.

    d.The large and small intestines are also located in the abdominal cavity and are not at greatest risk from blunt trauma to the thoracic cavity.

     

  • Q #3: Emphysema caused by damage to alveoli from toxins and pollutants is likely to result in the body having difficulty performing which of the following actions?

    A. Releasing histamine and acetylcholine

    B. Exchanging oxygen and carbon dioxide

    C. Absorbing food

    D. Producing enzymes

    Answer Explanation

    Emphysema is a lung condition that is caused by damage to the alveoli, the tiny air sacs in the lungs where gas exchange occurs. When the alveoli are damaged, the body has difficulty exchanging oxygen and carbon dioxide. This can lead to shortness of breath and other respiratory problems. The other options are not directly related to the function of the alveoli or the effects of emphysema.

  • Q #4: A researcher wants to gather data on the average wing strength of all birds found in the American Northwest. The researcher only has one small net, so all large birds were excluded from the study. The researcher's results were different than expected, but he believes his data include enough birds to estimate the strength of all birds. For which of the following reasons should this data be rejected?

    A. Data contradict the control group

    B. Data were different than expected

    C. Data are biased by the methodology

    D. Data cannot be displayed graphically

    Answer Explanation

    The correct answer is c. Data are biased by the methodology. The researcher's data should be rejected because they are biased by the methodology used to gather them. By only using a small net, the researcher excluded all large birds from the study. This means that the data do not accurately represent the average wing strength of all birds found in the American Northwest.

    A. The data contradicting the control group is not a reason to reject the data in this case.

    B. The data being different than expected is not a reason to reject the data in this case.

    D. The data not being able to be displayed graphically is not a reason to reject the data in this case.

  • Q #5: Parasitic worm infestation is hypothesized to be damaging to the host. However, scientists have recently discovered that worm infestation can relieve the effects of certain autoimmune disorders. In which of the following ways should the hypothesis be modified, given the new findings?

    A. Worm infestation prevents the body from immune malfunction.

    B. Worm infestation reduces the severity of certain autoimmune disorders.

    C. Lack of worm infestations is the cause of some autoimmune disorders.

    D. Worm infestations exacerbate the body's immune reaction.

    Answer Explanation

    Given the new findings that worm infestation can relieve the effects of certain autoimmune disorders, the hypothesis should be modified to state that worm infestation reduces the severity of certain autoimmune disorders.

    This option best reflects the new information and suggests a potential benefit of worm infestation in relation to autoimmune disorders. The other options do not accurately reflect the new findings and do not provide a clear modification to the hypothesis.

  • Q #6: Punnet Square An organism with an unknown genotype is crossed with another organism that shows the recessive trait (aa). The Punnet square below shows the results. Which of the following is the unknown genotype?     Unknown Unkonwn a Aa aa a Aa aa

    A. a

    B. Aa

    C. aa

    D. AA

    Answer Explanation

    The unknown genotype is Aa. This can be inferred from the Punnet square, which shows that half of the offspring are Aa and half are aa. This indicates that the unknown parent must have one dominant allele (A) and one recessive allele (a), making its genotype Aa.

    The other options are not correct because they do not match the results shown in the Punnet square. If the unknown genotype was aa or AA, all of the offspring would have the same genotype as their parent. If the unknown genotype was a, it would not be a valid genotype as it only has one allele.

  • Q #7: Which of the following structures is an exocrine gland?

    A. Pineal gland

    B. Parathyroid gland

    C. Parotid gland

    D. Pituitary gland

    Answer Explanation

    The parotid gland is an exocrine gland that secretes saliva into the mouth. Exocrine glands secrete their products into ducts that carry the secretions to the body's surface or into body cavities. The other options are endocrine glands, which secrete hormones directly into the bloodstream. The pineal gland secretes melatonin, the parathyroid glands secrete parathyroid hormone, and the pituitary gland secretes several hormones that regulate various bodily functions.

  • Q #8: Which of the following processes causes most of the carbon dioxide from the blood to move into the alveoli?

    A. Passive transport using carrier proteins

    B. Active transport using energy

    C. Conversion to carbon monoxide

    D. Diffusion down a concentration gradient

    Answer Explanation

    Most of the carbon dioxide from the blood moves into the alveoli by diffusion down a concentration gradient ¹. Carbon dioxide is always carried in the blood and is released into alveolar air during expiration ¹. Respiratory gases move from higher concentration to lower concentration ¹. In alveolar air, when carbon dioxide is less than in blood, carbon dioxide is released ¹.

    The other options are incorrect because they do not accurately describe the process by which most of the carbon dioxide from the blood moves into the alveoli. Passive transport using carrier proteins, active transport using energy, and conversion to carbon monoxide is not the processes responsible for moving most of the carbon dioxide from the blood into the alveoli.

  • Q #9: Both digestion and absorption happen in which of the following parts of the digestive system?

    A. Gallbladder

    B. Esophagus

    C. Stomach

    D. Small intestine

    Answer Explanation

    Both digestion and absorption happen in the small intestine ¹. Digestion is the process by which food is broken down into small molecules that the body can absorb and use for energy, growth, and repair ¹. The final products of digestion are absorbed from the digestive tract, primarily in the small intestine ¹.

    The other options are not correct because they do not accurately describe where both digestion and absorption happen in the digestive system. The gallbladder stores bile produced by the liver, but does not play a direct role in digestion or absorption. The esophagus transports food from the mouth to the stomach, but does not play a direct role in digestion or absorption. The stomach plays a role in digestion by churning food and mixing it with gastric juices, but most absorption occurs in the small intestine.

  • Q #10: Genetic information describing the characteristics of an organism is found in which of the following?

    A. Nuclei

    B. Membranes

    C. Cilia

    D. Ribosomes

    Answer Explanation

    The correct answer is a. Nuclei. Genetic information describing the characteristics of an organism is found in the nuclei of its cells. The nucleus contains the organism's DNA, which carries the genetic information that determines its traits.

    b. Membranes are structures that surround and enclose cells and organelles, but they do not contain genetic information.

    c. Cilia are hair-like structures that protrude from the surface of some cells and are involved in movement, but they do not contain genetic information.

    d. Ribosomes are organelles that are involved in protein synthesis, but they do not contain genetic information.